Vacuum Tube Clock

[alfa88]

1st off I tried searching the forum but it didn't seem to work. I tried a google search and found plenty of Nixie clocks. Nixies are not vacuum tubes! Anyhow, I was contemplating maybe building a Nixie clock but instead of ICs or even discrete transistors using vacuum tubes. Has anyone ever attempted this or have some info?

 

[crutschow]

Has anyone ever attempted this or have some info?

You might look at this, discussing the operation of a HP tube decade counter.
Also look at the Dekatron tube.

 

[AnalogKid]

You can get one binary flipflop out of a dual triode. A four digit (hours and minutes) clock needs a minimum of 13 flipflops, plus more tubes for carry-gating, plus more tubes for some kind of time-setting capability, plus more tubes for display decoding.

People have built digital clocks using nothing but opamps (no digital IC's) and nothing but transistors (no IC's or any kind), so I wouldn't be surprised if someone already has done this with jars.

ak

 

[alfa88]

You might look at this, discussing the operation of a HP tube decade counter.
Also look at the Dekatron tube.

Thanks. Sure enough the next day I jumbled the search terms around and found a few results.
http://www.jogis-roehrenbude.de/Leserbriefe/Bruegmann-Digital-Roehren-Clock/Digital-Roehrenuhr.htm
Yikes!
and a Dekatron approach from our friends at Hackaday:
https://hackaday.com/2014/07/22/cold-war-clock-is-all-tubes/

Definitely not for the faint-hearted

 

[alfa88]

I ordered up some Dekatrons but I don't know how successful I'll be as they're coming from Ukraine. Making one flip flop from vacuum tubes is one thing but an entire clock string is way out of my budget.