Cory Heisterkamp via cctalk wrote: > > > > On Mar 8, 2026, at 5:18 PM, Holm Tiffe via cctalk <[email protected]> > > wrote: > > > <snip> > > > > ..so I have an working ring counter here next to me on a breadboard. :-) > > > > There is still an MPSA42 used as an pulse former in the clock circuit > > that I want to change agains a trigger tube. I need an Ide of an circuit > > that gets triggered on approx. 30-40V and outputs an rectangle pulse of > > lets say 60V and 10-30µs duration to properly trigger the ring counter, > > using possibly only one trigger tube. > > I think no one knows that for now..but I'm very grateful for links > > to older literature on this topic. > > approximately in 2000 I'm parted out old hp tube counters, the displays > > where "thermometer Displays using 10 pcs. of neon lamps, one for each > > number. The counters used 4 12at7 type "digital" tubes (don't remember > > the exact type for now) with biquinary output to the neon lamps. > > Later hp counter modules used the very same schematics and the neons and > > one hybrid photoresistor module in front of the neons as decoder to > > drive nixie tubes. I've tried it already in the past with the neon bulb > > ring counters.. a cheap photoresistor in a balc schrink tube that was > > put onto the neon lamp can switch a nixie..it works flawlessly. > > Tried this on the TX4b .. works too. :-) > > ..other schematics ad an additional trogger tube for each nixie > > cathode..the effort pretty much explodes... > > > > Hope someone can help with some hints or links. > > > > Regards, > > Holm > > Hello Holm, I very much recall when Friedhelm completed his clock. > Ironically, I was building my own version in parallel initially unaware of > his project. For mine, I used Beckman modules which I modified for proper > roll-over, and drilled out the “thermometer” indicator fronts to mount CdS > cells for the Nixies. The timebase was a dekatron “Phantastron” circuit > operating at 1 PPS. Black crinkle paint and IBM toggles with proper trim nuts > completed the package. A slightly lower power bill, but not by much, haha. > Here’s a 20+ year old photo. > https://linearlook.com/eldocountry/projects/tubeclock/tube1lrg.jpg > > I have considered using neons in a ring circuit for a sequencer in my > home-brew relay computer, but will probably go a different direction. Some > folks have had success, but it requires much binning to get the desired > characteristics for reliable operation. You were curious about links, I > highly recommend this one: > https://www.worldradiohistory.com/Archive-Catalogs/Suppliers/GHI/GE-Glow-lamp-manual-Theory-Circuits-Ratings-2nd-Edition-1965-118-pages.pdf > > Best Regards, > Cory Heisterkamp
Hi Cory, I've even remember to have seen your nice clock in the past! ..and yes, using a decatron for the time base saves much of the divider logic needed otherwise. Many Thanks for the link to the GE neon bulb manual, from the link below (using and understanding..) I'm already know how todo logic elemnts with neon bulbs :-) ..here something with similar content back to you: William G. Miller "using and understanding miniature NEON Lamps": http://www.tiffe.de/roehren/neon.pdf Here a short video from my breadboard ring counter with TX4b: http://www.tiffe.de/roehren/tx4b-ring-counter.mp4 ..and here the russian/english/french Manual for that soviet TX4b Thyratron based Morse sender: https://www.tiffe.de/roehren/R010-morse-TX4B.djvu pollin.de currently sells TX4b for 25 Eurocent/peace at 100 pcs. in case someone is interested in such stuff. I do have large amounts of small chinese Neon Lamps if someone needs them https://www.tiffe.de/roehren/Glimmlampe.jpg Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Goethestrasse 15, 09569 Oederan, USt-Id: DE253710583 [email protected] Tel +49 37292 709778 Mobil: 0172 8790 741
