> Is a resistor in the cathode true negative feedback? Sounds more like a
Of course it is!
> 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.
100% of the output current flows through the cathode. That places
the output and input in series.
Adding a series resistor there adds negative feedback that is
always very near or in the phase relationship with anode current.
>
> I'm not saying the resistor isn't advantageous, just that it isn't
> really negative feedback. Comments?
>
> 73, Bill W7TI
It's an old time-proven method that works in grounded grid as well
as grounded cathode. Draw it on paper, and look at the voltages.
73, Tom W8JI
w8ji@contesting.com
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