"John T. M. Lyles" wrote:
> Once I spent hours explaining to an experienced RF oscillator
> designer (RF heating business, big oscillators) that RF amplifiers
> can oscillate while also amplifying on the desired frequency. This
> engineer couldn't believe it was possible, and never agreed to the
> possibility. I didn't sweat it, as I had a whole career to learn
> about things like this, with an open mind.
In signal amps, one of the sure signs that a low noise signal amplifier
has out of band oscillation, is a poor noise figure, even if the device
seems to be delivering rated gain. The principle is identical...
Sometimes the "oscillation" is nice and smooth, so that monitoring
voltages and currents might not drop a clue.
Ian ZS6BTE
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