IN-14 nixie tube clock

[niekproductions]

I'm simply fascinated by the look of nixie tubes. After doing some research, I drew up this schematic and ordered the necessary parts.
I haven't had time to draw the power supply, but I've already got it working on a breadboard. I'm posting this to see what you think.
For driving the nixies, I'm using the ancient 74141 IC. They're controlled by some standard shift registers.
The time is kept by a DS1307. Since I like my bedroom completely dark when I switch off the lights, I've included a photoresistor to dim the clock. For future purposes, I've also added a 38kHz IR receiver.



Now in all of my research online, I haven't been able to find what anode resistors to use for my tubes. The datasheet states the firing voltage as 170 volts, but it doesn't say anything about the maintaining voltage. The digit current should be between 2-3.5mA and the for the decimal points 0.3-0.7mA. 

[niekproductions]

I received my six nixies from Ukrain yesterday. Eager to test them out, I assembled the 12-180V power supply and calculated the anode resistors. I'm driving the numbers at 135V/2,3mA and the decimal points at 136V/0,32mA.

Luckily, the tubes all worked! Some of them were missing the leg for the left decimal point, but I wasn't using that anyways 

[niekproductions]

I ordered PCB for the top part (nixies, 74141's and MPSA42's) from Jaco HK.


After about 14 days, they arrived in a nice box, with lots of antistatic bubble wrap.





I have to say I'm very impressed with the price/quality ratio. They also arrived very soon

[MrAureliusR]

Any chance you've got an extra one of those boards you could sell? PM me if you can

Also -- beautiful work! I'm just re-discovering Nixies and accidentally ordered IN-15B ones... oops. However they do have, among other symbols, Hz and ? which is cool. I'm getting 12 of them though 

Is the IN-14 a good choice for building a clock? I'm trying to find ones that aren't terribly expensive, even if they're quite small I don't mind, I just want to learn more about driving them. I've noticed there seem to be a few different ICs for driving them, what are the differences? I remember Dave showing a bag of TO-92s from Fran in his recent Mailbag and saying that they were Nixie drivers.

Keep up the awesome work!

[niekproductions]

Any chance you've got an extra one of those boards you could sell? PM me if you can

Also -- beautiful work! I'm just re-discovering Nixies and accidentally ordered IN-15B ones... oops. However they do have, among other symbols, Hz and ? which is cool. I'm getting 12 of them though 

Is the IN-14 a good choice for building a clock? I'm trying to find ones that aren't terribly expensive, even if they're quite small I don't mind, I just want to learn more about driving them. I've noticed there seem to be a few different ICs for driving them, what are the differences? I remember Dave showing a bag of TO-92s from Fran in his recent Mailbag and saying that they were Nixie drivers.

Keep up the awesome work!

I almost made the mistake of purchasing the 15B's too, they're a lot cheaper. I chose to go with IN-14 because they were the cheapest standing ones I could find ($25 for 6). I prefer long ones over the direct mount ones that Fran sent Dave.

My board uses K155ID (russian 74141) drivers. I'm using MPSA42's (the ones Dave got) to drive two decimal points.

I have got a couple of spare boards. I haven't got around to fully testing one though, got it partially assembled now. The long leads sure are a pain to get in the holes though. I'll continue on saturday:

[MrAureliusR]

Oh man I'm so jealous!! Really can't wait to get working with Nixies

[niekproductions]

Oh man I'm so jealous!! Really can't wait to get working with Nixies

I couldn't either, but it's worth it to have a little patience and do some proper research first. Otherwise you might just end up with some IN-15B nixies
I almost sent out the design files with some obvious shorts and even some unrouted traces 

[cwalex]

The long leads sure are a pain to get in the holes though.

To make it easier you can just cut the leads progressively shorter as you go from one lead to the next in a circle. So that one lead is shorter than the previous lead which is shorter than the previous lead etc. This way you can get each lead in the hole you want it in without the other leads getting in the way. Hope that makes sense.

[c4757p]

I use these tweezers for manipulating pretty much any small parts when assembling electronics. I've used them before to install a VFD in a similar form factor to that Nixie, but half the size and with twice as many pins, and they worked very well for that (as they do for everything else). It's very easy and graceful to grab each wire with them and guide it into place. They're small enough to weave in and out of the other wires and strong enough that they don't slip.

They can even be poked into molten solder, as it doesn't stick to the stainless steel.

[VEGETA]

where to buy these nixies? << I am from middle east.

And, is there any other color to pick?

[niekproductions]

The long leads sure are a pain to get in the holes though.

To make it easier you can just cut the leads progressively shorter as you go from one lead to the next in a circle. So that one lead is shorter than the previous lead which is shorter than the previous lead etc. This way you can get each lead in the hole you want it in without the other leads getting in the way. Hope that makes sense.

That's an excellent tip, thanks!

where to buy these nixies? << I am from middle east.

And, is there any other color to pick?

I got mine from ebay. You should be able to get six of them for about $30.

Nixies get their colour from the neon gas inside. I believe there are some nixies with another type of gas that glows in a different colour, but they're terribly expensive.