On Thursday, July 6, 2017 at 3:19:34 AM UTC-4, frank wrote:
Phil Hobbs wrote:


Maybe Barkhausen oscillation (aka the Barkhausen-Kurtz effect). This
used to show up in old-fashioned incandescent light bulbs that were
evacuated instead of argon-filled.

according to a wikipedia article, the Barkhausen-Kurz oscillator used
triodes. So I'm still puzzled.
I'll try to make a test setup with constant current on a GDT and try
to measure the frequency of the oscillation.

Frank

Not knowing Barkhausen-Kurz from Berkinstocks, I think Phil means it
has to do with the time delay. Enough gain and a time delay leads to
oscillations. (hmm just like in thermal control loops.)

George H.