On Tue, 26 Sep 2000 08:26:22 -0400, Tom Rauch wrote:
>The correct and reliable way to add negative feedback in a
>multiband grounded grid triode PA, especially one with grid current,
> is to add a resistance right at the cathode.
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Is a resistor in the cathode true negative feedback? Sounds more like
a gain reduction/stability method to me. Putting a resistor in the
cathode circuit no doubt adds some stability by lowering the Q of the
circuit. True negative feedback requires taking part of the output
signal and feeding it back out of phase to the input.
I'm not saying the resistor isn't advantageous, just that it isn't
really negative feedback. Comments?
73, Bill W7TI
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