Hi,
A "Ham" radio friend has an old Knight T-150 transmitter. "R33" , 150 ohm 20W, blew apart due to overload. This resistor is in the +800V circuit, which is the Plate voltage for the Output tubes (6146). He replaced that resistor. I told him to remove those Output tubes and measure the plate voltage. When the transmitter was in "Standby" mode, the voltage was
+800V. However, when he switched the Function switch out of Standby, the voltage dropped a lot and he heard a humming sound.
Does anyone have an idea what is loading down the +800V (Output tubes removed)?
Thank You in advance, John N3AOF