I've got a question.
A few years ago I built a neon flower which is a few neon lamps in parallel and a cap and resistor. Operates off AC and the neons randomly flicker.
Wanted something else and found a neon ring counter so I expanded that to 10 neons.
Here's a video of both in operation
Later on I thought why not build one 12 neon ring counter, two 10 neon ring counters and two 6 neon ring counters and arrange the neons in a circle with numbers by each neon. I'd then add a divide by 10 and divide by 6 so that I get a 1PPS signal. I'd add three pushbutton switches so that I can set each digit individually to the time.
Based on the operation of the ring counter how it isn't always 100% perfect, I know a clock would require carefully selected and aged neons.
Also the clock would need to run 24/7 or I'd have to reset it every time
Would this even be worth doing?
If not what are some other neon lamp circuits I could build?
A few years ago I built a neon flower which is a few neon lamps in parallel and a cap and resistor. Operates off AC and the neons randomly flicker.
Wanted something else and found a neon ring counter so I expanded that to 10 neons.
Here's a video of both in operation
Later on I thought why not build one 12 neon ring counter, two 10 neon ring counters and two 6 neon ring counters and arrange the neons in a circle with numbers by each neon. I'd then add a divide by 10 and divide by 6 so that I get a 1PPS signal. I'd add three pushbutton switches so that I can set each digit individually to the time.
Based on the operation of the ring counter how it isn't always 100% perfect, I know a clock would require carefully selected and aged neons.
Also the clock would need to run 24/7 or I'd have to reset it every time
Would this even be worth doing?
If not what are some other neon lamp circuits I could build?
I'll look at that tomorrow. Thanks for posting it.
Now for the divide by 10 and 6 I'd use two dekatrons.
Oh I also have a dekatron spinner I added variable speed to using a neon lamp to discharge a capacitor into a transistor with a variable resistor controlling the charge time of the cap. Of course I'm limited by how fast the neon can flash before it is steadily lit, however the dekatron spinner is going quite fast by then.
Now for the divide by 10 and 6 I'd use two dekatrons.
Oh I also have a dekatron spinner I added variable speed to using a neon lamp to discharge a capacitor into a transistor with a variable resistor controlling the charge time of the cap. Of course I'm limited by how fast the neon can flash before it is steadily lit, however the dekatron spinner is going quite fast by then.
Yes, if you find it fun to do or if you need a clock.
Some glow discharge tubes from 50+ years ago only have a small part of their radioactive primer left, depending on the half-life of the primer. Some tubes have an extra anode as primer, those are not affected at all. If the work function of the cathode is low enough, light can also be an effective primer.
If you ever happen to be in England, visit the National Museum of Computing to see the WITCH, a dekatron-based computer. https://www.tnmoc.org/first-generation-gallery
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It would be nice to have a clock and would be quite the conversation piece, however I don't know how long the neons would last being run 24/7. I would want something that would last several years.
Now it is possible to use a circuit and some 74141 or Russian equivalent chips to drive the neons and use a switch to turn the neons off, but that defeats the purpose.
If it was as simple as using pretty much any currently available neon bulb and knowing it would work 100% without fail, then I'd definitely build the clock, however I know to get something as close to 100% working without fail as reasonably possible will take buying many neons and selecting them based on specs then aging them or finding someone who offers that service and pay for it.
It's one thing to have a neon ring counter driven by a 1 transistor neon lamp oscillator miss a neon every now and then or randomly restart at the first neon as it doesn't matter, but to have a ring counter in a clock do that does matter.
Another option is to use all dekatrons for the clock, but that would be quite boring.
That said what other circuits are out there that use neons?
The circuit that flashes two neons back and forth is too basic and I already have a neon flower and ring counter.
I had wanted a circuit that would flash each neon in a row of neons going right then left and repeat it, but I don't see a way to do that without active electronics and I'm trying to stay with a minimum of active devices aside from something such as a transistor used with a neon to produce a pulse oscillator to drive a passive neon circuit.
Now it is possible to use a circuit and some 74141 or Russian equivalent chips to drive the neons and use a switch to turn the neons off, but that defeats the purpose.
If it was as simple as using pretty much any currently available neon bulb and knowing it would work 100% without fail, then I'd definitely build the clock, however I know to get something as close to 100% working without fail as reasonably possible will take buying many neons and selecting them based on specs then aging them or finding someone who offers that service and pay for it.
It's one thing to have a neon ring counter driven by a 1 transistor neon lamp oscillator miss a neon every now and then or randomly restart at the first neon as it doesn't matter, but to have a ring counter in a clock do that does matter.
Another option is to use all dekatrons for the clock, but that would be quite boring.
That said what other circuits are out there that use neons?
The circuit that flashes two neons back and forth is too basic and I already have a neon flower and ring counter.
I had wanted a circuit that would flash each neon in a row of neons going right then left and repeat it, but I don't see a way to do that without active electronics and I'm trying to stay with a minimum of active devices aside from something such as a transistor used with a neon to produce a pulse oscillator to drive a passive neon circuit.
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The WITCH is dekatron-based for reasons of reliability and lifetime, so apparently glow discharge tubes can work reliably for a long time. It's probably a good idea to keep the currents through the neon lamps well below their maximum ratings.
Dekatrons are definitely a long life device.
Regular neon bulbs don't seem to always last several decades and their characteristics tend to change some as they age.
Depends on the neon though.
I've seen some small neons used in indicators that plug in a socket not last very long running 24/7 and they used a 33k series resistor for 120V operation failing with the neon blackening. I've solved that by opening some and using a 100k resistor instead which greatly extends their life.
Regular neon bulbs don't seem to always last several decades and their characteristics tend to change some as they age.
Depends on the neon though.
I've seen some small neons used in indicators that plug in a socket not last very long running 24/7 and they used a 33k series resistor for 120V operation failing with the neon blackening. I've solved that by opening some and using a 100k resistor instead which greatly extends their life.
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Looking online there doesn't seem to be many neon lamp circuits other than ring counters which can use a various amount of neons and flashers that can use one or two neons.
Note that it (the WITCH) is only reliable compared to machines using tubes with heaters (and relays or course!), not necessarily that great... IIRC they had it restored at Bletchley Park in the computer museum there.
I suspect you can spot tubes before they fail by visual inspection, which may be a plus.
