The scenario: I plan to insert a small (.3uH) coil in series with the PA
tube to reduce the tube's output C effects on the higher frequencies.
For the sake of discussion, lets say the target plate load impedance is 5000
ohms, and on 10M the effect of the series coil is to lower the effective
load impedance to 4000 ohms (these numbers are example only).
For initial cut-n-trimming I want to "look" into the PI-net "backwards" with
my analyzer. Do I use a 5K resistor from the plate to ground to simulate
the plate load R - or a 4K resistor?
I'm pretty sure the answer is 5K as the series coil is simply "faking out"
the plate load impedance to the Pi-net. Just wanna be sure.
Thanks! 73, Bill
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Bill Coleman N2BC
http://home.stny.rr.com/n2bc
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