[time-nuts] Digital Clock kit - no Integrated circuits!

Bob Camp lists at cq.nu
Sat Jan 9 15:53:08 UTC 2010


Hi

I *think* I still have a case of gas filled dual triodes sitting in the shed. The Beckman EPUT meter used them in the decade divider / display sections. I don't have any of the meters any more, but I do have the spare parts for them. Go figure ....

They actually make pretty good low speed logic gates. 

Tube based clock driving neon bulbs for the display anybody?

Bob


On Jan 9, 2010, at 10:30 AM, Lux, Jim (337C) wrote:

> 
> 
> 
> On 1/9/10 12:09 AM, "Steve Rooke" <sar10538 at gmail.com> wrote:
> 
> 2010/1/9 Tom Clifton <kc0vsj at yahoo.com>:
>> http://transistorclock.com/  has a very interesting (though a bit expensive) kit for sale.  A 10" x 11" circuit board sporting nearly 200 transistors and 600 diodes to drive six seven-segment displays.  Suitable for framing...  As delivered runs on 60hz but there is a note about conversion to 50hz mains.  You can buy a  bare board, just the components or a full kit.
>> 
>> You must see it to believe it!
> 
> Bah humbug! Stupid modern day design, it'll never be any good, you
> need to use valves to make real gear :-)
> 
> Well, they do make dual triodes which are convenient for making those Eccles-Jordan circuits.
> 
> I can't help wondering if you go do better than the 4 bit counter:4-10 decoder:10-7 decoder.  Yeah, simple diode matrices in an AOI configuration are easy, but surely a bit of work (as in digging up archaic designs) could find a "lower part count" approach.  Time to use that Karnaugh map.
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
> 




More information about the time-nuts mailing list