"James Skalski" wrote in message
news:gQ88f.5702$0V6.3968@trndny06...
Has anyone used a VNA to set up taps on an amplifier tank circuit or used
one to set up taps on a coil in a transmatch? Maybe a small capacitor on
the anode lead instead of the finals to match capacitance and then measure
from the output of the amplifier with antenna relays in "on" position. (no
other power to the amp

You bet Jim, ONLY way to do it! Put the tube in the socket, place a 1/4 watt
resistor plate to ground of the value of your plate load, stick the VNA on
the output port (Refl mode) and tune for maximum return loss. You should
readily get 40 dB to 50 dB, log the settings and you're all tuned up. (Don't
forget to pull the resistor before you apply power, although if you do, it
will remove itself in short order.)

You can measure the caps and place tap on the inductors where you get return
loss or measure the inductor and tune the caps for RL. Use the data in the
handbook for expected values for the plate load resistance transformation
and whether it's a Pi or Pi-L network.

Regards
W4ZCB