[Amps] Re: Rm resistor

[David C. Hallam]

I had intended to do something similar to this to a new amplifier to
establish the correct position for the taps on the coils.  I am a little
puzzled about how to go about it for a Pi-L network.  I plan to use a
Boonton RX meter to make the measurements.

Since there are two coils to be adjusted, it would seem that first you have
to set the tap on the Pi coil using the design image impedance and circuit Q
and the calculated value of tuning capacitor capacitance, then not changing
the Pi coil and tuning capacitor settings, set the output coil tap using the
calculated capacitance value for the loading capacitor.

Is there a fallacy in my reasoning or a better way?

David C. Hallam
KC2JD

>Hi All

>For the Pi or PiL  adjustaiment whit the swr analyzer ,it's necessary to
place  a non->inductive resistor egual to the plate impedance,from the anode
tube and the chassis ground.
>I would like to know if in the PiL case ,for  the best result, it's
necessary to place also >the non-inductive resistor egual to RM value ,for
example 300 ohm, from the load variable >capacitor to the chassis ground.

>Many thanks in advance

>73 Luca ik5tsw at virgilio.it