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Kenneth Scharf · January 10th 10, 08:16 PM posted to rec.radio.amateur.boatanchors

wrote:
On Jan 9, 8:41 am, "Antonio Vernucci" wrote:
In the AM transmitter I am building, the power supply is structured in such a
way that it is not possible to measure the final tube plate current at a
low-potential point.

So I have decided to connect the tube cathode to ground via a 1-ohm resistor and
measure the voltage that develops across that resistor.

I know that, doing so, I will be measuring the sum of plate current (around 200
mA), screen current (around 20 mA) and grid current (around 7 mA). But tuning
the transmitter Pi network for minimum total current should still work fine. Any
comment?

73

Tony I0JX
Rome, Italy

You are exactly right..Be sure to bypass the the cathode resistor with
something like a point 01 cap . Good luck W4PQW
The only thing you won't be able to do is to measure the plate input
power of the transmitter, which for your application isn't a requirement.