How to Extend the Lifespan of IN-14 Nixie Tubes?

[Christoph Brandstätter]

Hi everyone,

I recently acquired six IN-14 Nixie tubes and plan to build a clock with them. Ideally, I’d love to keep the clock running 24/7, but I’m concerned about how this might affect their lifespan. I’m aware of issues like cathode poisoning, so I know it's important to regularly cycle through all digits to prevent buildup. However, I’d like to know if there are other best practices or tips to ensure they last as long as possible.

Here are some specific questions I have:

1. Lifespan in Continuous Operation: I know that running Nixie tubes 24/7 reduces their lifespan, but does anyone have experience with how long they actually last under continuous use?

2. Lower Current: Does running the tubes at a lower current significantly extend their life? What current settings have worked well for others?

3. Multiplexing: Is multiplexing a good approach for improving lifespan, or is it better avoided?

4. Presence Sensors: I've seen people use presence sensors to only light up the tubes when someone is nearby. If anyone has implemented this, what hardware or sensor type do you recommend?

I’d also appreciate any other tips or experiences you might have regarding maintaining the longevity of Nixie tubes.

Looking forward to learning from you all!

[Senk Ju]

I have had an IN-14 clock running 16h/day for around five years and the tubes still look as good as the day I got them. I also know people who have had their IN-14 clocks running for decades without any noticeable degradation of the tubes. It’s generally advised to drive Nixie tubes at their rated current, as running them at too low a current can increase the risk of cathode poisoning. If you’re multiplexing the tubes, keep in mind they’ll need higher currents to achieve the same brightness since each tube is only illuminated for a fraction of the time (e.g., 1/6 if six tubes are multiplexed). For a clock, however, dimmer tubes might actually be desirable. Whether multiplexing is good or bad for the tubes seems to be a topic of debate. I don't think you have to worry about it damaging the tubes. If you are concerned with longevity, I would instead recommend turning off the tubes at night. 

[Richard Scales]

For my designs, a motion sensor (usually mounted remotely) is a must have for any design that uses expensive tubes so they are on only for a limited time. You wouldn't leave all the lights on in a room if you were not using it would you ?
I have used PIR modules as well as microwave sensors. PIR I usually mount remotely and plug in with a cable - a microwave type sensor can easily be built in to the housing of a lot of clocks.
For PIR I have used HC-SR501 and HC-SR505. For microwave sensors I have used several including RCWL0516. The microwave sensors are more sensitive and can 'see through walls'!
- Richard

[Christoph Brandstätter]

Thank you both for your helpful insights! I really appreciate the detailed advice.

Regarding the motion sensor, I do see how it could be a great solution to prolong the tubes' lifespan. However, I have two cats, and I’m concerned they might trigger the sensor frequently, which would defeat the purpose. That said, the clock will be placed inside a display case, so the cats won’t have direct access to it.

I’ll keep thinking about the motion sensor idea and see if I can make it work despite the cats. Thanks again for sharing your experiences and recommendations – they’ve been very helpful!

[Terry S]

I've used these motion sensors from Panasonic:

 https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/2240/EKMB_MC_AMN2_3_Rev_Sep_2012.pdf

Super easy to use. Seems they've gotten a bit pricey since I used them last. The one I used is AMN31111.

[Leroy Jones]

Put a toggle switch on the front of the clock.   Turn the tubes off when you leave the room.

Turn them on when you want to see them.   All of my nixie clocks have it.

[Martin Niec]

That is some seriously looking piece of gear. What is the numerical keyboard for and how do you operate it?

[Moses]

I believe you can tune some of the microwave (and maybe some of the PIR?) to basically ignore small pets. I don't have too much direct experience, but there is info all over the web about microwave / MMwave stuff.

On a tube lifetime note, I just realized the first serial number of the first 6 digit clock kit I made in 2005 has been continuously running since! Z57xM tubes with 175,000+ hours! I see no degradation at all!

-Moses

[ZY]

I'm not sure about cats but I also use the Panasonic PIR sensors for my IN-18 build, they are nice because they are black colored so it doesn't stick out like a white PIR sensor does. I use EKMC7607112K, of which there's a Sparkfun breakout board for.

That being said, I have a IN-14 clock running continuously 24/7 for over 7 years without any special cycling algorithm and so far all the numbers still look ok. I haven't checked the unlit digits though. For my IN-18 clock, on every digit change I have it cycle through all the unlit digits, so it has that 3D animation effect, but maybe it'll also clean the cathodes. 

My concern with my IN-18 clock is that maybe a PIR turning them on and off can also cause some sort of damage through thermal cycling. Perhaps the ultimate overkill method would be to keep the tubes enclosed and have a heater running 24/7 so when they do turn on from the PIR there's no thermal shock, haha.

[padler...@gmail.com]

Is there a trick to getting the RCWL-0516 microwave sensors to work?  I’ve tried using it on one of my clocks with no success. Either the module continuously false triggers so that the display never blanks, or if the display does finally blank, it only responds to motion literally 1 or 2 cm in front of it. Either way it’s useless! I bought a batch of 10 and have tried four of them so far with the same results. I thought perhaps the first one I tried might have been defective, but I’m reluctant to believe all four that I’ve tried so far are.  I see many similar comments online, but then again I see some that say it works like magic.  Is there a trick to getting them to work?

Randy

On Jan 27, 2025, at 3:57 AM, ZY <zongy...@gmail.com> wrote:

I'm not sure about cats but I also use the Panasonic PIR sensors for my IN-18 build, they are nice because they are black colored so it doesn't stick out like a white PIR sensor does. I use EKMC7607112K, of which there's a Sparkfun breakout board for.

--
You received this message because you are subscribed to the Google Groups "neonixie-l" group.
To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+...@googlegroups.com.
To view this discussion, visit https://groups.google.com/d/msgid/neonixie-l/9a628b96-4175-45e6-8344-fc1801a8aa35n%40googlegroups.com.

[Christoph Brandstätter]

Thank you all for your help and input. Based on the information shared in the group, running the IN-14 Nixie Tubes 24/7 seems like a straightforward and practical approach. Adding sensors could introduce potential issues, and I personally prefer the look of the tubes when they run continuously. Since the long-term lifespan appears to be sufficient based on shared experiences, this works perfectly for me.

Once again, thank you all for your support!