Is there any reason nowadays to use a neon indicator lamp instead of an LED?Why have a small neon lamp in power supply input circuitry?Do standard white LEDs produce a full spectrum of light?Why a neon lamp indicator on power strip switch flickers in the dark?Powering neon indicator lamp from batteryHow does a 120VAC neon indicator lamp respond to a leading-edge triac dimmer?
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Is there any reason nowadays to use a neon indicator lamp instead of an LED?
Why have a small neon lamp in power supply input circuitry?Do standard white LEDs produce a full spectrum of light?Why a neon lamp indicator on power strip switch flickers in the dark?Powering neon indicator lamp from batteryHow does a 120VAC neon indicator lamp respond to a leading-edge triac dimmer?
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I have a bunch of old neon indicator lamps recovered from old AC devices and used to indicate power status.
I wonder: is there any reason nowadays to use the neon lamps instead of LEDs? I see they are still widely available.
LEDs are cheaper even after considering the need for a diode in AC applications. They blink half as often in AC applications, but emit much more light per watt.
In what cases are neon indicator lamps still preferred?
indicator neon
edited Sep 18 at 14:48
psmears
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FarOFarO
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show 6 more comments
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I have a bunch of old neon indicator lamps recovered from old AC devices and used to indicate power status.
I wonder: is there any reason nowadays to use the neon lamps instead of LEDs? I see they are still widely available.
LEDs are cheaper even after considering the need for a diode in AC applications. They blink half as often in AC applications, but emit much more light per watt.
In what cases are neon indicator lamps still preferred?
indicator neon
edited Sep 18 at 14:48
psmears
5633 silver badges5 bronze badges
asked Sep 17 at 12:41
FarOFarO
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Electricians screwdrivers.
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– Andy aka
Sep 17 at 12:44
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I've seen them used as voltage regulators, though mostly in very old circuit designs.
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– Hearth
Sep 17 at 13:43
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When the neon lamp does more than just indicate in an old design it is sometimes wise to replace with a neon. For new designs it is rare that a neon is essential though they are robust. They do wear out though if always illuminated.
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– KalleMP
Sep 18 at 8:53
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Luminous efficacy isn't an unambiguous virtue. I have tons of electronic crap that annoys me with its bright LED lights that I don't want to see at night.
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– chrylis -on strike-
Sep 18 at 10:38
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Neon lamps are were also used as voltage limiters, surge arrestors, sawtooth oscillators and coarse voltage references...
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– rackandboneman
Sep 18 at 11:40
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show 6 more comments
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I have a bunch of old neon indicator lamps recovered from old AC devices and used to indicate power status.
I wonder: is there any reason nowadays to use the neon lamps instead of LEDs? I see they are still widely available.
LEDs are cheaper even after considering the need for a diode in AC applications. They blink half as often in AC applications, but emit much more light per watt.
In what cases are neon indicator lamps still preferred?
indicator neon
edited Sep 18 at 14:48
psmears
5633 silver badges5 bronze badges
asked Sep 17 at 12:41
FarOFarO
1,1089 silver badges27 bronze badges
$endgroup$
I have a bunch of old neon indicator lamps recovered from old AC devices and used to indicate power status.
I wonder: is there any reason nowadays to use the neon lamps instead of LEDs? I see they are still widely available.
LEDs are cheaper even after considering the need for a diode in AC applications. They blink half as often in AC applications, but emit much more light per watt.
In what cases are neon indicator lamps still preferred?
indicator neon
indicator neon
edited Sep 18 at 14:48
psmears
5633 silver badges5 bronze badges
asked Sep 17 at 12:41
FarOFarO
1,1089 silver badges27 bronze badges
edited Sep 18 at 14:48
psmears
5633 silver badges5 bronze badges
asked Sep 17 at 12:41
FarOFarO
1,1089 silver badges27 bronze badges
edited Sep 18 at 14:48
psmears
5633 silver badges5 bronze badges
edited Sep 18 at 14:48
psmears
5633 silver badges5 bronze badges
edited Sep 18 at 14:48
psmears
5633 silver badges5 bronze badges
5633 silver badges5 bronze badges
asked Sep 17 at 12:41
FarOFarO
1,1089 silver badges27 bronze badges
asked Sep 17 at 12:41
FarOFarO
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asked Sep 17 at 12:41
FarOFarO
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1,1089 silver badges27 bronze badges
10
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Electricians screwdrivers.
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– Andy aka
Sep 17 at 12:44
1
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I've seen them used as voltage regulators, though mostly in very old circuit designs.
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– Hearth
Sep 17 at 13:43
1
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When the neon lamp does more than just indicate in an old design it is sometimes wise to replace with a neon. For new designs it is rare that a neon is essential though they are robust. They do wear out though if always illuminated.
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– KalleMP
Sep 18 at 8:53
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Luminous efficacy isn't an unambiguous virtue. I have tons of electronic crap that annoys me with its bright LED lights that I don't want to see at night.
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– chrylis -on strike-
Sep 18 at 10:38
7
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Neon lamps are were also used as voltage limiters, surge arrestors, sawtooth oscillators and coarse voltage references...
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– rackandboneman
Sep 18 at 11:40
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show 6 more comments
10
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Electricians screwdrivers.
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– Andy aka
Sep 17 at 12:44
1
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I've seen them used as voltage regulators, though mostly in very old circuit designs.
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– Hearth
Sep 17 at 13:43
1
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When the neon lamp does more than just indicate in an old design it is sometimes wise to replace with a neon. For new designs it is rare that a neon is essential though they are robust. They do wear out though if always illuminated.
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– KalleMP
Sep 18 at 8:53
8
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Luminous efficacy isn't an unambiguous virtue. I have tons of electronic crap that annoys me with its bright LED lights that I don't want to see at night.
$endgroup$
– chrylis -on strike-
Sep 18 at 10:38
7
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Neon lamps are were also used as voltage limiters, surge arrestors, sawtooth oscillators and coarse voltage references...
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– rackandboneman
Sep 18 at 11:40
10
10
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Electricians screwdrivers.
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– Andy aka
Sep 17 at 12:44
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Electricians screwdrivers.
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– Andy aka
Sep 17 at 12:44
1
1
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I've seen them used as voltage regulators, though mostly in very old circuit designs.
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– Hearth
Sep 17 at 13:43
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I've seen them used as voltage regulators, though mostly in very old circuit designs.
$endgroup$
– Hearth
Sep 17 at 13:43
1
1
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When the neon lamp does more than just indicate in an old design it is sometimes wise to replace with a neon. For new designs it is rare that a neon is essential though they are robust. They do wear out though if always illuminated.
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– KalleMP
Sep 18 at 8:53
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When the neon lamp does more than just indicate in an old design it is sometimes wise to replace with a neon. For new designs it is rare that a neon is essential though they are robust. They do wear out though if always illuminated.
$endgroup$
– KalleMP
Sep 18 at 8:53
8
8
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Luminous efficacy isn't an unambiguous virtue. I have tons of electronic crap that annoys me with its bright LED lights that I don't want to see at night.
$endgroup$
– chrylis -on strike-
Sep 18 at 10:38
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Luminous efficacy isn't an unambiguous virtue. I have tons of electronic crap that annoys me with its bright LED lights that I don't want to see at night.
$endgroup$
– chrylis -on strike-
Sep 18 at 10:38
7
7
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Neon lamps are were also used as voltage limiters, surge arrestors, sawtooth oscillators and coarse voltage references...
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– rackandboneman
Sep 18 at 11:40
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Neon lamps are were also used as voltage limiters, surge arrestors, sawtooth oscillators and coarse voltage references...
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– rackandboneman
Sep 18 at 11:40
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show 6 more comments
13 Answers
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Neon bulbs use microamps of current when fed through a dropping resistor directly from the AC line. LEDs need 10× to 100× the current and can't be fed AC directly.
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
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Well a diode and a led cost less than a neon lamp, but indeed I just discovered that the usual red or green LEDs are much less efficient than "high power/, high efficiency" LEDs. Still I'm surprised that luminous efficiency and a diode make them more popular than cheaper diodes+LEDs.
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– FarO
Sep 17 at 13:09
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But the voltage they operate at means that the Wattage may be much higher than LEDs
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– slebetman
Sep 17 at 21:25
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Yes but that just means the stress on "microamps" also don't matter. Its main advantage is that it can feed directly off AC rather than efficiency - the main reason people don't use them these days is that equipment will invariably have a DC power rail anyway to power the CPU (heck, even a switch has a microcontroller these days)
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– slebetman
Sep 17 at 21:44
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@slebetman: The microamps is important, because it means that a modest 1/4 W resistor can produce the necessary voltage drop. An LED requires both a greater voltage drop AND more current, causing much more power to be wasted.
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– Dave Tweed♦
Sep 17 at 21:46
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Also note that that efficiency doesn't just come from exotic or expensive LEDs. I run a bathroom nightlight LED at around 0.5-1 milliamps, and it could be even lower but still usefully bright for illumination when the eyes are darkness acclimated. It would be overkill for an indicator light. It cost more than the red and yellow LEDs from the same shop, but it was still very cheap.
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– piojo
Sep 18 at 6:31
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I think you'll find neons have more resistance to ESD, transient overvoltage, and high temperatures.
answered Sep 17 at 23:52
abbabb
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You can do many interesting things with neon lamp circuits, all of which are curiosities in 2019 (well maybe they're useful if you need EMP resistance, but I suspect we'll have bigger problems if that's a factor). Neons wear out, for one thing. From the above document:
When I were a lad, I designed a monitor system for Linotype machines (yes, that long ago) using a neon bulb oscillator triggering a then-newfangled C106 SCR (in that horrible package with the 0.05" nominal wide leads), to operate a stepper relay with precious metal contacts multiplexing thermocouples.
I don't see any real reason other than to save a few pennies to use neons as indicator lamps. An NE2H runs at around 2mA, which is sufficient to give more brightness from a decent LED (not all packaged indicators use decent LEDs, however). The neons will wear out if they're powered constantly (rated life is 12,000-25,000 hours which is less than 3 years 24/7).
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
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You may have missed the part in the book about millions of hours lifetime if they are intentionally underdriven. They may be underdriven anyway to put an indicator light at a sensible brightness.
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– Harper - Reinstate Monica
Sep 18 at 20:36
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@Harper The packaged indicators such as these have 25,000 hours for all neon lamps. I don't doubt you can get a feeble glow at 1/10 or 1/100 the current, but that's not the design decision that's typically made, and virtually all the neon indicators I own, from the WTCP solder station to the power bars, are flickering or dead. Never had an indicator LED fail in a commercial product.
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– Spehro Pefhany
Sep 18 at 20:53
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Wow, you really did not read your own reference. Page 16. Derating 1/4 is more than sufficient for human lifetimes.
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– Harper - Reinstate Monica
Sep 18 at 21:45
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Spehro, please explain the circuit above! And what was the Linotype thing you created? It was an actual lead-melting line-o'-type ejecting Linotype? Practically a mechanical supercomputer! Wow! Also where have I seen your name around the Internet? Were you on Usenet or something? I remember your name, though to an English speaker it's quite a distinctive one. I'm sure where you come from, it's like being called "John Smith"!
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– Greenaum
Sep 19 at 5:14
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@Greenaum Yes, Spehro Pefhany was on sci.electronics.* at least as far back as the '90s, I think. I remember seeing him on there back then.
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– Fleetie
Sep 19 at 7:07
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Have a look at this video by BigClive, the light effect (scroll towards end of video to see it) would require a significantly more complex circuit and/or obscure components if you would use LEDs and tried to get the same (random) light effect.
This is the circuit that is used:
I admit that this isn't a "killer application" of neon lamps but more a fun project.
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
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Not an EE answer but aesthetics.
LEDs look uglier. Neon lights occupy more bands in the yellow orange spectrum while LEDs only have a few spikes. See this Q&A on spectrum of LED bulbs (hint: they're just blue LEDs with Phosphor coated lens).
Although more than just a simple lamp, The Nixie tube was a a popular display in the 50s which was used in various technical instruments like voltmeters and frequency counters. It's revival is in part due to its unique, vintage look. Plenty of examples of DIY hobbyists making their vintage displays.
Hellbus [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
answered Sep 18 at 3:58
nabulatornabulator
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Red, yellow or orange LEDs aren't blue+phosphor (though a few greens are, like the lime green I've been using)
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– Chris H
Sep 18 at 11:30
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Neons look uglier when they inevitably begin to flicker and fail. ;-)
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– Spehro Pefhany
Sep 18 at 15:42
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@SpehroPefhany ugh, hate that neon flicker sooooo much LOL
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– Doktor J
Sep 18 at 21:01
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They used to (maybe still do) make neon bulbs with UV emission and phosphor inside the glass to turn that into red, green, blue and maybe other colors. The brightness was a bit disappointing, however, IIRC.
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– Spehro Pefhany
Sep 18 at 21:05
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@SpehroPefhany they're still used: My freezer (only a few years old) has a green neon power indicator. I have to turn the light off in the room or cup my hand over it to see whether it's on. The phosphors do age but they're not great even new. I think they're xenon rather than neon inside, due to the shortage of UV from neon
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– Chris H
Sep 19 at 8:38
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If your equipment is mains voltage, no low-voltage DC available, a neon is a lot easier. As Dave Tweed said, for one thing the resistor can be smaller. Neons can also tolerate the odd voltage surge, and other out-of-spec conditions. An LED has a delicate and tiny structure necessary to it's function. A neon is just some gas and 2 bits of copper.
Things like kettles, radiators, etc, that are mains-only, typically use neons. If it's cheap garbage from Ebay / Amazon, they might (ab)use an LED cos it's cheaper and they don't care about reliability. But why do they always choose blue?
answered Sep 18 at 6:13
GreenaumGreenaum
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Red, or green, will make (at least some) people think of a meaning (red for some error, green for ok (in the sense of "something was actually checked and found ok)). Blue doesn't have that problem.
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– Guntram Blohm supports Monica
Sep 18 at 12:22
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Blue is cruise control for cool.
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– Harper - Reinstate Monica
Sep 18 at 20:13
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Blue is cruise control for insomnia and headaches from chromatic aberration.
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– R..
Sep 19 at 0:26
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I think what it is, is blue LEDs were hideously expensive, 20 years ago, til that Japanese bloke discovered a way of making them cheaply. And got a Nobel Prize for it. Even when his process was implemented, they were expensive for a while. So blue LED = flashy! quality! much chrominance! Then the Chinese forgot this, and carried on using them slavishly anyway. Now it's a sign of cheap crap where the designers aren't fully aware of what they're doing. Like those UK plugs they make, with insulation sleeves on the earth pin.
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– Greenaum
Sep 19 at 4:50
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Incidentally, you can get cheap cigarette lighters with a LED torch in the base. Just an LED and a few tiny batteries, with a springy metal contact for the switch. Usually they're white. But some come with a blue LED, even though blue is the colour the human eye can see least. Green, or better, yellow, would be a better choice if you can't have white. But they use blue ones. A blue torch. What's the point? I suppose it's because they use the same higher voltage as white so can use the same battery arrangement. Even though you can't actually use them to see with. Oh, China!
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– Greenaum
Sep 19 at 4:54
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The need for neons can be related to the industry. For example, equipment that wears out in nuclear facilities must typically be replaced with identical gear, because the cost of qualifying new equipment to operate in the system is so great that it makes no sense to use anything but the old design. If the old design had neons, the replacement typically will too.
The need for neons can also be cosmetic. I build nixie tube clocks for friends and use neons for the colon separating hours and minutes. The color closely matches the color from the nixie filaments, and LEDs just wouldn't look as good.
They also have very low current draw and so are sometimes used as indicators in older designs in emergency power or ride-through applications.
answered Sep 18 at 14:09
schadjoschadjo
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less relevant to your answer itself, but relevant to your anecdote: there are red-orange LEDs out there that very closely match the color of neon/nixie tubes; since neons have spectral peaks around 600nm, 625nm, and 650nm, try looking specifically for an LED with a wavelength of 600-650nm; places like Mouser let you filter by wavelength(s).
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– Doktor J
Sep 18 at 21:13
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That's helpful but I bet they don't have the same flicker! Neons just have an indefinable unique quality. Nothing else is quite the same. And they're nice, people like them. Maybe it's just nostalgia. Actually on a nixie clock it probably is!
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– Greenaum
Sep 19 at 4:56
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@Doktor Thanks for the heads-up.
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– schadjo
Sep 19 at 12:15
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At that Mouser link, there are some red/yellow bi-color LEDs that might better emulate the spectral emission of neon lamps. Putting the LEDs on half-rectified DC, perhaps with a small and not-wholly-adequate smoothing capacitor, could emulate the flicker too. Using $V_ripple = fracI_loadmathitf times C$ if we accept ~1V ripple and our input frequency is 60Hz, and the LEDs use 20mA, $1V = frac0.02A60Hz times C$, $1 times 60 = frac0.02C$, $60 times C = 0.02$, $C = frac0.0260 = 0.0003F$ or 300uF; so a 200-300uF cap would give you some good soft flicker.
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– Doktor J
Sep 24 at 18:22
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Have you actually tried building mains neon vs LED indicators? I bet you haven't.
Here, try a project. Sometimes, a leg of split-phase or 3-phase AC power will drop out at the poletop. Either neutral gets lost, causing L1 to rise and L2 drop, or a leg is lost, causing L1 to be backfed through 240V appliances. Make a very useful gadget that grabs L1, L2 and N, and visually indicates whether L1-N and L2-N are very coarsely the same voltage, and L1-L2 is coarsely 2x the others. The user switches off breakers and watches to see if that affects brightness one to the other. Having 3-4 lights and having the user watch for differences in brightness is fine. Durability a million hours. Needs to be simple and very low parasitic load, energy budget 720mW (3ma). Go.
However, your point is fair that 99% of electronics innovation is done on the low-voltage side of the wall wart. Neon has no place there; it would need an active circuit driving it, and that compares disfavorably with LED.
Neon and LED are different indicator types for different regimes of electricity. When you argue against neon, you're arguing against mains voltage as a supply source. As a big fan of houses having low voltage DC systems so they can happily exist in power-out situations without generators or inverters -- I can't really disagree.
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
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The problem with low-voltage DC systems is the voltage drop. You're using much more current, MUCH more! So the voltage drops get huge, and you'd have to run cable like the stuff on a car battery, if you were gonna start powering all electronics from it. High voltage is much better for distribution. It's like a microcosm of the electrical grid. The longer the distance, the higher the voltage they use. It's the same at home, a scale of dozens of metres means some high voltage, low current, system wins. It's best to convert to DC at point of use. And pretty cheap too.
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– Greenaum
Sep 19 at 5:01
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We don't have split-phase AC in Europe (in fact, I have 3-phase lines directly to my energy meter), so the issue you mention was completely unknown to me.
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– FarO
Sep 19 at 8:23
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@FarO then do it 3-phase, it's just one more phase. European houses also lose phases and neutral. Bonus points for getting the 400V lights to be the same brightness as 230V. And have more energy budget; 2000mw. Visible indicator (differential brightness is fine) for a lost phase or neutral, given that 3-phase appliances will backfeed the dead phase.
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– Harper - Reinstate Monica
Sep 19 at 16:04
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@Greenaum yes, you have to be selective about what you're powering, but lighting and electroncs loads are no problem. For others it is a matter of competent design. HVAC: passive solar design, water heater: gas or solar, etc. LVDC as a unit replacement for buffoonishly designed all-electric homes won't work, obviously.
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– Harper - Reinstate Monica
Sep 19 at 16:18
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Most regular LEDs have about 2 Vdc drop in forward mode and need about 1 mA to light up. although 10 mA is recommended with standard LEDs.
In addition, they can only withstand about 2 Vdc in reverse mode, which means that they need a rectifier diode in series to protect them when the ac voltage changes polarity.
In this configuration, the LED lights up only half of the time, which may reduce its brightness; this could be good or bad depending on the application.
Neon lamps use a 100 K to 250 K, 1/4 W resistor (see http://www.farnell.com/datasheets/57560.pdf).
Neon lamps are not that bright and in certain applications may not stand out when lit, especially in highly lit areas.
With time, neon lamps develop flickering and electrode polarization (only one of the electrodes glows).
Neon lamps are available in various base sizes (see https://www.bulbtown.com/neon_lamps_and_light_bulbs_s/909.htm). Some even come with an internal resistor sized for a specific operating voltage.
answered Sep 18 at 13:37
OscarOscar
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The current requirements of a Neon are low enough that they can generally be driven directly from the mains with a simple and cheap series resistor.
If you try to drive a LED in a similar way you have at least two problems.
- The reverse breakdown voltage is nowhere near high enough to withstand mains voltages, so you end up having to add another diode (potentially another LED) in inverse-parallel.
- Substantially more current is needed, say 10ma or so which is enough to make a resistive dropper consume unconfortbally large amounts of power. You can solve this by using a a capacitive dropper instead but capacitive droppers have their own issues which require extra components to mitigate.
So neons tend to win out in "pure mains" applications, things like indicators on sockets, plugs, power strips, wall switches, surge protectors, heaters with simple electromechanical thermostats and so-on.
If a device is intelligent enough to have a microcontroller on it then LEDs generally win out.
answered Sep 18 at 13:58
Peter GreenPeter Green
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As a point of clarification, a device "intelligent enough to have a microcontroller on it" already necessarily has a low-voltage DC power rail somewhere, making it trivial to power a LED (even if the µc uses something weird like +15VDC, dropping that with a resistor is trivial)
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– Doktor J
Sep 18 at 21:15
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– Greenaum
Sep 19 at 5:07
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Several answers have already discussed the technical reasons, but they don't discuss the applications where those reasons would apply.
A lot of times, you'll see Neon indicators in industrial-grade machinery, for three reasons, two already mentioned:
- Cheaper / easier to drive directly from main voltage (this is important as main voltage rises, like 480V 3-phase systems);
- When under-driven, lifetime is extended substantially;
Simpler installation and circuitry (you can run neons directly off 480V / 277V AC with proper resistors);
As a result, industrial applications using these higher-voltages (note that ANSI still considers 480V a "low-voltage") can save power and cost with appropriately sized neon's. (Sure, it's minimal savings, but typically you need a reason to change something, not keep it the same.)
There are some other curious aspects of industrial systems that generally hold true as well:
- A lot of the logic is 24V DC or 24V AC using relays instead of transistors, easy to drop neons right in;
- The logic often activates raw 480V AC (or 277V AC) equipment -- again, easy to drop a neon in;
- Safety is always a critical issue, because these are often large, dangerous pieces of equipment, so if the bulb dies there should be a possible backup -- once again trivial with neons;
- Industrial equipment is generally expected to take a less-skilled person to service it than smaller electronics (like computers, etc.) -- neons have very common hot-swap plugs on them (LED's are often soldered);
- Industrial equipment may not even have a DC line! -- this means you have to rectify the AC for every LED;
When these aspects are considered, it should make it easier to see why a good chunk of (especially older) industrial-grade equipment would prefer neons to LED's. Especially when considering that if a neon "dies", it's often just extremely dim (vs. completely off as an LED typically is) so it still has minimal functionality.
As an example and anecdote, when I was building the glass manufacturing machines, one feature our machines had was that when plugged in, there was an indicator system that told you if the 480V outlet you plugged into was wired properly. It was extremely cheap to build with Neon's (a few lights and resistors), but would have been slightly more costly (and complex) to build with LED's. (Sure, considering the cost of the machine it was barely noticeable so who cares, but we had no reason to use LED's there and this system has been used by the company for decades, so why spend extra time and money designing a new one?)
Source: I used to maintain and build industrial machinery for a plastic injection molding facility, and a glass machine manufacturing facility.
answered Sep 18 at 21:54
410_Gone410_Gone
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I remember using neon indicator lights as crude, inaccurate, but simple voltage references.
The reality is that in today's electronics there are not the voltages present for neon operation. And there are for LEDs.
answered Sep 18 at 13:26
mongomongo
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I agree with you for today's consumer electronics. Industrial electronics often have to sense and/or be powered by a wide range of standard voltages, so voltages that will light up neons in these applications are more accessible.
$endgroup$
– schadjo
Sep 18 at 14:15
$begingroup$
A mobile phone, maybe, yes. But in the home there's always mains voltage. Actually I'd quite like a phone with neon indicators on it. You could do it with a boost convertor. I wonder if we could troll Apple into adding them to Iphones? Hipsters love all that retro shit. I mean, so do I, but for better, deeper reasons! And I started it before they did!
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– Greenaum
Sep 19 at 5:05
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This is a very niche use, but some neon lamps can be used as logic elements due to the voltage difference in the striking vs maintaining voltages.
You can read about somebody using this, rather than a microcontroller, to control a clock:
- http://www.pa3fwm.nl/projects/neonclock/
- https://hackaday.com/2014/09/29/a-nixie-clock-with-neon-bulb-logic/
answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
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13 Answers
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$begingroup$
Neon bulbs use microamps of current when fed through a dropping resistor directly from the AC line. LEDs need 10× to 100× the current and can't be fed AC directly.
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
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Well a diode and a led cost less than a neon lamp, but indeed I just discovered that the usual red or green LEDs are much less efficient than "high power/, high efficiency" LEDs. Still I'm surprised that luminous efficiency and a diode make them more popular than cheaper diodes+LEDs.
$endgroup$
– FarO
Sep 17 at 13:09
$begingroup$
But the voltage they operate at means that the Wattage may be much higher than LEDs
$endgroup$
– slebetman
Sep 17 at 21:25
6
$begingroup$
Yes but that just means the stress on "microamps" also don't matter. Its main advantage is that it can feed directly off AC rather than efficiency - the main reason people don't use them these days is that equipment will invariably have a DC power rail anyway to power the CPU (heck, even a switch has a microcontroller these days)
$endgroup$
– slebetman
Sep 17 at 21:44
10
$begingroup$
@slebetman: The microamps is important, because it means that a modest 1/4 W resistor can produce the necessary voltage drop. An LED requires both a greater voltage drop AND more current, causing much more power to be wasted.
$endgroup$
– Dave Tweed♦
Sep 17 at 21:46
1
$begingroup$
Also note that that efficiency doesn't just come from exotic or expensive LEDs. I run a bathroom nightlight LED at around 0.5-1 milliamps, and it could be even lower but still usefully bright for illumination when the eyes are darkness acclimated. It would be overkill for an indicator light. It cost more than the red and yellow LEDs from the same shop, but it was still very cheap.
$endgroup$
– piojo
Sep 18 at 6:31
|
show 4 more comments
$begingroup$
Neon bulbs use microamps of current when fed through a dropping resistor directly from the AC line. LEDs need 10× to 100× the current and can't be fed AC directly.
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
143k11 gold badges186 silver badges322 bronze badges
$endgroup$
$begingroup$
Well a diode and a led cost less than a neon lamp, but indeed I just discovered that the usual red or green LEDs are much less efficient than "high power/, high efficiency" LEDs. Still I'm surprised that luminous efficiency and a diode make them more popular than cheaper diodes+LEDs.
$endgroup$
– FarO
Sep 17 at 13:09
$begingroup$
But the voltage they operate at means that the Wattage may be much higher than LEDs
$endgroup$
– slebetman
Sep 17 at 21:25
6
$begingroup$
Yes but that just means the stress on "microamps" also don't matter. Its main advantage is that it can feed directly off AC rather than efficiency - the main reason people don't use them these days is that equipment will invariably have a DC power rail anyway to power the CPU (heck, even a switch has a microcontroller these days)
$endgroup$
– slebetman
Sep 17 at 21:44
10
$begingroup$
@slebetman: The microamps is important, because it means that a modest 1/4 W resistor can produce the necessary voltage drop. An LED requires both a greater voltage drop AND more current, causing much more power to be wasted.
$endgroup$
– Dave Tweed♦
Sep 17 at 21:46
1
$begingroup$
Also note that that efficiency doesn't just come from exotic or expensive LEDs. I run a bathroom nightlight LED at around 0.5-1 milliamps, and it could be even lower but still usefully bright for illumination when the eyes are darkness acclimated. It would be overkill for an indicator light. It cost more than the red and yellow LEDs from the same shop, but it was still very cheap.
$endgroup$
– piojo
Sep 18 at 6:31
|
show 4 more comments
$begingroup$
Neon bulbs use microamps of current when fed through a dropping resistor directly from the AC line. LEDs need 10× to 100× the current and can't be fed AC directly.
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
143k11 gold badges186 silver badges322 bronze badges
$endgroup$
Neon bulbs use microamps of current when fed through a dropping resistor directly from the AC line. LEDs need 10× to 100× the current and can't be fed AC directly.
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
143k11 gold badges186 silver badges322 bronze badges
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
143k11 gold badges186 silver badges322 bronze badges
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
143k11 gold badges186 silver badges322 bronze badges
answered Sep 17 at 12:45
Dave Tweed♦Dave Tweed
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143k11 gold badges186 silver badges322 bronze badges
$begingroup$
Well a diode and a led cost less than a neon lamp, but indeed I just discovered that the usual red or green LEDs are much less efficient than "high power/, high efficiency" LEDs. Still I'm surprised that luminous efficiency and a diode make them more popular than cheaper diodes+LEDs.
$endgroup$
– FarO
Sep 17 at 13:09
$begingroup$
But the voltage they operate at means that the Wattage may be much higher than LEDs
$endgroup$
– slebetman
Sep 17 at 21:25
6
$begingroup$
Yes but that just means the stress on "microamps" also don't matter. Its main advantage is that it can feed directly off AC rather than efficiency - the main reason people don't use them these days is that equipment will invariably have a DC power rail anyway to power the CPU (heck, even a switch has a microcontroller these days)
$endgroup$
– slebetman
Sep 17 at 21:44
10
$begingroup$
@slebetman: The microamps is important, because it means that a modest 1/4 W resistor can produce the necessary voltage drop. An LED requires both a greater voltage drop AND more current, causing much more power to be wasted.
$endgroup$
– Dave Tweed♦
Sep 17 at 21:46
1
$begingroup$
Also note that that efficiency doesn't just come from exotic or expensive LEDs. I run a bathroom nightlight LED at around 0.5-1 milliamps, and it could be even lower but still usefully bright for illumination when the eyes are darkness acclimated. It would be overkill for an indicator light. It cost more than the red and yellow LEDs from the same shop, but it was still very cheap.
$endgroup$
– piojo
Sep 18 at 6:31
|
show 4 more comments
$begingroup$
Well a diode and a led cost less than a neon lamp, but indeed I just discovered that the usual red or green LEDs are much less efficient than "high power/, high efficiency" LEDs. Still I'm surprised that luminous efficiency and a diode make them more popular than cheaper diodes+LEDs.
$endgroup$
– FarO
Sep 17 at 13:09
$begingroup$
But the voltage they operate at means that the Wattage may be much higher than LEDs
$endgroup$
– slebetman
Sep 17 at 21:25
6
$begingroup$
Yes but that just means the stress on "microamps" also don't matter. Its main advantage is that it can feed directly off AC rather than efficiency - the main reason people don't use them these days is that equipment will invariably have a DC power rail anyway to power the CPU (heck, even a switch has a microcontroller these days)
$endgroup$
– slebetman
Sep 17 at 21:44
10
$begingroup$
@slebetman: The microamps is important, because it means that a modest 1/4 W resistor can produce the necessary voltage drop. An LED requires both a greater voltage drop AND more current, causing much more power to be wasted.
$endgroup$
– Dave Tweed♦
Sep 17 at 21:46
1
$begingroup$
Also note that that efficiency doesn't just come from exotic or expensive LEDs. I run a bathroom nightlight LED at around 0.5-1 milliamps, and it could be even lower but still usefully bright for illumination when the eyes are darkness acclimated. It would be overkill for an indicator light. It cost more than the red and yellow LEDs from the same shop, but it was still very cheap.
$endgroup$
– piojo
Sep 18 at 6:31
$begingroup$
Well a diode and a led cost less than a neon lamp, but indeed I just discovered that the usual red or green LEDs are much less efficient than "high power/, high efficiency" LEDs. Still I'm surprised that luminous efficiency and a diode make them more popular than cheaper diodes+LEDs.
$endgroup$
– FarO
Sep 17 at 13:09
$begingroup$
Well a diode and a led cost less than a neon lamp, but indeed I just discovered that the usual red or green LEDs are much less efficient than "high power/, high efficiency" LEDs. Still I'm surprised that luminous efficiency and a diode make them more popular than cheaper diodes+LEDs.
$endgroup$
– FarO
Sep 17 at 13:09
$begingroup$
But the voltage they operate at means that the Wattage may be much higher than LEDs
$endgroup$
– slebetman
Sep 17 at 21:25
$begingroup$
But the voltage they operate at means that the Wattage may be much higher than LEDs
$endgroup$
– slebetman
Sep 17 at 21:25
6
6
$begingroup$
Yes but that just means the stress on "microamps" also don't matter. Its main advantage is that it can feed directly off AC rather than efficiency - the main reason people don't use them these days is that equipment will invariably have a DC power rail anyway to power the CPU (heck, even a switch has a microcontroller these days)
$endgroup$
– slebetman
Sep 17 at 21:44
$begingroup$
Yes but that just means the stress on "microamps" also don't matter. Its main advantage is that it can feed directly off AC rather than efficiency - the main reason people don't use them these days is that equipment will invariably have a DC power rail anyway to power the CPU (heck, even a switch has a microcontroller these days)
$endgroup$
– slebetman
Sep 17 at 21:44
10
10
$begingroup$
@slebetman: The microamps is important, because it means that a modest 1/4 W resistor can produce the necessary voltage drop. An LED requires both a greater voltage drop AND more current, causing much more power to be wasted.
$endgroup$
– Dave Tweed♦
Sep 17 at 21:46
$begingroup$
@slebetman: The microamps is important, because it means that a modest 1/4 W resistor can produce the necessary voltage drop. An LED requires both a greater voltage drop AND more current, causing much more power to be wasted.
$endgroup$
– Dave Tweed♦
Sep 17 at 21:46
1
1
$begingroup$
Also note that that efficiency doesn't just come from exotic or expensive LEDs. I run a bathroom nightlight LED at around 0.5-1 milliamps, and it could be even lower but still usefully bright for illumination when the eyes are darkness acclimated. It would be overkill for an indicator light. It cost more than the red and yellow LEDs from the same shop, but it was still very cheap.
$endgroup$
– piojo
Sep 18 at 6:31
$begingroup$
Also note that that efficiency doesn't just come from exotic or expensive LEDs. I run a bathroom nightlight LED at around 0.5-1 milliamps, and it could be even lower but still usefully bright for illumination when the eyes are darkness acclimated. It would be overkill for an indicator light. It cost more than the red and yellow LEDs from the same shop, but it was still very cheap.
$endgroup$
– piojo
Sep 18 at 6:31
|
show 4 more comments
$begingroup$
I think you'll find neons have more resistance to ESD, transient overvoltage, and high temperatures.
answered Sep 17 at 23:52
abbabb
3155 bronze badges
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I think you'll find neons have more resistance to ESD, transient overvoltage, and high temperatures.
answered Sep 17 at 23:52
abbabb
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I think you'll find neons have more resistance to ESD, transient overvoltage, and high temperatures.
answered Sep 17 at 23:52
abbabb
3155 bronze badges
$endgroup$
I think you'll find neons have more resistance to ESD, transient overvoltage, and high temperatures.
answered Sep 17 at 23:52
abbabb
3155 bronze badges
answered Sep 17 at 23:52
abbabb
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answered Sep 17 at 23:52
abbabb
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answered Sep 17 at 23:52
abbabb
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You can do many interesting things with neon lamp circuits, all of which are curiosities in 2019 (well maybe they're useful if you need EMP resistance, but I suspect we'll have bigger problems if that's a factor). Neons wear out, for one thing. From the above document:
When I were a lad, I designed a monitor system for Linotype machines (yes, that long ago) using a neon bulb oscillator triggering a then-newfangled C106 SCR (in that horrible package with the 0.05" nominal wide leads), to operate a stepper relay with precious metal contacts multiplexing thermocouples.
I don't see any real reason other than to save a few pennies to use neons as indicator lamps. An NE2H runs at around 2mA, which is sufficient to give more brightness from a decent LED (not all packaged indicators use decent LEDs, however). The neons will wear out if they're powered constantly (rated life is 12,000-25,000 hours which is less than 3 years 24/7).
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
228k6 gold badges183 silver badges481 bronze badges
$endgroup$
1
$begingroup$
You may have missed the part in the book about millions of hours lifetime if they are intentionally underdriven. They may be underdriven anyway to put an indicator light at a sensible brightness.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:36
2
$begingroup$
@Harper The packaged indicators such as these have 25,000 hours for all neon lamps. I don't doubt you can get a feeble glow at 1/10 or 1/100 the current, but that's not the design decision that's typically made, and virtually all the neon indicators I own, from the WTCP solder station to the power bars, are flickering or dead. Never had an indicator LED fail in a commercial product.
$endgroup$
– Spehro Pefhany
Sep 18 at 20:53
2
$begingroup$
Wow, you really did not read your own reference. Page 16. Derating 1/4 is more than sufficient for human lifetimes.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 21:45
1
$begingroup$
Spehro, please explain the circuit above! And what was the Linotype thing you created? It was an actual lead-melting line-o'-type ejecting Linotype? Practically a mechanical supercomputer! Wow! Also where have I seen your name around the Internet? Were you on Usenet or something? I remember your name, though to an English speaker it's quite a distinctive one. I'm sure where you come from, it's like being called "John Smith"!
$endgroup$
– Greenaum
Sep 19 at 5:14
2
$begingroup$
@Greenaum Yes, Spehro Pefhany was on sci.electronics.* at least as far back as the '90s, I think. I remember seeing him on there back then.
$endgroup$
– Fleetie
Sep 19 at 7:07
|
show 2 more comments
$begingroup$
You can do many interesting things with neon lamp circuits, all of which are curiosities in 2019 (well maybe they're useful if you need EMP resistance, but I suspect we'll have bigger problems if that's a factor). Neons wear out, for one thing. From the above document:
When I were a lad, I designed a monitor system for Linotype machines (yes, that long ago) using a neon bulb oscillator triggering a then-newfangled C106 SCR (in that horrible package with the 0.05" nominal wide leads), to operate a stepper relay with precious metal contacts multiplexing thermocouples.
I don't see any real reason other than to save a few pennies to use neons as indicator lamps. An NE2H runs at around 2mA, which is sufficient to give more brightness from a decent LED (not all packaged indicators use decent LEDs, however). The neons will wear out if they're powered constantly (rated life is 12,000-25,000 hours which is less than 3 years 24/7).
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
228k6 gold badges183 silver badges481 bronze badges
$endgroup$
1
$begingroup$
You may have missed the part in the book about millions of hours lifetime if they are intentionally underdriven. They may be underdriven anyway to put an indicator light at a sensible brightness.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:36
2
$begingroup$
@Harper The packaged indicators such as these have 25,000 hours for all neon lamps. I don't doubt you can get a feeble glow at 1/10 or 1/100 the current, but that's not the design decision that's typically made, and virtually all the neon indicators I own, from the WTCP solder station to the power bars, are flickering or dead. Never had an indicator LED fail in a commercial product.
$endgroup$
– Spehro Pefhany
Sep 18 at 20:53
2
$begingroup$
Wow, you really did not read your own reference. Page 16. Derating 1/4 is more than sufficient for human lifetimes.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 21:45
1
$begingroup$
Spehro, please explain the circuit above! And what was the Linotype thing you created? It was an actual lead-melting line-o'-type ejecting Linotype? Practically a mechanical supercomputer! Wow! Also where have I seen your name around the Internet? Were you on Usenet or something? I remember your name, though to an English speaker it's quite a distinctive one. I'm sure where you come from, it's like being called "John Smith"!
$endgroup$
– Greenaum
Sep 19 at 5:14
2
$begingroup$
@Greenaum Yes, Spehro Pefhany was on sci.electronics.* at least as far back as the '90s, I think. I remember seeing him on there back then.
$endgroup$
– Fleetie
Sep 19 at 7:07
|
show 2 more comments
$begingroup$
You can do many interesting things with neon lamp circuits, all of which are curiosities in 2019 (well maybe they're useful if you need EMP resistance, but I suspect we'll have bigger problems if that's a factor). Neons wear out, for one thing. From the above document:
When I were a lad, I designed a monitor system for Linotype machines (yes, that long ago) using a neon bulb oscillator triggering a then-newfangled C106 SCR (in that horrible package with the 0.05" nominal wide leads), to operate a stepper relay with precious metal contacts multiplexing thermocouples.
I don't see any real reason other than to save a few pennies to use neons as indicator lamps. An NE2H runs at around 2mA, which is sufficient to give more brightness from a decent LED (not all packaged indicators use decent LEDs, however). The neons will wear out if they're powered constantly (rated life is 12,000-25,000 hours which is less than 3 years 24/7).
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
228k6 gold badges183 silver badges481 bronze badges
$endgroup$
You can do many interesting things with neon lamp circuits, all of which are curiosities in 2019 (well maybe they're useful if you need EMP resistance, but I suspect we'll have bigger problems if that's a factor). Neons wear out, for one thing. From the above document:
When I were a lad, I designed a monitor system for Linotype machines (yes, that long ago) using a neon bulb oscillator triggering a then-newfangled C106 SCR (in that horrible package with the 0.05" nominal wide leads), to operate a stepper relay with precious metal contacts multiplexing thermocouples.
I don't see any real reason other than to save a few pennies to use neons as indicator lamps. An NE2H runs at around 2mA, which is sufficient to give more brightness from a decent LED (not all packaged indicators use decent LEDs, however). The neons will wear out if they're powered constantly (rated life is 12,000-25,000 hours which is less than 3 years 24/7).
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
228k6 gold badges183 silver badges481 bronze badges
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
228k6 gold badges183 silver badges481 bronze badges
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
228k6 gold badges183 silver badges481 bronze badges
answered Sep 18 at 14:23
Spehro PefhanySpehro Pefhany
228k6 gold badges183 silver badges481 bronze badges
228k6 gold badges183 silver badges481 bronze badges
1
$begingroup$
You may have missed the part in the book about millions of hours lifetime if they are intentionally underdriven. They may be underdriven anyway to put an indicator light at a sensible brightness.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:36
2
$begingroup$
@Harper The packaged indicators such as these have 25,000 hours for all neon lamps. I don't doubt you can get a feeble glow at 1/10 or 1/100 the current, but that's not the design decision that's typically made, and virtually all the neon indicators I own, from the WTCP solder station to the power bars, are flickering or dead. Never had an indicator LED fail in a commercial product.
$endgroup$
– Spehro Pefhany
Sep 18 at 20:53
2
$begingroup$
Wow, you really did not read your own reference. Page 16. Derating 1/4 is more than sufficient for human lifetimes.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 21:45
1
$begingroup$
Spehro, please explain the circuit above! And what was the Linotype thing you created? It was an actual lead-melting line-o'-type ejecting Linotype? Practically a mechanical supercomputer! Wow! Also where have I seen your name around the Internet? Were you on Usenet or something? I remember your name, though to an English speaker it's quite a distinctive one. I'm sure where you come from, it's like being called "John Smith"!
$endgroup$
– Greenaum
Sep 19 at 5:14
2
$begingroup$
@Greenaum Yes, Spehro Pefhany was on sci.electronics.* at least as far back as the '90s, I think. I remember seeing him on there back then.
$endgroup$
– Fleetie
Sep 19 at 7:07
|
show 2 more comments
1
$begingroup$
You may have missed the part in the book about millions of hours lifetime if they are intentionally underdriven. They may be underdriven anyway to put an indicator light at a sensible brightness.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:36
2
$begingroup$
@Harper The packaged indicators such as these have 25,000 hours for all neon lamps. I don't doubt you can get a feeble glow at 1/10 or 1/100 the current, but that's not the design decision that's typically made, and virtually all the neon indicators I own, from the WTCP solder station to the power bars, are flickering or dead. Never had an indicator LED fail in a commercial product.
$endgroup$
– Spehro Pefhany
Sep 18 at 20:53
2
$begingroup$
Wow, you really did not read your own reference. Page 16. Derating 1/4 is more than sufficient for human lifetimes.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 21:45
1
$begingroup$
Spehro, please explain the circuit above! And what was the Linotype thing you created? It was an actual lead-melting line-o'-type ejecting Linotype? Practically a mechanical supercomputer! Wow! Also where have I seen your name around the Internet? Were you on Usenet or something? I remember your name, though to an English speaker it's quite a distinctive one. I'm sure where you come from, it's like being called "John Smith"!
$endgroup$
– Greenaum
Sep 19 at 5:14
2
$begingroup$
@Greenaum Yes, Spehro Pefhany was on sci.electronics.* at least as far back as the '90s, I think. I remember seeing him on there back then.
$endgroup$
– Fleetie
Sep 19 at 7:07
1
1
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You may have missed the part in the book about millions of hours lifetime if they are intentionally underdriven. They may be underdriven anyway to put an indicator light at a sensible brightness.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:36
$begingroup$
You may have missed the part in the book about millions of hours lifetime if they are intentionally underdriven. They may be underdriven anyway to put an indicator light at a sensible brightness.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:36
2
2
$begingroup$
@Harper The packaged indicators such as these have 25,000 hours for all neon lamps. I don't doubt you can get a feeble glow at 1/10 or 1/100 the current, but that's not the design decision that's typically made, and virtually all the neon indicators I own, from the WTCP solder station to the power bars, are flickering or dead. Never had an indicator LED fail in a commercial product.
$endgroup$
– Spehro Pefhany
Sep 18 at 20:53
$begingroup$
@Harper The packaged indicators such as these have 25,000 hours for all neon lamps. I don't doubt you can get a feeble glow at 1/10 or 1/100 the current, but that's not the design decision that's typically made, and virtually all the neon indicators I own, from the WTCP solder station to the power bars, are flickering or dead. Never had an indicator LED fail in a commercial product.
$endgroup$
– Spehro Pefhany
Sep 18 at 20:53
2
2
$begingroup$
Wow, you really did not read your own reference. Page 16. Derating 1/4 is more than sufficient for human lifetimes.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 21:45
$begingroup$
Wow, you really did not read your own reference. Page 16. Derating 1/4 is more than sufficient for human lifetimes.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 21:45
1
1
$begingroup$
Spehro, please explain the circuit above! And what was the Linotype thing you created? It was an actual lead-melting line-o'-type ejecting Linotype? Practically a mechanical supercomputer! Wow! Also where have I seen your name around the Internet? Were you on Usenet or something? I remember your name, though to an English speaker it's quite a distinctive one. I'm sure where you come from, it's like being called "John Smith"!
$endgroup$
– Greenaum
Sep 19 at 5:14
$begingroup$
Spehro, please explain the circuit above! And what was the Linotype thing you created? It was an actual lead-melting line-o'-type ejecting Linotype? Practically a mechanical supercomputer! Wow! Also where have I seen your name around the Internet? Were you on Usenet or something? I remember your name, though to an English speaker it's quite a distinctive one. I'm sure where you come from, it's like being called "John Smith"!
$endgroup$
– Greenaum
Sep 19 at 5:14
2
2
$begingroup$
@Greenaum Yes, Spehro Pefhany was on sci.electronics.* at least as far back as the '90s, I think. I remember seeing him on there back then.
$endgroup$
– Fleetie
Sep 19 at 7:07
$begingroup$
@Greenaum Yes, Spehro Pefhany was on sci.electronics.* at least as far back as the '90s, I think. I remember seeing him on there back then.
$endgroup$
– Fleetie
Sep 19 at 7:07
|
show 2 more comments
$begingroup$
Have a look at this video by BigClive, the light effect (scroll towards end of video to see it) would require a significantly more complex circuit and/or obscure components if you would use LEDs and tried to get the same (random) light effect.
This is the circuit that is used:
I admit that this isn't a "killer application" of neon lamps but more a fun project.
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
61.3k2 gold badges64 silver badges140 bronze badges
$endgroup$
add a comment
|
$begingroup$
Have a look at this video by BigClive, the light effect (scroll towards end of video to see it) would require a significantly more complex circuit and/or obscure components if you would use LEDs and tried to get the same (random) light effect.
This is the circuit that is used:
I admit that this isn't a "killer application" of neon lamps but more a fun project.
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
61.3k2 gold badges64 silver badges140 bronze badges
$endgroup$
add a comment
|
$begingroup$
Have a look at this video by BigClive, the light effect (scroll towards end of video to see it) would require a significantly more complex circuit and/or obscure components if you would use LEDs and tried to get the same (random) light effect.
This is the circuit that is used:
I admit that this isn't a "killer application" of neon lamps but more a fun project.
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
61.3k2 gold badges64 silver badges140 bronze badges
$endgroup$
Have a look at this video by BigClive, the light effect (scroll towards end of video to see it) would require a significantly more complex circuit and/or obscure components if you would use LEDs and tried to get the same (random) light effect.
This is the circuit that is used:
I admit that this isn't a "killer application" of neon lamps but more a fun project.
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
61.3k2 gold badges64 silver badges140 bronze badges
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
61.3k2 gold badges64 silver badges140 bronze badges
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
61.3k2 gold badges64 silver badges140 bronze badges
answered Sep 17 at 12:54
BimpelrekkieBimpelrekkie
61.3k2 gold badges64 silver badges140 bronze badges
61.3k2 gold badges64 silver badges140 bronze badges
add a comment
|
add a comment
|
$begingroup$
Not an EE answer but aesthetics.
LEDs look uglier. Neon lights occupy more bands in the yellow orange spectrum while LEDs only have a few spikes. See this Q&A on spectrum of LED bulbs (hint: they're just blue LEDs with Phosphor coated lens).
Although more than just a simple lamp, The Nixie tube was a a popular display in the 50s which was used in various technical instruments like voltmeters and frequency counters. It's revival is in part due to its unique, vintage look. Plenty of examples of DIY hobbyists making their vintage displays.
Hellbus [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
answered Sep 18 at 3:58
nabulatornabulator
5221 gold badge3 silver badges15 bronze badges
$endgroup$
3
$begingroup$
Red, yellow or orange LEDs aren't blue+phosphor (though a few greens are, like the lime green I've been using)
$endgroup$
– Chris H
Sep 18 at 11:30
11
$begingroup$
Neons look uglier when they inevitably begin to flicker and fail. ;-)
$endgroup$
– Spehro Pefhany
Sep 18 at 15:42
1
$begingroup$
@SpehroPefhany ugh, hate that neon flicker sooooo much LOL
$endgroup$
– Doktor J
Sep 18 at 21:01
$begingroup$
They used to (maybe still do) make neon bulbs with UV emission and phosphor inside the glass to turn that into red, green, blue and maybe other colors. The brightness was a bit disappointing, however, IIRC.
$endgroup$
– Spehro Pefhany
Sep 18 at 21:05
1
$begingroup$
@SpehroPefhany they're still used: My freezer (only a few years old) has a green neon power indicator. I have to turn the light off in the room or cup my hand over it to see whether it's on. The phosphors do age but they're not great even new. I think they're xenon rather than neon inside, due to the shortage of UV from neon
$endgroup$
– Chris H
Sep 19 at 8:38
add a comment
|
$begingroup$
Not an EE answer but aesthetics.
LEDs look uglier. Neon lights occupy more bands in the yellow orange spectrum while LEDs only have a few spikes. See this Q&A on spectrum of LED bulbs (hint: they're just blue LEDs with Phosphor coated lens).
Although more than just a simple lamp, The Nixie tube was a a popular display in the 50s which was used in various technical instruments like voltmeters and frequency counters. It's revival is in part due to its unique, vintage look. Plenty of examples of DIY hobbyists making their vintage displays.
Hellbus [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
answered Sep 18 at 3:58
nabulatornabulator
5221 gold badge3 silver badges15 bronze badges
$endgroup$
3
$begingroup$
Red, yellow or orange LEDs aren't blue+phosphor (though a few greens are, like the lime green I've been using)
$endgroup$
– Chris H
Sep 18 at 11:30
11
$begingroup$
Neons look uglier when they inevitably begin to flicker and fail. ;-)
$endgroup$
– Spehro Pefhany
Sep 18 at 15:42
1
$begingroup$
@SpehroPefhany ugh, hate that neon flicker sooooo much LOL
$endgroup$
– Doktor J
Sep 18 at 21:01
$begingroup$
They used to (maybe still do) make neon bulbs with UV emission and phosphor inside the glass to turn that into red, green, blue and maybe other colors. The brightness was a bit disappointing, however, IIRC.
$endgroup$
– Spehro Pefhany
Sep 18 at 21:05
1
$begingroup$
@SpehroPefhany they're still used: My freezer (only a few years old) has a green neon power indicator. I have to turn the light off in the room or cup my hand over it to see whether it's on. The phosphors do age but they're not great even new. I think they're xenon rather than neon inside, due to the shortage of UV from neon
$endgroup$
– Chris H
Sep 19 at 8:38
add a comment
|
$begingroup$
Not an EE answer but aesthetics.
LEDs look uglier. Neon lights occupy more bands in the yellow orange spectrum while LEDs only have a few spikes. See this Q&A on spectrum of LED bulbs (hint: they're just blue LEDs with Phosphor coated lens).
Although more than just a simple lamp, The Nixie tube was a a popular display in the 50s which was used in various technical instruments like voltmeters and frequency counters. It's revival is in part due to its unique, vintage look. Plenty of examples of DIY hobbyists making their vintage displays.
Hellbus [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
answered Sep 18 at 3:58
nabulatornabulator
5221 gold badge3 silver badges15 bronze badges
$endgroup$
Not an EE answer but aesthetics.
LEDs look uglier. Neon lights occupy more bands in the yellow orange spectrum while LEDs only have a few spikes. See this Q&A on spectrum of LED bulbs (hint: they're just blue LEDs with Phosphor coated lens).
Although more than just a simple lamp, The Nixie tube was a a popular display in the 50s which was used in various technical instruments like voltmeters and frequency counters. It's revival is in part due to its unique, vintage look. Plenty of examples of DIY hobbyists making their vintage displays.
Hellbus [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
answered Sep 18 at 3:58
nabulatornabulator
5221 gold badge3 silver badges15 bronze badges
answered Sep 18 at 3:58
nabulatornabulator
5221 gold badge3 silver badges15 bronze badges
answered Sep 18 at 3:58
nabulatornabulator
5221 gold badge3 silver badges15 bronze badges
answered Sep 18 at 3:58
nabulatornabulator
5221 gold badge3 silver badges15 bronze badges
5221 gold badge3 silver badges15 bronze badges
3
$begingroup$
Red, yellow or orange LEDs aren't blue+phosphor (though a few greens are, like the lime green I've been using)
$endgroup$
– Chris H
Sep 18 at 11:30
11
$begingroup$
Neons look uglier when they inevitably begin to flicker and fail. ;-)
$endgroup$
– Spehro Pefhany
Sep 18 at 15:42
1
$begingroup$
@SpehroPefhany ugh, hate that neon flicker sooooo much LOL
$endgroup$
– Doktor J
Sep 18 at 21:01
$begingroup$
They used to (maybe still do) make neon bulbs with UV emission and phosphor inside the glass to turn that into red, green, blue and maybe other colors. The brightness was a bit disappointing, however, IIRC.
$endgroup$
– Spehro Pefhany
Sep 18 at 21:05
1
$begingroup$
@SpehroPefhany they're still used: My freezer (only a few years old) has a green neon power indicator. I have to turn the light off in the room or cup my hand over it to see whether it's on. The phosphors do age but they're not great even new. I think they're xenon rather than neon inside, due to the shortage of UV from neon
$endgroup$
– Chris H
Sep 19 at 8:38
add a comment
|
3
$begingroup$
Red, yellow or orange LEDs aren't blue+phosphor (though a few greens are, like the lime green I've been using)
$endgroup$
– Chris H
Sep 18 at 11:30
11
$begingroup$
Neons look uglier when they inevitably begin to flicker and fail. ;-)
$endgroup$
– Spehro Pefhany
Sep 18 at 15:42
1
$begingroup$
@SpehroPefhany ugh, hate that neon flicker sooooo much LOL
$endgroup$
– Doktor J
Sep 18 at 21:01
$begingroup$
They used to (maybe still do) make neon bulbs with UV emission and phosphor inside the glass to turn that into red, green, blue and maybe other colors. The brightness was a bit disappointing, however, IIRC.
$endgroup$
– Spehro Pefhany
Sep 18 at 21:05
1
$begingroup$
@SpehroPefhany they're still used: My freezer (only a few years old) has a green neon power indicator. I have to turn the light off in the room or cup my hand over it to see whether it's on. The phosphors do age but they're not great even new. I think they're xenon rather than neon inside, due to the shortage of UV from neon
$endgroup$
– Chris H
Sep 19 at 8:38
3
3
$begingroup$
Red, yellow or orange LEDs aren't blue+phosphor (though a few greens are, like the lime green I've been using)
$endgroup$
– Chris H
Sep 18 at 11:30
$begingroup$
Red, yellow or orange LEDs aren't blue+phosphor (though a few greens are, like the lime green I've been using)
$endgroup$
– Chris H
Sep 18 at 11:30
11
11
$begingroup$
Neons look uglier when they inevitably begin to flicker and fail. ;-)
$endgroup$
– Spehro Pefhany
Sep 18 at 15:42
$begingroup$
Neons look uglier when they inevitably begin to flicker and fail. ;-)
$endgroup$
– Spehro Pefhany
Sep 18 at 15:42
1
1
$begingroup$
@SpehroPefhany ugh, hate that neon flicker sooooo much LOL
$endgroup$
– Doktor J
Sep 18 at 21:01
$begingroup$
@SpehroPefhany ugh, hate that neon flicker sooooo much LOL
$endgroup$
– Doktor J
Sep 18 at 21:01
$begingroup$
They used to (maybe still do) make neon bulbs with UV emission and phosphor inside the glass to turn that into red, green, blue and maybe other colors. The brightness was a bit disappointing, however, IIRC.
$endgroup$
– Spehro Pefhany
Sep 18 at 21:05
$begingroup$
They used to (maybe still do) make neon bulbs with UV emission and phosphor inside the glass to turn that into red, green, blue and maybe other colors. The brightness was a bit disappointing, however, IIRC.
$endgroup$
– Spehro Pefhany
Sep 18 at 21:05
1
1
$begingroup$
@SpehroPefhany they're still used: My freezer (only a few years old) has a green neon power indicator. I have to turn the light off in the room or cup my hand over it to see whether it's on. The phosphors do age but they're not great even new. I think they're xenon rather than neon inside, due to the shortage of UV from neon
$endgroup$
– Chris H
Sep 19 at 8:38
$begingroup$
@SpehroPefhany they're still used: My freezer (only a few years old) has a green neon power indicator. I have to turn the light off in the room or cup my hand over it to see whether it's on. The phosphors do age but they're not great even new. I think they're xenon rather than neon inside, due to the shortage of UV from neon
$endgroup$
– Chris H
Sep 19 at 8:38
add a comment
|
$begingroup$
If your equipment is mains voltage, no low-voltage DC available, a neon is a lot easier. As Dave Tweed said, for one thing the resistor can be smaller. Neons can also tolerate the odd voltage surge, and other out-of-spec conditions. An LED has a delicate and tiny structure necessary to it's function. A neon is just some gas and 2 bits of copper.
Things like kettles, radiators, etc, that are mains-only, typically use neons. If it's cheap garbage from Ebay / Amazon, they might (ab)use an LED cos it's cheaper and they don't care about reliability. But why do they always choose blue?
answered Sep 18 at 6:13
GreenaumGreenaum
2911 silver badge5 bronze badges
$endgroup$
2
$begingroup$
Red, or green, will make (at least some) people think of a meaning (red for some error, green for ok (in the sense of "something was actually checked and found ok)). Blue doesn't have that problem.
$endgroup$
– Guntram Blohm supports Monica
Sep 18 at 12:22
2
$begingroup$
Blue is cruise control for cool.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:13
1
$begingroup$
Blue is cruise control for insomnia and headaches from chromatic aberration.
$endgroup$
– R..
Sep 19 at 0:26
1
$begingroup$
I think what it is, is blue LEDs were hideously expensive, 20 years ago, til that Japanese bloke discovered a way of making them cheaply. And got a Nobel Prize for it. Even when his process was implemented, they were expensive for a while. So blue LED = flashy! quality! much chrominance! Then the Chinese forgot this, and carried on using them slavishly anyway. Now it's a sign of cheap crap where the designers aren't fully aware of what they're doing. Like those UK plugs they make, with insulation sleeves on the earth pin.
$endgroup$
– Greenaum
Sep 19 at 4:50
$begingroup$
Incidentally, you can get cheap cigarette lighters with a LED torch in the base. Just an LED and a few tiny batteries, with a springy metal contact for the switch. Usually they're white. But some come with a blue LED, even though blue is the colour the human eye can see least. Green, or better, yellow, would be a better choice if you can't have white. But they use blue ones. A blue torch. What's the point? I suppose it's because they use the same higher voltage as white so can use the same battery arrangement. Even though you can't actually use them to see with. Oh, China!
$endgroup$
– Greenaum
Sep 19 at 4:54
add a comment
|
$begingroup$
If your equipment is mains voltage, no low-voltage DC available, a neon is a lot easier. As Dave Tweed said, for one thing the resistor can be smaller. Neons can also tolerate the odd voltage surge, and other out-of-spec conditions. An LED has a delicate and tiny structure necessary to it's function. A neon is just some gas and 2 bits of copper.
Things like kettles, radiators, etc, that are mains-only, typically use neons. If it's cheap garbage from Ebay / Amazon, they might (ab)use an LED cos it's cheaper and they don't care about reliability. But why do they always choose blue?
answered Sep 18 at 6:13
GreenaumGreenaum
2911 silver badge5 bronze badges
$endgroup$
2
$begingroup$
Red, or green, will make (at least some) people think of a meaning (red for some error, green for ok (in the sense of "something was actually checked and found ok)). Blue doesn't have that problem.
$endgroup$
– Guntram Blohm supports Monica
Sep 18 at 12:22
2
$begingroup$
Blue is cruise control for cool.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:13
1
$begingroup$
Blue is cruise control for insomnia and headaches from chromatic aberration.
$endgroup$
– R..
Sep 19 at 0:26
1
$begingroup$
I think what it is, is blue LEDs were hideously expensive, 20 years ago, til that Japanese bloke discovered a way of making them cheaply. And got a Nobel Prize for it. Even when his process was implemented, they were expensive for a while. So blue LED = flashy! quality! much chrominance! Then the Chinese forgot this, and carried on using them slavishly anyway. Now it's a sign of cheap crap where the designers aren't fully aware of what they're doing. Like those UK plugs they make, with insulation sleeves on the earth pin.
$endgroup$
– Greenaum
Sep 19 at 4:50
$begingroup$
Incidentally, you can get cheap cigarette lighters with a LED torch in the base. Just an LED and a few tiny batteries, with a springy metal contact for the switch. Usually they're white. But some come with a blue LED, even though blue is the colour the human eye can see least. Green, or better, yellow, would be a better choice if you can't have white. But they use blue ones. A blue torch. What's the point? I suppose it's because they use the same higher voltage as white so can use the same battery arrangement. Even though you can't actually use them to see with. Oh, China!
$endgroup$
– Greenaum
Sep 19 at 4:54
add a comment
|
$begingroup$
If your equipment is mains voltage, no low-voltage DC available, a neon is a lot easier. As Dave Tweed said, for one thing the resistor can be smaller. Neons can also tolerate the odd voltage surge, and other out-of-spec conditions. An LED has a delicate and tiny structure necessary to it's function. A neon is just some gas and 2 bits of copper.
Things like kettles, radiators, etc, that are mains-only, typically use neons. If it's cheap garbage from Ebay / Amazon, they might (ab)use an LED cos it's cheaper and they don't care about reliability. But why do they always choose blue?
answered Sep 18 at 6:13
GreenaumGreenaum
2911 silver badge5 bronze badges
$endgroup$
If your equipment is mains voltage, no low-voltage DC available, a neon is a lot easier. As Dave Tweed said, for one thing the resistor can be smaller. Neons can also tolerate the odd voltage surge, and other out-of-spec conditions. An LED has a delicate and tiny structure necessary to it's function. A neon is just some gas and 2 bits of copper.
Things like kettles, radiators, etc, that are mains-only, typically use neons. If it's cheap garbage from Ebay / Amazon, they might (ab)use an LED cos it's cheaper and they don't care about reliability. But why do they always choose blue?
answered Sep 18 at 6:13
GreenaumGreenaum
2911 silver badge5 bronze badges
answered Sep 18 at 6:13
GreenaumGreenaum
2911 silver badge5 bronze badges
answered Sep 18 at 6:13
GreenaumGreenaum
2911 silver badge5 bronze badges
answered Sep 18 at 6:13
GreenaumGreenaum
2911 silver badge5 bronze badges
2911 silver badge5 bronze badges
2
$begingroup$
Red, or green, will make (at least some) people think of a meaning (red for some error, green for ok (in the sense of "something was actually checked and found ok)). Blue doesn't have that problem.
$endgroup$
– Guntram Blohm supports Monica
Sep 18 at 12:22
2
$begingroup$
Blue is cruise control for cool.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:13
1
$begingroup$
Blue is cruise control for insomnia and headaches from chromatic aberration.
$endgroup$
– R..
Sep 19 at 0:26
1
$begingroup$
I think what it is, is blue LEDs were hideously expensive, 20 years ago, til that Japanese bloke discovered a way of making them cheaply. And got a Nobel Prize for it. Even when his process was implemented, they were expensive for a while. So blue LED = flashy! quality! much chrominance! Then the Chinese forgot this, and carried on using them slavishly anyway. Now it's a sign of cheap crap where the designers aren't fully aware of what they're doing. Like those UK plugs they make, with insulation sleeves on the earth pin.
$endgroup$
– Greenaum
Sep 19 at 4:50
$begingroup$
Incidentally, you can get cheap cigarette lighters with a LED torch in the base. Just an LED and a few tiny batteries, with a springy metal contact for the switch. Usually they're white. But some come with a blue LED, even though blue is the colour the human eye can see least. Green, or better, yellow, would be a better choice if you can't have white. But they use blue ones. A blue torch. What's the point? I suppose it's because they use the same higher voltage as white so can use the same battery arrangement. Even though you can't actually use them to see with. Oh, China!
$endgroup$
– Greenaum
Sep 19 at 4:54
add a comment
|
2
$begingroup$
Red, or green, will make (at least some) people think of a meaning (red for some error, green for ok (in the sense of "something was actually checked and found ok)). Blue doesn't have that problem.
$endgroup$
– Guntram Blohm supports Monica
Sep 18 at 12:22
2
$begingroup$
Blue is cruise control for cool.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:13
1
$begingroup$
Blue is cruise control for insomnia and headaches from chromatic aberration.
$endgroup$
– R..
Sep 19 at 0:26
1
$begingroup$
I think what it is, is blue LEDs were hideously expensive, 20 years ago, til that Japanese bloke discovered a way of making them cheaply. And got a Nobel Prize for it. Even when his process was implemented, they were expensive for a while. So blue LED = flashy! quality! much chrominance! Then the Chinese forgot this, and carried on using them slavishly anyway. Now it's a sign of cheap crap where the designers aren't fully aware of what they're doing. Like those UK plugs they make, with insulation sleeves on the earth pin.
$endgroup$
– Greenaum
Sep 19 at 4:50
$begingroup$
Incidentally, you can get cheap cigarette lighters with a LED torch in the base. Just an LED and a few tiny batteries, with a springy metal contact for the switch. Usually they're white. But some come with a blue LED, even though blue is the colour the human eye can see least. Green, or better, yellow, would be a better choice if you can't have white. But they use blue ones. A blue torch. What's the point? I suppose it's because they use the same higher voltage as white so can use the same battery arrangement. Even though you can't actually use them to see with. Oh, China!
$endgroup$
– Greenaum
Sep 19 at 4:54
2
2
$begingroup$
Red, or green, will make (at least some) people think of a meaning (red for some error, green for ok (in the sense of "something was actually checked and found ok)). Blue doesn't have that problem.
$endgroup$
– Guntram Blohm supports Monica
Sep 18 at 12:22
$begingroup$
Red, or green, will make (at least some) people think of a meaning (red for some error, green for ok (in the sense of "something was actually checked and found ok)). Blue doesn't have that problem.
$endgroup$
– Guntram Blohm supports Monica
Sep 18 at 12:22
2
2
$begingroup$
Blue is cruise control for cool.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:13
$begingroup$
Blue is cruise control for cool.
$endgroup$
– Harper - Reinstate Monica
Sep 18 at 20:13
1
1
$begingroup$
Blue is cruise control for insomnia and headaches from chromatic aberration.
$endgroup$
– R..
Sep 19 at 0:26
$begingroup$
Blue is cruise control for insomnia and headaches from chromatic aberration.
$endgroup$
– R..
Sep 19 at 0:26
1
1
$begingroup$
I think what it is, is blue LEDs were hideously expensive, 20 years ago, til that Japanese bloke discovered a way of making them cheaply. And got a Nobel Prize for it. Even when his process was implemented, they were expensive for a while. So blue LED = flashy! quality! much chrominance! Then the Chinese forgot this, and carried on using them slavishly anyway. Now it's a sign of cheap crap where the designers aren't fully aware of what they're doing. Like those UK plugs they make, with insulation sleeves on the earth pin.
$endgroup$
– Greenaum
Sep 19 at 4:50
$begingroup$
I think what it is, is blue LEDs were hideously expensive, 20 years ago, til that Japanese bloke discovered a way of making them cheaply. And got a Nobel Prize for it. Even when his process was implemented, they were expensive for a while. So blue LED = flashy! quality! much chrominance! Then the Chinese forgot this, and carried on using them slavishly anyway. Now it's a sign of cheap crap where the designers aren't fully aware of what they're doing. Like those UK plugs they make, with insulation sleeves on the earth pin.
$endgroup$
– Greenaum
Sep 19 at 4:50
$begingroup$
Incidentally, you can get cheap cigarette lighters with a LED torch in the base. Just an LED and a few tiny batteries, with a springy metal contact for the switch. Usually they're white. But some come with a blue LED, even though blue is the colour the human eye can see least. Green, or better, yellow, would be a better choice if you can't have white. But they use blue ones. A blue torch. What's the point? I suppose it's because they use the same higher voltage as white so can use the same battery arrangement. Even though you can't actually use them to see with. Oh, China!
$endgroup$
– Greenaum
Sep 19 at 4:54
$begingroup$
Incidentally, you can get cheap cigarette lighters with a LED torch in the base. Just an LED and a few tiny batteries, with a springy metal contact for the switch. Usually they're white. But some come with a blue LED, even though blue is the colour the human eye can see least. Green, or better, yellow, would be a better choice if you can't have white. But they use blue ones. A blue torch. What's the point? I suppose it's because they use the same higher voltage as white so can use the same battery arrangement. Even though you can't actually use them to see with. Oh, China!
$endgroup$
– Greenaum
Sep 19 at 4:54
add a comment
|
$begingroup$
The need for neons can be related to the industry. For example, equipment that wears out in nuclear facilities must typically be replaced with identical gear, because the cost of qualifying new equipment to operate in the system is so great that it makes no sense to use anything but the old design. If the old design had neons, the replacement typically will too.
The need for neons can also be cosmetic. I build nixie tube clocks for friends and use neons for the colon separating hours and minutes. The color closely matches the color from the nixie filaments, and LEDs just wouldn't look as good.
They also have very low current draw and so are sometimes used as indicators in older designs in emergency power or ride-through applications.
answered Sep 18 at 14:09
schadjoschadjo
9902 silver badges13 bronze badges
$endgroup$
1
$begingroup$
less relevant to your answer itself, but relevant to your anecdote: there are red-orange LEDs out there that very closely match the color of neon/nixie tubes; since neons have spectral peaks around 600nm, 625nm, and 650nm, try looking specifically for an LED with a wavelength of 600-650nm; places like Mouser let you filter by wavelength(s).
$endgroup$
– Doktor J
Sep 18 at 21:13
1
$begingroup$
That's helpful but I bet they don't have the same flicker! Neons just have an indefinable unique quality. Nothing else is quite the same. And they're nice, people like them. Maybe it's just nostalgia. Actually on a nixie clock it probably is!
$endgroup$
– Greenaum
Sep 19 at 4:56
$begingroup$
@Doktor Thanks for the heads-up.
$endgroup$
– schadjo
Sep 19 at 12:15
1
$begingroup$
At that Mouser link, there are some red/yellow bi-color LEDs that might better emulate the spectral emission of neon lamps. Putting the LEDs on half-rectified DC, perhaps with a small and not-wholly-adequate smoothing capacitor, could emulate the flicker too. Using $V_ripple = fracI_loadmathitf times C$ if we accept ~1V ripple and our input frequency is 60Hz, and the LEDs use 20mA, $1V = frac0.02A60Hz times C$, $1 times 60 = frac0.02C$, $60 times C = 0.02$, $C = frac0.0260 = 0.0003F$ or 300uF; so a 200-300uF cap would give you some good soft flicker.
$endgroup$
– Doktor J
Sep 24 at 18:22
add a comment
|
$begingroup$
The need for neons can be related to the industry. For example, equipment that wears out in nuclear facilities must typically be replaced with identical gear, because the cost of qualifying new equipment to operate in the system is so great that it makes no sense to use anything but the old design. If the old design had neons, the replacement typically will too.
The need for neons can also be cosmetic. I build nixie tube clocks for friends and use neons for the colon separating hours and minutes. The color closely matches the color from the nixie filaments, and LEDs just wouldn't look as good.
They also have very low current draw and so are sometimes used as indicators in older designs in emergency power or ride-through applications.
answered Sep 18 at 14:09
schadjoschadjo
9902 silver badges13 bronze badges
$endgroup$
1
$begingroup$
less relevant to your answer itself, but relevant to your anecdote: there are red-orange LEDs out there that very closely match the color of neon/nixie tubes; since neons have spectral peaks around 600nm, 625nm, and 650nm, try looking specifically for an LED with a wavelength of 600-650nm; places like Mouser let you filter by wavelength(s).
$endgroup$
– Doktor J
Sep 18 at 21:13
1
$begingroup$
That's helpful but I bet they don't have the same flicker! Neons just have an indefinable unique quality. Nothing else is quite the same. And they're nice, people like them. Maybe it's just nostalgia. Actually on a nixie clock it probably is!
$endgroup$
– Greenaum
Sep 19 at 4:56
$begingroup$
@Doktor Thanks for the heads-up.
$endgroup$
– schadjo
Sep 19 at 12:15
1
$begingroup$
At that Mouser link, there are some red/yellow bi-color LEDs that might better emulate the spectral emission of neon lamps. Putting the LEDs on half-rectified DC, perhaps with a small and not-wholly-adequate smoothing capacitor, could emulate the flicker too. Using $V_ripple = fracI_loadmathitf times C$ if we accept ~1V ripple and our input frequency is 60Hz, and the LEDs use 20mA, $1V = frac0.02A60Hz times C$, $1 times 60 = frac0.02C$, $60 times C = 0.02$, $C = frac0.0260 = 0.0003F$ or 300uF; so a 200-300uF cap would give you some good soft flicker.
$endgroup$
– Doktor J
Sep 24 at 18:22
add a comment
|
$begingroup$
The need for neons can be related to the industry. For example, equipment that wears out in nuclear facilities must typically be replaced with identical gear, because the cost of qualifying new equipment to operate in the system is so great that it makes no sense to use anything but the old design. If the old design had neons, the replacement typically will too.
The need for neons can also be cosmetic. I build nixie tube clocks for friends and use neons for the colon separating hours and minutes. The color closely matches the color from the nixie filaments, and LEDs just wouldn't look as good.
They also have very low current draw and so are sometimes used as indicators in older designs in emergency power or ride-through applications.
answered Sep 18 at 14:09
schadjoschadjo
9902 silver badges13 bronze badges
$endgroup$
The need for neons can be related to the industry. For example, equipment that wears out in nuclear facilities must typically be replaced with identical gear, because the cost of qualifying new equipment to operate in the system is so great that it makes no sense to use anything but the old design. If the old design had neons, the replacement typically will too.
The need for neons can also be cosmetic. I build nixie tube clocks for friends and use neons for the colon separating hours and minutes. The color closely matches the color from the nixie filaments, and LEDs just wouldn't look as good.
They also have very low current draw and so are sometimes used as indicators in older designs in emergency power or ride-through applications.
answered Sep 18 at 14:09
schadjoschadjo
9902 silver badges13 bronze badges
answered Sep 18 at 14:09
schadjoschadjo
9902 silver badges13 bronze badges
answered Sep 18 at 14:09
schadjoschadjo
9902 silver badges13 bronze badges
answered Sep 18 at 14:09
schadjoschadjo
9902 silver badges13 bronze badges
9902 silver badges13 bronze badges
1
$begingroup$
less relevant to your answer itself, but relevant to your anecdote: there are red-orange LEDs out there that very closely match the color of neon/nixie tubes; since neons have spectral peaks around 600nm, 625nm, and 650nm, try looking specifically for an LED with a wavelength of 600-650nm; places like Mouser let you filter by wavelength(s).
$endgroup$
– Doktor J
Sep 18 at 21:13
1
$begingroup$
That's helpful but I bet they don't have the same flicker! Neons just have an indefinable unique quality. Nothing else is quite the same. And they're nice, people like them. Maybe it's just nostalgia. Actually on a nixie clock it probably is!
$endgroup$
– Greenaum
Sep 19 at 4:56
$begingroup$
@Doktor Thanks for the heads-up.
$endgroup$
– schadjo
Sep 19 at 12:15
1
$begingroup$
At that Mouser link, there are some red/yellow bi-color LEDs that might better emulate the spectral emission of neon lamps. Putting the LEDs on half-rectified DC, perhaps with a small and not-wholly-adequate smoothing capacitor, could emulate the flicker too. Using $V_ripple = fracI_loadmathitf times C$ if we accept ~1V ripple and our input frequency is 60Hz, and the LEDs use 20mA, $1V = frac0.02A60Hz times C$, $1 times 60 = frac0.02C$, $60 times C = 0.02$, $C = frac0.0260 = 0.0003F$ or 300uF; so a 200-300uF cap would give you some good soft flicker.
$endgroup$
– Doktor J
Sep 24 at 18:22
add a comment
|
1
$begingroup$
less relevant to your answer itself, but relevant to your anecdote: there are red-orange LEDs out there that very closely match the color of neon/nixie tubes; since neons have spectral peaks around 600nm, 625nm, and 650nm, try looking specifically for an LED with a wavelength of 600-650nm; places like Mouser let you filter by wavelength(s).
$endgroup$
– Doktor J
Sep 18 at 21:13
1
$begingroup$
That's helpful but I bet they don't have the same flicker! Neons just have an indefinable unique quality. Nothing else is quite the same. And they're nice, people like them. Maybe it's just nostalgia. Actually on a nixie clock it probably is!
$endgroup$
– Greenaum
Sep 19 at 4:56
$begingroup$
@Doktor Thanks for the heads-up.
$endgroup$
– schadjo
Sep 19 at 12:15
1
$begingroup$
At that Mouser link, there are some red/yellow bi-color LEDs that might better emulate the spectral emission of neon lamps. Putting the LEDs on half-rectified DC, perhaps with a small and not-wholly-adequate smoothing capacitor, could emulate the flicker too. Using $V_ripple = fracI_loadmathitf times C$ if we accept ~1V ripple and our input frequency is 60Hz, and the LEDs use 20mA, $1V = frac0.02A60Hz times C$, $1 times 60 = frac0.02C$, $60 times C = 0.02$, $C = frac0.0260 = 0.0003F$ or 300uF; so a 200-300uF cap would give you some good soft flicker.
$endgroup$
– Doktor J
Sep 24 at 18:22
1
1
$begingroup$
less relevant to your answer itself, but relevant to your anecdote: there are red-orange LEDs out there that very closely match the color of neon/nixie tubes; since neons have spectral peaks around 600nm, 625nm, and 650nm, try looking specifically for an LED with a wavelength of 600-650nm; places like Mouser let you filter by wavelength(s).
$endgroup$
– Doktor J
Sep 18 at 21:13
$begingroup$
less relevant to your answer itself, but relevant to your anecdote: there are red-orange LEDs out there that very closely match the color of neon/nixie tubes; since neons have spectral peaks around 600nm, 625nm, and 650nm, try looking specifically for an LED with a wavelength of 600-650nm; places like Mouser let you filter by wavelength(s).
$endgroup$
– Doktor J
Sep 18 at 21:13
1
1
$begingroup$
That's helpful but I bet they don't have the same flicker! Neons just have an indefinable unique quality. Nothing else is quite the same. And they're nice, people like them. Maybe it's just nostalgia. Actually on a nixie clock it probably is!
$endgroup$
– Greenaum
Sep 19 at 4:56
$begingroup$
That's helpful but I bet they don't have the same flicker! Neons just have an indefinable unique quality. Nothing else is quite the same. And they're nice, people like them. Maybe it's just nostalgia. Actually on a nixie clock it probably is!
$endgroup$
– Greenaum
Sep 19 at 4:56
$begingroup$
@Doktor Thanks for the heads-up.
$endgroup$
– schadjo
Sep 19 at 12:15
$begingroup$
@Doktor Thanks for the heads-up.
$endgroup$
– schadjo
Sep 19 at 12:15
1
1
$begingroup$
At that Mouser link, there are some red/yellow bi-color LEDs that might better emulate the spectral emission of neon lamps. Putting the LEDs on half-rectified DC, perhaps with a small and not-wholly-adequate smoothing capacitor, could emulate the flicker too. Using $V_ripple = fracI_loadmathitf times C$ if we accept ~1V ripple and our input frequency is 60Hz, and the LEDs use 20mA, $1V = frac0.02A60Hz times C$, $1 times 60 = frac0.02C$, $60 times C = 0.02$, $C = frac0.0260 = 0.0003F$ or 300uF; so a 200-300uF cap would give you some good soft flicker.
$endgroup$
– Doktor J
Sep 24 at 18:22
$begingroup$
At that Mouser link, there are some red/yellow bi-color LEDs that might better emulate the spectral emission of neon lamps. Putting the LEDs on half-rectified DC, perhaps with a small and not-wholly-adequate smoothing capacitor, could emulate the flicker too. Using $V_ripple = fracI_loadmathitf times C$ if we accept ~1V ripple and our input frequency is 60Hz, and the LEDs use 20mA, $1V = frac0.02A60Hz times C$, $1 times 60 = frac0.02C$, $60 times C = 0.02$, $C = frac0.0260 = 0.0003F$ or 300uF; so a 200-300uF cap would give you some good soft flicker.
$endgroup$
– Doktor J
Sep 24 at 18:22
add a comment
|
$begingroup$
Have you actually tried building mains neon vs LED indicators? I bet you haven't.
Here, try a project. Sometimes, a leg of split-phase or 3-phase AC power will drop out at the poletop. Either neutral gets lost, causing L1 to rise and L2 drop, or a leg is lost, causing L1 to be backfed through 240V appliances. Make a very useful gadget that grabs L1, L2 and N, and visually indicates whether L1-N and L2-N are very coarsely the same voltage, and L1-L2 is coarsely 2x the others. The user switches off breakers and watches to see if that affects brightness one to the other. Having 3-4 lights and having the user watch for differences in brightness is fine. Durability a million hours. Needs to be simple and very low parasitic load, energy budget 720mW (3ma). Go.
However, your point is fair that 99% of electronics innovation is done on the low-voltage side of the wall wart. Neon has no place there; it would need an active circuit driving it, and that compares disfavorably with LED.
Neon and LED are different indicator types for different regimes of electricity. When you argue against neon, you're arguing against mains voltage as a supply source. As a big fan of houses having low voltage DC systems so they can happily exist in power-out situations without generators or inverters -- I can't really disagree.
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
8,49711 silver badges34 bronze badges
$endgroup$
$begingroup$
The problem with low-voltage DC systems is the voltage drop. You're using much more current, MUCH more! So the voltage drops get huge, and you'd have to run cable like the stuff on a car battery, if you were gonna start powering all electronics from it. High voltage is much better for distribution. It's like a microcosm of the electrical grid. The longer the distance, the higher the voltage they use. It's the same at home, a scale of dozens of metres means some high voltage, low current, system wins. It's best to convert to DC at point of use. And pretty cheap too.
$endgroup$
– Greenaum
Sep 19 at 5:01
1
$begingroup$
We don't have split-phase AC in Europe (in fact, I have 3-phase lines directly to my energy meter), so the issue you mention was completely unknown to me.
$endgroup$
– FarO
Sep 19 at 8:23
$begingroup$
@FarO then do it 3-phase, it's just one more phase. European houses also lose phases and neutral. Bonus points for getting the 400V lights to be the same brightness as 230V. And have more energy budget; 2000mw. Visible indicator (differential brightness is fine) for a lost phase or neutral, given that 3-phase appliances will backfeed the dead phase.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:04
1
$begingroup$
@Greenaum yes, you have to be selective about what you're powering, but lighting and electroncs loads are no problem. For others it is a matter of competent design. HVAC: passive solar design, water heater: gas or solar, etc. LVDC as a unit replacement for buffoonishly designed all-electric homes won't work, obviously.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:18
add a comment
|
$begingroup$
Have you actually tried building mains neon vs LED indicators? I bet you haven't.
Here, try a project. Sometimes, a leg of split-phase or 3-phase AC power will drop out at the poletop. Either neutral gets lost, causing L1 to rise and L2 drop, or a leg is lost, causing L1 to be backfed through 240V appliances. Make a very useful gadget that grabs L1, L2 and N, and visually indicates whether L1-N and L2-N are very coarsely the same voltage, and L1-L2 is coarsely 2x the others. The user switches off breakers and watches to see if that affects brightness one to the other. Having 3-4 lights and having the user watch for differences in brightness is fine. Durability a million hours. Needs to be simple and very low parasitic load, energy budget 720mW (3ma). Go.
However, your point is fair that 99% of electronics innovation is done on the low-voltage side of the wall wart. Neon has no place there; it would need an active circuit driving it, and that compares disfavorably with LED.
Neon and LED are different indicator types for different regimes of electricity. When you argue against neon, you're arguing against mains voltage as a supply source. As a big fan of houses having low voltage DC systems so they can happily exist in power-out situations without generators or inverters -- I can't really disagree.
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
8,49711 silver badges34 bronze badges
$endgroup$
$begingroup$
The problem with low-voltage DC systems is the voltage drop. You're using much more current, MUCH more! So the voltage drops get huge, and you'd have to run cable like the stuff on a car battery, if you were gonna start powering all electronics from it. High voltage is much better for distribution. It's like a microcosm of the electrical grid. The longer the distance, the higher the voltage they use. It's the same at home, a scale of dozens of metres means some high voltage, low current, system wins. It's best to convert to DC at point of use. And pretty cheap too.
$endgroup$
– Greenaum
Sep 19 at 5:01
1
$begingroup$
We don't have split-phase AC in Europe (in fact, I have 3-phase lines directly to my energy meter), so the issue you mention was completely unknown to me.
$endgroup$
– FarO
Sep 19 at 8:23
$begingroup$
@FarO then do it 3-phase, it's just one more phase. European houses also lose phases and neutral. Bonus points for getting the 400V lights to be the same brightness as 230V. And have more energy budget; 2000mw. Visible indicator (differential brightness is fine) for a lost phase or neutral, given that 3-phase appliances will backfeed the dead phase.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:04
1
$begingroup$
@Greenaum yes, you have to be selective about what you're powering, but lighting and electroncs loads are no problem. For others it is a matter of competent design. HVAC: passive solar design, water heater: gas or solar, etc. LVDC as a unit replacement for buffoonishly designed all-electric homes won't work, obviously.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:18
add a comment
|
$begingroup$
Have you actually tried building mains neon vs LED indicators? I bet you haven't.
Here, try a project. Sometimes, a leg of split-phase or 3-phase AC power will drop out at the poletop. Either neutral gets lost, causing L1 to rise and L2 drop, or a leg is lost, causing L1 to be backfed through 240V appliances. Make a very useful gadget that grabs L1, L2 and N, and visually indicates whether L1-N and L2-N are very coarsely the same voltage, and L1-L2 is coarsely 2x the others. The user switches off breakers and watches to see if that affects brightness one to the other. Having 3-4 lights and having the user watch for differences in brightness is fine. Durability a million hours. Needs to be simple and very low parasitic load, energy budget 720mW (3ma). Go.
However, your point is fair that 99% of electronics innovation is done on the low-voltage side of the wall wart. Neon has no place there; it would need an active circuit driving it, and that compares disfavorably with LED.
Neon and LED are different indicator types for different regimes of electricity. When you argue against neon, you're arguing against mains voltage as a supply source. As a big fan of houses having low voltage DC systems so they can happily exist in power-out situations without generators or inverters -- I can't really disagree.
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
8,49711 silver badges34 bronze badges
$endgroup$
Have you actually tried building mains neon vs LED indicators? I bet you haven't.
Here, try a project. Sometimes, a leg of split-phase or 3-phase AC power will drop out at the poletop. Either neutral gets lost, causing L1 to rise and L2 drop, or a leg is lost, causing L1 to be backfed through 240V appliances. Make a very useful gadget that grabs L1, L2 and N, and visually indicates whether L1-N and L2-N are very coarsely the same voltage, and L1-L2 is coarsely 2x the others. The user switches off breakers and watches to see if that affects brightness one to the other. Having 3-4 lights and having the user watch for differences in brightness is fine. Durability a million hours. Needs to be simple and very low parasitic load, energy budget 720mW (3ma). Go.
However, your point is fair that 99% of electronics innovation is done on the low-voltage side of the wall wart. Neon has no place there; it would need an active circuit driving it, and that compares disfavorably with LED.
Neon and LED are different indicator types for different regimes of electricity. When you argue against neon, you're arguing against mains voltage as a supply source. As a big fan of houses having low voltage DC systems so they can happily exist in power-out situations without generators or inverters -- I can't really disagree.
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
8,49711 silver badges34 bronze badges
edited Sep 19 at 15:59
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
8,49711 silver badges34 bronze badges
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
8,49711 silver badges34 bronze badges
answered Sep 18 at 21:58
Harper - Reinstate MonicaHarper - Reinstate Monica
8,49711 silver badges34 bronze badges
8,49711 silver badges34 bronze badges
$begingroup$
The problem with low-voltage DC systems is the voltage drop. You're using much more current, MUCH more! So the voltage drops get huge, and you'd have to run cable like the stuff on a car battery, if you were gonna start powering all electronics from it. High voltage is much better for distribution. It's like a microcosm of the electrical grid. The longer the distance, the higher the voltage they use. It's the same at home, a scale of dozens of metres means some high voltage, low current, system wins. It's best to convert to DC at point of use. And pretty cheap too.
$endgroup$
– Greenaum
Sep 19 at 5:01
1
$begingroup$
We don't have split-phase AC in Europe (in fact, I have 3-phase lines directly to my energy meter), so the issue you mention was completely unknown to me.
$endgroup$
– FarO
Sep 19 at 8:23
$begingroup$
@FarO then do it 3-phase, it's just one more phase. European houses also lose phases and neutral. Bonus points for getting the 400V lights to be the same brightness as 230V. And have more energy budget; 2000mw. Visible indicator (differential brightness is fine) for a lost phase or neutral, given that 3-phase appliances will backfeed the dead phase.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:04
1
$begingroup$
@Greenaum yes, you have to be selective about what you're powering, but lighting and electroncs loads are no problem. For others it is a matter of competent design. HVAC: passive solar design, water heater: gas or solar, etc. LVDC as a unit replacement for buffoonishly designed all-electric homes won't work, obviously.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:18
add a comment
|
$begingroup$
The problem with low-voltage DC systems is the voltage drop. You're using much more current, MUCH more! So the voltage drops get huge, and you'd have to run cable like the stuff on a car battery, if you were gonna start powering all electronics from it. High voltage is much better for distribution. It's like a microcosm of the electrical grid. The longer the distance, the higher the voltage they use. It's the same at home, a scale of dozens of metres means some high voltage, low current, system wins. It's best to convert to DC at point of use. And pretty cheap too.
$endgroup$
– Greenaum
Sep 19 at 5:01
1
$begingroup$
We don't have split-phase AC in Europe (in fact, I have 3-phase lines directly to my energy meter), so the issue you mention was completely unknown to me.
$endgroup$
– FarO
Sep 19 at 8:23
$begingroup$
@FarO then do it 3-phase, it's just one more phase. European houses also lose phases and neutral. Bonus points for getting the 400V lights to be the same brightness as 230V. And have more energy budget; 2000mw. Visible indicator (differential brightness is fine) for a lost phase or neutral, given that 3-phase appliances will backfeed the dead phase.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:04
1
$begingroup$
@Greenaum yes, you have to be selective about what you're powering, but lighting and electroncs loads are no problem. For others it is a matter of competent design. HVAC: passive solar design, water heater: gas or solar, etc. LVDC as a unit replacement for buffoonishly designed all-electric homes won't work, obviously.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:18
$begingroup$
The problem with low-voltage DC systems is the voltage drop. You're using much more current, MUCH more! So the voltage drops get huge, and you'd have to run cable like the stuff on a car battery, if you were gonna start powering all electronics from it. High voltage is much better for distribution. It's like a microcosm of the electrical grid. The longer the distance, the higher the voltage they use. It's the same at home, a scale of dozens of metres means some high voltage, low current, system wins. It's best to convert to DC at point of use. And pretty cheap too.
$endgroup$
– Greenaum
Sep 19 at 5:01
$begingroup$
The problem with low-voltage DC systems is the voltage drop. You're using much more current, MUCH more! So the voltage drops get huge, and you'd have to run cable like the stuff on a car battery, if you were gonna start powering all electronics from it. High voltage is much better for distribution. It's like a microcosm of the electrical grid. The longer the distance, the higher the voltage they use. It's the same at home, a scale of dozens of metres means some high voltage, low current, system wins. It's best to convert to DC at point of use. And pretty cheap too.
$endgroup$
– Greenaum
Sep 19 at 5:01
1
1
$begingroup$
We don't have split-phase AC in Europe (in fact, I have 3-phase lines directly to my energy meter), so the issue you mention was completely unknown to me.
$endgroup$
– FarO
Sep 19 at 8:23
$begingroup$
We don't have split-phase AC in Europe (in fact, I have 3-phase lines directly to my energy meter), so the issue you mention was completely unknown to me.
$endgroup$
– FarO
Sep 19 at 8:23
$begingroup$
@FarO then do it 3-phase, it's just one more phase. European houses also lose phases and neutral. Bonus points for getting the 400V lights to be the same brightness as 230V. And have more energy budget; 2000mw. Visible indicator (differential brightness is fine) for a lost phase or neutral, given that 3-phase appliances will backfeed the dead phase.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:04
$begingroup$
@FarO then do it 3-phase, it's just one more phase. European houses also lose phases and neutral. Bonus points for getting the 400V lights to be the same brightness as 230V. And have more energy budget; 2000mw. Visible indicator (differential brightness is fine) for a lost phase or neutral, given that 3-phase appliances will backfeed the dead phase.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:04
1
1
$begingroup$
@Greenaum yes, you have to be selective about what you're powering, but lighting and electroncs loads are no problem. For others it is a matter of competent design. HVAC: passive solar design, water heater: gas or solar, etc. LVDC as a unit replacement for buffoonishly designed all-electric homes won't work, obviously.
$endgroup$
– Harper - Reinstate Monica
Sep 19 at 16:18
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@Greenaum yes, you have to be selective about what you're powering, but lighting and electroncs loads are no problem. For others it is a matter of competent design. HVAC: passive solar design, water heater: gas or solar, etc. LVDC as a unit replacement for buffoonishly designed all-electric homes won't work, obviously.
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– Harper - Reinstate Monica
Sep 19 at 16:18
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Most regular LEDs have about 2 Vdc drop in forward mode and need about 1 mA to light up. although 10 mA is recommended with standard LEDs.
In addition, they can only withstand about 2 Vdc in reverse mode, which means that they need a rectifier diode in series to protect them when the ac voltage changes polarity.
In this configuration, the LED lights up only half of the time, which may reduce its brightness; this could be good or bad depending on the application.
Neon lamps use a 100 K to 250 K, 1/4 W resistor (see http://www.farnell.com/datasheets/57560.pdf).
Neon lamps are not that bright and in certain applications may not stand out when lit, especially in highly lit areas.
With time, neon lamps develop flickering and electrode polarization (only one of the electrodes glows).
Neon lamps are available in various base sizes (see https://www.bulbtown.com/neon_lamps_and_light_bulbs_s/909.htm). Some even come with an internal resistor sized for a specific operating voltage.
answered Sep 18 at 13:37
OscarOscar
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Most regular LEDs have about 2 Vdc drop in forward mode and need about 1 mA to light up. although 10 mA is recommended with standard LEDs.
In addition, they can only withstand about 2 Vdc in reverse mode, which means that they need a rectifier diode in series to protect them when the ac voltage changes polarity.
In this configuration, the LED lights up only half of the time, which may reduce its brightness; this could be good or bad depending on the application.
Neon lamps use a 100 K to 250 K, 1/4 W resistor (see http://www.farnell.com/datasheets/57560.pdf).
Neon lamps are not that bright and in certain applications may not stand out when lit, especially in highly lit areas.
With time, neon lamps develop flickering and electrode polarization (only one of the electrodes glows).
Neon lamps are available in various base sizes (see https://www.bulbtown.com/neon_lamps_and_light_bulbs_s/909.htm). Some even come with an internal resistor sized for a specific operating voltage.
answered Sep 18 at 13:37
OscarOscar
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Most regular LEDs have about 2 Vdc drop in forward mode and need about 1 mA to light up. although 10 mA is recommended with standard LEDs.
In addition, they can only withstand about 2 Vdc in reverse mode, which means that they need a rectifier diode in series to protect them when the ac voltage changes polarity.
In this configuration, the LED lights up only half of the time, which may reduce its brightness; this could be good or bad depending on the application.
Neon lamps use a 100 K to 250 K, 1/4 W resistor (see http://www.farnell.com/datasheets/57560.pdf).
Neon lamps are not that bright and in certain applications may not stand out when lit, especially in highly lit areas.
With time, neon lamps develop flickering and electrode polarization (only one of the electrodes glows).
Neon lamps are available in various base sizes (see https://www.bulbtown.com/neon_lamps_and_light_bulbs_s/909.htm). Some even come with an internal resistor sized for a specific operating voltage.
answered Sep 18 at 13:37
OscarOscar
211 bronze badge
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Most regular LEDs have about 2 Vdc drop in forward mode and need about 1 mA to light up. although 10 mA is recommended with standard LEDs.
In addition, they can only withstand about 2 Vdc in reverse mode, which means that they need a rectifier diode in series to protect them when the ac voltage changes polarity.
In this configuration, the LED lights up only half of the time, which may reduce its brightness; this could be good or bad depending on the application.
Neon lamps use a 100 K to 250 K, 1/4 W resistor (see http://www.farnell.com/datasheets/57560.pdf).
Neon lamps are not that bright and in certain applications may not stand out when lit, especially in highly lit areas.
With time, neon lamps develop flickering and electrode polarization (only one of the electrodes glows).
Neon lamps are available in various base sizes (see https://www.bulbtown.com/neon_lamps_and_light_bulbs_s/909.htm). Some even come with an internal resistor sized for a specific operating voltage.
answered Sep 18 at 13:37
OscarOscar
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answered Sep 18 at 13:37
OscarOscar
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answered Sep 18 at 13:37
OscarOscar
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answered Sep 18 at 13:37
OscarOscar
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The current requirements of a Neon are low enough that they can generally be driven directly from the mains with a simple and cheap series resistor.
If you try to drive a LED in a similar way you have at least two problems.
- The reverse breakdown voltage is nowhere near high enough to withstand mains voltages, so you end up having to add another diode (potentially another LED) in inverse-parallel.
- Substantially more current is needed, say 10ma or so which is enough to make a resistive dropper consume unconfortbally large amounts of power. You can solve this by using a a capacitive dropper instead but capacitive droppers have their own issues which require extra components to mitigate.
So neons tend to win out in "pure mains" applications, things like indicators on sockets, plugs, power strips, wall switches, surge protectors, heaters with simple electromechanical thermostats and so-on.
If a device is intelligent enough to have a microcontroller on it then LEDs generally win out.
answered Sep 18 at 13:58
Peter GreenPeter Green
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As a point of clarification, a device "intelligent enough to have a microcontroller on it" already necessarily has a low-voltage DC power rail somewhere, making it trivial to power a LED (even if the µc uses something weird like +15VDC, dropping that with a resistor is trivial)
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– Doktor J
Sep 18 at 21:15
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rainierwolfcastle.jpg
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– Greenaum
Sep 19 at 5:07
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The current requirements of a Neon are low enough that they can generally be driven directly from the mains with a simple and cheap series resistor.
If you try to drive a LED in a similar way you have at least two problems.
- The reverse breakdown voltage is nowhere near high enough to withstand mains voltages, so you end up having to add another diode (potentially another LED) in inverse-parallel.
- Substantially more current is needed, say 10ma or so which is enough to make a resistive dropper consume unconfortbally large amounts of power. You can solve this by using a a capacitive dropper instead but capacitive droppers have their own issues which require extra components to mitigate.
So neons tend to win out in "pure mains" applications, things like indicators on sockets, plugs, power strips, wall switches, surge protectors, heaters with simple electromechanical thermostats and so-on.
If a device is intelligent enough to have a microcontroller on it then LEDs generally win out.
answered Sep 18 at 13:58
Peter GreenPeter Green
13.3k1 gold badge23 silver badges43 bronze badges
$endgroup$
1
$begingroup$
As a point of clarification, a device "intelligent enough to have a microcontroller on it" already necessarily has a low-voltage DC power rail somewhere, making it trivial to power a LED (even if the µc uses something weird like +15VDC, dropping that with a resistor is trivial)
$endgroup$
– Doktor J
Sep 18 at 21:15
$begingroup$
rainierwolfcastle.jpg
$endgroup$
– Greenaum
Sep 19 at 5:07
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The current requirements of a Neon are low enough that they can generally be driven directly from the mains with a simple and cheap series resistor.
If you try to drive a LED in a similar way you have at least two problems.
- The reverse breakdown voltage is nowhere near high enough to withstand mains voltages, so you end up having to add another diode (potentially another LED) in inverse-parallel.
- Substantially more current is needed, say 10ma or so which is enough to make a resistive dropper consume unconfortbally large amounts of power. You can solve this by using a a capacitive dropper instead but capacitive droppers have their own issues which require extra components to mitigate.
So neons tend to win out in "pure mains" applications, things like indicators on sockets, plugs, power strips, wall switches, surge protectors, heaters with simple electromechanical thermostats and so-on.
If a device is intelligent enough to have a microcontroller on it then LEDs generally win out.
answered Sep 18 at 13:58
Peter GreenPeter Green
13.3k1 gold badge23 silver badges43 bronze badges
$endgroup$
The current requirements of a Neon are low enough that they can generally be driven directly from the mains with a simple and cheap series resistor.
If you try to drive a LED in a similar way you have at least two problems.
- The reverse breakdown voltage is nowhere near high enough to withstand mains voltages, so you end up having to add another diode (potentially another LED) in inverse-parallel.
- Substantially more current is needed, say 10ma or so which is enough to make a resistive dropper consume unconfortbally large amounts of power. You can solve this by using a a capacitive dropper instead but capacitive droppers have their own issues which require extra components to mitigate.
So neons tend to win out in "pure mains" applications, things like indicators on sockets, plugs, power strips, wall switches, surge protectors, heaters with simple electromechanical thermostats and so-on.
If a device is intelligent enough to have a microcontroller on it then LEDs generally win out.
answered Sep 18 at 13:58
Peter GreenPeter Green
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edited Sep 18 at 15:42
answered Sep 18 at 13:58
Peter GreenPeter Green
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answered Sep 18 at 13:58
Peter GreenPeter Green
13.3k1 gold badge23 silver badges43 bronze badges
answered Sep 18 at 13:58
Peter GreenPeter Green
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13.3k1 gold badge23 silver badges43 bronze badges
1
$begingroup$
As a point of clarification, a device "intelligent enough to have a microcontroller on it" already necessarily has a low-voltage DC power rail somewhere, making it trivial to power a LED (even if the µc uses something weird like +15VDC, dropping that with a resistor is trivial)
$endgroup$
– Doktor J
Sep 18 at 21:15
$begingroup$
rainierwolfcastle.jpg
$endgroup$
– Greenaum
Sep 19 at 5:07
add a comment
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1
$begingroup$
As a point of clarification, a device "intelligent enough to have a microcontroller on it" already necessarily has a low-voltage DC power rail somewhere, making it trivial to power a LED (even if the µc uses something weird like +15VDC, dropping that with a resistor is trivial)
$endgroup$
– Doktor J
Sep 18 at 21:15
$begingroup$
rainierwolfcastle.jpg
$endgroup$
– Greenaum
Sep 19 at 5:07
1
1
$begingroup$
As a point of clarification, a device "intelligent enough to have a microcontroller on it" already necessarily has a low-voltage DC power rail somewhere, making it trivial to power a LED (even if the µc uses something weird like +15VDC, dropping that with a resistor is trivial)
$endgroup$
– Doktor J
Sep 18 at 21:15
$begingroup$
As a point of clarification, a device "intelligent enough to have a microcontroller on it" already necessarily has a low-voltage DC power rail somewhere, making it trivial to power a LED (even if the µc uses something weird like +15VDC, dropping that with a resistor is trivial)
$endgroup$
– Doktor J
Sep 18 at 21:15
$begingroup$
rainierwolfcastle.jpg
$endgroup$
– Greenaum
Sep 19 at 5:07
$begingroup$
rainierwolfcastle.jpg
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– Greenaum
Sep 19 at 5:07
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Several answers have already discussed the technical reasons, but they don't discuss the applications where those reasons would apply.
A lot of times, you'll see Neon indicators in industrial-grade machinery, for three reasons, two already mentioned:
- Cheaper / easier to drive directly from main voltage (this is important as main voltage rises, like 480V 3-phase systems);
- When under-driven, lifetime is extended substantially;
Simpler installation and circuitry (you can run neons directly off 480V / 277V AC with proper resistors);
As a result, industrial applications using these higher-voltages (note that ANSI still considers 480V a "low-voltage") can save power and cost with appropriately sized neon's. (Sure, it's minimal savings, but typically you need a reason to change something, not keep it the same.)
There are some other curious aspects of industrial systems that generally hold true as well:
- A lot of the logic is 24V DC or 24V AC using relays instead of transistors, easy to drop neons right in;
- The logic often activates raw 480V AC (or 277V AC) equipment -- again, easy to drop a neon in;
- Safety is always a critical issue, because these are often large, dangerous pieces of equipment, so if the bulb dies there should be a possible backup -- once again trivial with neons;
- Industrial equipment is generally expected to take a less-skilled person to service it than smaller electronics (like computers, etc.) -- neons have very common hot-swap plugs on them (LED's are often soldered);
- Industrial equipment may not even have a DC line! -- this means you have to rectify the AC for every LED;
When these aspects are considered, it should make it easier to see why a good chunk of (especially older) industrial-grade equipment would prefer neons to LED's. Especially when considering that if a neon "dies", it's often just extremely dim (vs. completely off as an LED typically is) so it still has minimal functionality.
As an example and anecdote, when I was building the glass manufacturing machines, one feature our machines had was that when plugged in, there was an indicator system that told you if the 480V outlet you plugged into was wired properly. It was extremely cheap to build with Neon's (a few lights and resistors), but would have been slightly more costly (and complex) to build with LED's. (Sure, considering the cost of the machine it was barely noticeable so who cares, but we had no reason to use LED's there and this system has been used by the company for decades, so why spend extra time and money designing a new one?)
Source: I used to maintain and build industrial machinery for a plastic injection molding facility, and a glass machine manufacturing facility.
answered Sep 18 at 21:54
410_Gone410_Gone
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Several answers have already discussed the technical reasons, but they don't discuss the applications where those reasons would apply.
A lot of times, you'll see Neon indicators in industrial-grade machinery, for three reasons, two already mentioned:
- Cheaper / easier to drive directly from main voltage (this is important as main voltage rises, like 480V 3-phase systems);
- When under-driven, lifetime is extended substantially;
Simpler installation and circuitry (you can run neons directly off 480V / 277V AC with proper resistors);
As a result, industrial applications using these higher-voltages (note that ANSI still considers 480V a "low-voltage") can save power and cost with appropriately sized neon's. (Sure, it's minimal savings, but typically you need a reason to change something, not keep it the same.)
There are some other curious aspects of industrial systems that generally hold true as well:
- A lot of the logic is 24V DC or 24V AC using relays instead of transistors, easy to drop neons right in;
- The logic often activates raw 480V AC (or 277V AC) equipment -- again, easy to drop a neon in;
- Safety is always a critical issue, because these are often large, dangerous pieces of equipment, so if the bulb dies there should be a possible backup -- once again trivial with neons;
- Industrial equipment is generally expected to take a less-skilled person to service it than smaller electronics (like computers, etc.) -- neons have very common hot-swap plugs on them (LED's are often soldered);
- Industrial equipment may not even have a DC line! -- this means you have to rectify the AC for every LED;
When these aspects are considered, it should make it easier to see why a good chunk of (especially older) industrial-grade equipment would prefer neons to LED's. Especially when considering that if a neon "dies", it's often just extremely dim (vs. completely off as an LED typically is) so it still has minimal functionality.
As an example and anecdote, when I was building the glass manufacturing machines, one feature our machines had was that when plugged in, there was an indicator system that told you if the 480V outlet you plugged into was wired properly. It was extremely cheap to build with Neon's (a few lights and resistors), but would have been slightly more costly (and complex) to build with LED's. (Sure, considering the cost of the machine it was barely noticeable so who cares, but we had no reason to use LED's there and this system has been used by the company for decades, so why spend extra time and money designing a new one?)
Source: I used to maintain and build industrial machinery for a plastic injection molding facility, and a glass machine manufacturing facility.
answered Sep 18 at 21:54
410_Gone410_Gone
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Several answers have already discussed the technical reasons, but they don't discuss the applications where those reasons would apply.
A lot of times, you'll see Neon indicators in industrial-grade machinery, for three reasons, two already mentioned:
- Cheaper / easier to drive directly from main voltage (this is important as main voltage rises, like 480V 3-phase systems);
- When under-driven, lifetime is extended substantially;
Simpler installation and circuitry (you can run neons directly off 480V / 277V AC with proper resistors);
As a result, industrial applications using these higher-voltages (note that ANSI still considers 480V a "low-voltage") can save power and cost with appropriately sized neon's. (Sure, it's minimal savings, but typically you need a reason to change something, not keep it the same.)
There are some other curious aspects of industrial systems that generally hold true as well:
- A lot of the logic is 24V DC or 24V AC using relays instead of transistors, easy to drop neons right in;
- The logic often activates raw 480V AC (or 277V AC) equipment -- again, easy to drop a neon in;
- Safety is always a critical issue, because these are often large, dangerous pieces of equipment, so if the bulb dies there should be a possible backup -- once again trivial with neons;
- Industrial equipment is generally expected to take a less-skilled person to service it than smaller electronics (like computers, etc.) -- neons have very common hot-swap plugs on them (LED's are often soldered);
- Industrial equipment may not even have a DC line! -- this means you have to rectify the AC for every LED;
When these aspects are considered, it should make it easier to see why a good chunk of (especially older) industrial-grade equipment would prefer neons to LED's. Especially when considering that if a neon "dies", it's often just extremely dim (vs. completely off as an LED typically is) so it still has minimal functionality.
As an example and anecdote, when I was building the glass manufacturing machines, one feature our machines had was that when plugged in, there was an indicator system that told you if the 480V outlet you plugged into was wired properly. It was extremely cheap to build with Neon's (a few lights and resistors), but would have been slightly more costly (and complex) to build with LED's. (Sure, considering the cost of the machine it was barely noticeable so who cares, but we had no reason to use LED's there and this system has been used by the company for decades, so why spend extra time and money designing a new one?)
Source: I used to maintain and build industrial machinery for a plastic injection molding facility, and a glass machine manufacturing facility.
answered Sep 18 at 21:54
410_Gone410_Gone
2731 silver badge12 bronze badges
$endgroup$
Several answers have already discussed the technical reasons, but they don't discuss the applications where those reasons would apply.
A lot of times, you'll see Neon indicators in industrial-grade machinery, for three reasons, two already mentioned:
- Cheaper / easier to drive directly from main voltage (this is important as main voltage rises, like 480V 3-phase systems);
- When under-driven, lifetime is extended substantially;
Simpler installation and circuitry (you can run neons directly off 480V / 277V AC with proper resistors);
As a result, industrial applications using these higher-voltages (note that ANSI still considers 480V a "low-voltage") can save power and cost with appropriately sized neon's. (Sure, it's minimal savings, but typically you need a reason to change something, not keep it the same.)
There are some other curious aspects of industrial systems that generally hold true as well:
- A lot of the logic is 24V DC or 24V AC using relays instead of transistors, easy to drop neons right in;
- The logic often activates raw 480V AC (or 277V AC) equipment -- again, easy to drop a neon in;
- Safety is always a critical issue, because these are often large, dangerous pieces of equipment, so if the bulb dies there should be a possible backup -- once again trivial with neons;
- Industrial equipment is generally expected to take a less-skilled person to service it than smaller electronics (like computers, etc.) -- neons have very common hot-swap plugs on them (LED's are often soldered);
- Industrial equipment may not even have a DC line! -- this means you have to rectify the AC for every LED;
When these aspects are considered, it should make it easier to see why a good chunk of (especially older) industrial-grade equipment would prefer neons to LED's. Especially when considering that if a neon "dies", it's often just extremely dim (vs. completely off as an LED typically is) so it still has minimal functionality.
As an example and anecdote, when I was building the glass manufacturing machines, one feature our machines had was that when plugged in, there was an indicator system that told you if the 480V outlet you plugged into was wired properly. It was extremely cheap to build with Neon's (a few lights and resistors), but would have been slightly more costly (and complex) to build with LED's. (Sure, considering the cost of the machine it was barely noticeable so who cares, but we had no reason to use LED's there and this system has been used by the company for decades, so why spend extra time and money designing a new one?)
Source: I used to maintain and build industrial machinery for a plastic injection molding facility, and a glass machine manufacturing facility.
answered Sep 18 at 21:54
410_Gone410_Gone
2731 silver badge12 bronze badges
answered Sep 18 at 21:54
410_Gone410_Gone
2731 silver badge12 bronze badges
answered Sep 18 at 21:54
410_Gone410_Gone
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answered Sep 18 at 21:54
410_Gone410_Gone
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I remember using neon indicator lights as crude, inaccurate, but simple voltage references.
The reality is that in today's electronics there are not the voltages present for neon operation. And there are for LEDs.
answered Sep 18 at 13:26
mongomongo
1393 bronze badges
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I agree with you for today's consumer electronics. Industrial electronics often have to sense and/or be powered by a wide range of standard voltages, so voltages that will light up neons in these applications are more accessible.
$endgroup$
– schadjo
Sep 18 at 14:15
$begingroup$
A mobile phone, maybe, yes. But in the home there's always mains voltage. Actually I'd quite like a phone with neon indicators on it. You could do it with a boost convertor. I wonder if we could troll Apple into adding them to Iphones? Hipsters love all that retro shit. I mean, so do I, but for better, deeper reasons! And I started it before they did!
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– Greenaum
Sep 19 at 5:05
add a comment
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I remember using neon indicator lights as crude, inaccurate, but simple voltage references.
The reality is that in today's electronics there are not the voltages present for neon operation. And there are for LEDs.
answered Sep 18 at 13:26
mongomongo
1393 bronze badges
$endgroup$
$begingroup$
I agree with you for today's consumer electronics. Industrial electronics often have to sense and/or be powered by a wide range of standard voltages, so voltages that will light up neons in these applications are more accessible.
$endgroup$
– schadjo
Sep 18 at 14:15
$begingroup$
A mobile phone, maybe, yes. But in the home there's always mains voltage. Actually I'd quite like a phone with neon indicators on it. You could do it with a boost convertor. I wonder if we could troll Apple into adding them to Iphones? Hipsters love all that retro shit. I mean, so do I, but for better, deeper reasons! And I started it before they did!
$endgroup$
– Greenaum
Sep 19 at 5:05
add a comment
|
$begingroup$
I remember using neon indicator lights as crude, inaccurate, but simple voltage references.
The reality is that in today's electronics there are not the voltages present for neon operation. And there are for LEDs.
answered Sep 18 at 13:26
mongomongo
1393 bronze badges
$endgroup$
I remember using neon indicator lights as crude, inaccurate, but simple voltage references.
The reality is that in today's electronics there are not the voltages present for neon operation. And there are for LEDs.
answered Sep 18 at 13:26
mongomongo
1393 bronze badges
answered Sep 18 at 13:26
mongomongo
1393 bronze badges
answered Sep 18 at 13:26
mongomongo
1393 bronze badges
answered Sep 18 at 13:26
mongomongo
1393 bronze badges
1393 bronze badges
$begingroup$
I agree with you for today's consumer electronics. Industrial electronics often have to sense and/or be powered by a wide range of standard voltages, so voltages that will light up neons in these applications are more accessible.
$endgroup$
– schadjo
Sep 18 at 14:15
$begingroup$
A mobile phone, maybe, yes. But in the home there's always mains voltage. Actually I'd quite like a phone with neon indicators on it. You could do it with a boost convertor. I wonder if we could troll Apple into adding them to Iphones? Hipsters love all that retro shit. I mean, so do I, but for better, deeper reasons! And I started it before they did!
$endgroup$
– Greenaum
Sep 19 at 5:05
add a comment
|
$begingroup$
I agree with you for today's consumer electronics. Industrial electronics often have to sense and/or be powered by a wide range of standard voltages, so voltages that will light up neons in these applications are more accessible.
$endgroup$
– schadjo
Sep 18 at 14:15
$begingroup$
A mobile phone, maybe, yes. But in the home there's always mains voltage. Actually I'd quite like a phone with neon indicators on it. You could do it with a boost convertor. I wonder if we could troll Apple into adding them to Iphones? Hipsters love all that retro shit. I mean, so do I, but for better, deeper reasons! And I started it before they did!
$endgroup$
– Greenaum
Sep 19 at 5:05
$begingroup$
I agree with you for today's consumer electronics. Industrial electronics often have to sense and/or be powered by a wide range of standard voltages, so voltages that will light up neons in these applications are more accessible.
$endgroup$
– schadjo
Sep 18 at 14:15
$begingroup$
I agree with you for today's consumer electronics. Industrial electronics often have to sense and/or be powered by a wide range of standard voltages, so voltages that will light up neons in these applications are more accessible.
$endgroup$
– schadjo
Sep 18 at 14:15
$begingroup$
A mobile phone, maybe, yes. But in the home there's always mains voltage. Actually I'd quite like a phone with neon indicators on it. You could do it with a boost convertor. I wonder if we could troll Apple into adding them to Iphones? Hipsters love all that retro shit. I mean, so do I, but for better, deeper reasons! And I started it before they did!
$endgroup$
– Greenaum
Sep 19 at 5:05
$begingroup$
A mobile phone, maybe, yes. But in the home there's always mains voltage. Actually I'd quite like a phone with neon indicators on it. You could do it with a boost convertor. I wonder if we could troll Apple into adding them to Iphones? Hipsters love all that retro shit. I mean, so do I, but for better, deeper reasons! And I started it before they did!
$endgroup$
– Greenaum
Sep 19 at 5:05
add a comment
|
$begingroup$
This is a very niche use, but some neon lamps can be used as logic elements due to the voltage difference in the striking vs maintaining voltages.
You can read about somebody using this, rather than a microcontroller, to control a clock:
- http://www.pa3fwm.nl/projects/neonclock/
- https://hackaday.com/2014/09/29/a-nixie-clock-with-neon-bulb-logic/
answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
1033 bronze badges
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add a comment
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$begingroup$
This is a very niche use, but some neon lamps can be used as logic elements due to the voltage difference in the striking vs maintaining voltages.
You can read about somebody using this, rather than a microcontroller, to control a clock:
- http://www.pa3fwm.nl/projects/neonclock/
- https://hackaday.com/2014/09/29/a-nixie-clock-with-neon-bulb-logic/
answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
1033 bronze badges
$endgroup$
add a comment
|
$begingroup$
This is a very niche use, but some neon lamps can be used as logic elements due to the voltage difference in the striking vs maintaining voltages.
You can read about somebody using this, rather than a microcontroller, to control a clock:
- http://www.pa3fwm.nl/projects/neonclock/
- https://hackaday.com/2014/09/29/a-nixie-clock-with-neon-bulb-logic/
answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
1033 bronze badges
$endgroup$
This is a very niche use, but some neon lamps can be used as logic elements due to the voltage difference in the striking vs maintaining voltages.
You can read about somebody using this, rather than a microcontroller, to control a clock:
- http://www.pa3fwm.nl/projects/neonclock/
- https://hackaday.com/2014/09/29/a-nixie-clock-with-neon-bulb-logic/
answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
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answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
1033 bronze badges
answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
1033 bronze badges
answered Sep 20 at 16:30
zwiebelspaetzlezwiebelspaetzle
1033 bronze badges
1033 bronze badges
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10
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Electricians screwdrivers.
$endgroup$
– Andy aka
Sep 17 at 12:44
1
$begingroup$
I've seen them used as voltage regulators, though mostly in very old circuit designs.
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– Hearth
Sep 17 at 13:43
1
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When the neon lamp does more than just indicate in an old design it is sometimes wise to replace with a neon. For new designs it is rare that a neon is essential though they are robust. They do wear out though if always illuminated.
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– KalleMP
Sep 18 at 8:53
8
$begingroup$
Luminous efficacy isn't an unambiguous virtue. I have tons of electronic crap that annoys me with its bright LED lights that I don't want to see at night.
$endgroup$
– chrylis -on strike-
Sep 18 at 10:38
7
$begingroup$
Neon lamps are were also used as voltage limiters, surge arrestors, sawtooth oscillators and coarse voltage references...
$endgroup$
– rackandboneman
Sep 18 at 11:40