Make nixie clock dimmer?
August 6, 2023 8:19 AM Subscribe
Can I make a nixie clock dimmer without modifying the circuits? Maybe use a power supply that's rated lower, or something?
I bought a barebones nixie clock off Etsy to use as a bedside clock, but my wife finds its warm, orange glow just a bit too bright at night. It came with a 12V/1A power supply.
Short of soldering, is there any way to make this thing less bright?
And if I can't do it electronically, what would you suggest to visually dim it: put it behind brown glass or vellum or something?
I bought a barebones nixie clock off Etsy to use as a bedside clock, but my wife finds its warm, orange glow just a bit too bright at night. It came with a 12V/1A power supply.
Short of soldering, is there any way to make this thing less bright?
And if I can't do it electronically, what would you suggest to visually dim it: put it behind brown glass or vellum or something?
Second the above. I think brown or amber glass could look amazing, it's possible you could frost the glass of the tubes also/otherwise.
posted by Iteki at 8:44 AM on August 6, 2023
posted by Iteki at 8:44 AM on August 6, 2023
Best answer: Nixie tubes take a couple of hundred volts to light up. The circuit board for your clock will include a boost converter which generates the tube voltage from the 12V input.
It's possible that this circuit is implemented as a simple multiplier of the input voltage, in which case using a lower voltage supply (perhaps 9V) might dim the tubes. It's worth a try if you have a lower voltage supply to hand.
However, I think it's a lot more likely that the boost converter will use an independent bandgap reference, because that's just by far the more common way to do things these days. In that case, reducing the input supply would just leave the brightness constant until eventually the input gets too low to work and it turns off completely.
Modifying it to reduce the brightness would probably be just a matter of replacing a single resistor, but since you've said that's out of scope for you, putting it behind some tinted glass or acrylic sheet is probably the best plan.
posted by automatronic at 9:06 AM on August 6, 2023 [1 favorite]
It's possible that this circuit is implemented as a simple multiplier of the input voltage, in which case using a lower voltage supply (perhaps 9V) might dim the tubes. It's worth a try if you have a lower voltage supply to hand.
However, I think it's a lot more likely that the boost converter will use an independent bandgap reference, because that's just by far the more common way to do things these days. In that case, reducing the input supply would just leave the brightness constant until eventually the input gets too low to work and it turns off completely.
Modifying it to reduce the brightness would probably be just a matter of replacing a single resistor, but since you've said that's out of scope for you, putting it behind some tinted glass or acrylic sheet is probably the best plan.
posted by automatronic at 9:06 AM on August 6, 2023 [1 favorite]
Best answer: Can I make a nixie clock dimmer without modifying the circuits?
There's a remote chance the high voltage circuit (90..150V depending on the tubes used) that powers the nixies contains a variable resistor, a component that looks like one of these, but a) it would raise the cost of the circuit by a dime or two, and b) people will start fiddling with it and likely keep it at a higher voltage for more brightness but damaging the tubes. So nearly all builders would set the circuit at a fixed voltage.
Some tinted sheet in front would be the most practical way.
posted by Stoneshop at 10:16 AM on August 6, 2023 [1 favorite]
There's a remote chance the high voltage circuit (90..150V depending on the tubes used) that powers the nixies contains a variable resistor, a component that looks like one of these, but a) it would raise the cost of the circuit by a dime or two, and b) people will start fiddling with it and likely keep it at a higher voltage for more brightness but damaging the tubes. So nearly all builders would set the circuit at a fixed voltage.
Some tinted sheet in front would be the most practical way.
posted by Stoneshop at 10:16 AM on August 6, 2023 [1 favorite]
Best answer: Two pieces of polaroized film , rotate one to achieve the dim.
posted by hortense at 10:34 AM on August 6, 2023 [1 favorite]
posted by hortense at 10:34 AM on August 6, 2023 [1 favorite]
Best answer: Neutral Density would be the filter you want if you go that way. (Just an example not an endorsement)
posted by Uncle at 11:19 AM on August 6, 2023
posted by Uncle at 11:19 AM on August 6, 2023
Response by poster: Update: vellum makes it an illegible smear.
Window-tinting mirror film is the next thing I could find on the basement to try.
Where can someone buy a small (maybe 75mm x 30mm) piece of amber glass, anyway?
posted by wenestvedt at 11:30 AM on August 6, 2023
Window-tinting mirror film is the next thing I could find on the basement to try.
Where can someone buy a small (maybe 75mm x 30mm) piece of amber glass, anyway?
posted by wenestvedt at 11:30 AM on August 6, 2023
Best answer: I have a clock radio that was too bright. I went to the office supply store, found some tinted plastic sheets, and cut those up and layered them over the display until it was dim enough. Look in the presentation folder / folio section -- you just want neutral gray but still transparent.
It's amazing how sensitive you become to stray light once your eyes adapt. You may have to dim it all the way down to "can't read it during the day" to make it acceptable for nighttime.
posted by intermod at 9:21 PM on August 6, 2023
It's amazing how sensitive you become to stray light once your eyes adapt. You may have to dim it all the way down to "can't read it during the day" to make it acceptable for nighttime.
posted by intermod at 9:21 PM on August 6, 2023
> Where can someone buy a small (maybe 75mm x 30mm) piece of amber glass, anyway?
Search for "Perspex Amber 300" and look for a supplier near you selling it in custom sizes.
posted by automatronic at 2:02 AM on August 7, 2023
Search for "Perspex Amber 300" and look for a supplier near you selling it in custom sizes.
posted by automatronic at 2:02 AM on August 7, 2023
Response by poster: Solution: I used two layers of window-tinting film, folded neatly around the clock's case, and now my wife doesn't even notice the light. I tried just one, but it wasn't enough.
Thanks, everyone!
posted by wenestvedt at 11:05 AM on August 14, 2023
Thanks, everyone!
posted by wenestvedt at 11:05 AM on August 14, 2023
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posted by Larry David Syndrome at 8:33 AM on August 6, 2023 [1 favorite]