Talk:Dynatron oscillator

Is this really only a tetrode phenomenon? I've seen evidence of a poorly defined parasitic VHF oscillation in a 3CX3000 triode under the grid>anode condition. Sadly the circumstances were not properly documented and never published as we were far more concerned with making it stop than with studying it. 212.159.121.228 (talk) 10:55, 14 March 2011 (UTC)

Parasitic oscillation does not usually result from a negative resistance in the active device. Parasitic oscillations often arise because the circuit is such that the necessary feedback occurs to the active device. A common source of such oscillation is when some device such as a transistor is replaced with a more modern device. The more modern device, although similar in most of its characteristics, has a much higher transistion frequency. The circuit may well provide a positive feedback at frequencies withing the amplifying range of the new device, but were not discovered at the design stage because the original device had no gain at these frequencies. 109.145.22.224 (talk) 16:04, 12 April 2012 (UTC)

Rewrite

Completely rewrote article and expanded it to include the related negative transconductance oscillators like the transitron oscillator. These are very similar vacuum tube negative resistance oscillators which replaced the dynatron after WW2. Removed the "citation needed" hatnote. --Chetvorno^TALK 21:40, 21 March 2015 (UTC)