Mixed day. After I blew up my function generator two weeks ago, by applying 300V to its output, today the magic smoke escaped for no reason from my 450V home built power supply. My indestructible 300V Delta Zierikzee power supply unfortunately just doesn't give enough for the Dekatrons to fire up. thankfully I found yet another home grown power supply in the attic, up to 400V.

This helped me to find one problem why the Dekatron wasn't spinning on first try. It appeared that for some reason, a large DC component appeared on the gates of the dekatron, where I would expect only 50 ~ 100V AC, phase shifted between G1 and G2. I still haven't pinpointed the cause, but I solved the problem by adding a 390nF capacitor, blocking whatever DC component there is.

Had it working. Then it stopped working again. This turned out to be a loose solder joint with one of the pins of the dekatron. With that solved, I have a spinner. Next stage is to get the output signal from the spinng dekatron. That should be 10Hz, to be inverted by one of the triodes and fed to the second dekatron, which should churn out the desirable 1Hz.