Nixie tube watch: I need schematics!

[elShoggotho]

The basic plan is to make a nixie tube wristwatch with, and that's important, four digits. Does anyone have schematics for a nixie tube watch small enough by design to fit into a wrist-mounted casing that runs off 1.5 to 3 volts?

[JingleJoe]

30 seconds of googling reveals this

http://www.cathodecorner.com/nixiewatch/firmware/firmware.html

[elShoggotho]

30 seconds of googling reveals this

http://www.cathodecorner.com/nixiewatch/firmware/firmware.html

The basic plan is to make a nixie tube wristwatch with, and that's important, four digits. Does anyone have schematics for a nixie tube watch small enough by design to fit into a wrist-mounted casing that runs off 1.5 to 3 volts?

Highlighted the relevant parts. I should also have added that I don't have the means to program PIC elements. I found that link lacking.

[Endeavour Cull]

You're sounding a bit tyrant in my opinion. I don't think that helps.  

[elShoggotho]

You're sounding a bit tyrant in my opinion. I don't think that helps.  

I should have added the following:
After my google search ran dry regarding the specific design I seek, I come to you, fine ladies and gentlemen, to ask for your help in the acquisition of the following...

But I got lazy.

[Hardwick Steam Impl. Co.]

I think the biggest challenge will be to find ultra-miniature tubes. I've seen only the one design in the above link, and as far as I can tell those tubes are impossible to find.

[Endeavour Cull]

You're sounding a bit tyrant in my opinion. I don't think that helps.  

I should have added the following:
After my google search ran dry regarding the specific design I seek, I come to you, fine ladies and gentlemen, to ask for your help in the acquisition of the following...

But I got lazy.

A bit late, but i forgive you. 

I know you can't program Pic's, but here they speak of "seven segment display's' (leds) that look like the nixies
http://picnote.blogspot.com/2009/04/classic-led-7-segment-displays.html


In relation to a smd chip

datasheet; http://pdf1.alldatasheet.com/datasheet-pdf/view/115496/HP/HP5082-7740.html

There are some already clock pics. : http://www.elettrosurplus.com/sh_index.php?c=89&p=258
Maybe if you find a vintage alarmclock from the seventies there may be one in it.

this whole page is full with alarm clock ic's that are just the thing you seek.


The pictures on this are just for drooling purposes.

[elShoggotho]

Interesting, but seven segments. Not exactly my favourite.

[Endeavour Cull]

Yes i know you rather want the real thing, but when not available this could be a good and workable  alternative.
The ones in the first link have a lens surface (sphere) so they are a bit nixie-like in appearance.

I seriously wonder if there are nixies that opperate at 1.5 to 3 volts.

[arcwelder]

I seriously wonder if there are nixies that opperate at 1.5 to 3 volts.

From what I recall of similar projects, they don't. You step the voltage up to whatever the tube wants to run on. This requires extra circuitry and creates additional problems to solve, but it isn't prohibitive. The result is going to be a bit oversized anyway thanks to the nixies.

It can work, see here and here. You may or may not be able to wheedle schematics out of the designer. Notably, the first link includes a shot of the PCB involved, which should give you a fair amount of information if not necessarily everything you need.

You should also be able to modify the schematics Joe linked to if it comes to that. Two digits or four is relatively meaningless since the timing circuit has to know when to do its thing regardless of how much info is actually displayed. It will also include everything necessary to get the voltage up to operating levels with a wristwatch-scale circuit.

[Mr. Consciousflesh]

The hard part will be getting the nixie tubes that will fit into the watch . I'm building a nixie watch too and I spent almost a year looking for suitable tubes. Recently I bought some Burroughs B5870ST tubes and now I can resume this project .
In my opinion all the schematics I found on the web have one issue which is a serious disadvantage in a wristwatch - they do not use multiplexing . If you look at these projects you will see that all the cathodes of the neon lamps are controlled by separate switches ( usually HV transistors ) . This classic solution seems to be a bit out of place in the watch , since it will consume a lot of space ! In my design I'm planning to use a different approach : only 10 transistors , and a multiplexed HV source for the anodes.  I will post more about this project soon .

[Endeavour Cull]

Is it possible to use some Darlington array, maybe smd type?

Like the ULNxxx
http://www.datasheetcatalog.com/datasheets_pdf/U/L/N/2/ULN2065B.shtml

[markf]

Love the Krusty the clown version. markf
http://www.amug.org/~jthomas/watch.html

[Mr. Consciousflesh]

Is it possible to use some Darlington array, maybe smd type?

Yes , it is possible . You will have to remember to add a Zener diode between the common diode pin and the ground . The darlingtons are rated only for 50 or 80 volts depending of chip , and the ignition voltage of the nixie tube is usually greater than 120V . Without the Zener diode the Darlington array may not last too long .

[Endeavour Cull]

I know ElShoggoto asked for a four digit wristwatch, but for inspiration i'll like to show this one too.



Quote:"A timepiece such as this could make grown geeks cry!"

http://www.synbio.org.uk/component/content/article/46-instrumentation-news/1483-little-nixie-tube-watch.html?directory=257

Here is some more info on nixies and drivers: http://www.decodesystems.com/nixie.html


 Burroughs B4998


Here is one interesting shop: http://www.sphere.bc.ca/test/nixies.html It even got the ic driver somewhere down the page.

http://www.sphere.bc.ca/test/nixies.html#catalog
Look for the IN 17 they got for sale :

[chainmailleman]

I don't think this will be a wrist watch, maybe an alarm clock, but if you feel like lugging around a battery bank I can hook you up with something that might work. It will require some integrated circuits to reduce space taken up. But if you live by a radio shack or fry's it shouldn't be an issue obtaining the materials and tools....except the nixie tubes.