Posted by PakProtector [ 64.12.116.65 ] on December 07, 2005 at 17:31:02:

In Reply to: Re: I think I can guess the origin of that quote.... posted by Damir on December 05, 2005 at 12:50:51:

Keep one thing in mind, oscillation is *NOT* a class A affair. It runs to extremes, usually to grid current...

If you have the grid of any stage running to positive values, the sonics are going to suffer for some non-zero recovery period. This period will be longer than the one oscillation, and is one mechanism by which a 22 MHz oscillation can make itself known.

I tried a high gm cascode and found it singing along with 20V peak-peak of 22 MHz oscillation. Resistive dampers cured it, and the circuit souded better. No easy way to be sure you've got things under control save to measure carefully.
cheers,
Douglas

and speaking of high gm, how 'bout a 100,000 mA/V device?

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