"Levent Sasmazel" wrote in message
...
Folks,

Thanks for all this valuable info. I did check a few things more. Power
outlet is showing 124 Volts on my Fluke. When I turned the amplifier I
am not seeing any voltage changes on my outlet. I did take a visual look
to the 3-500Z. I am not familiar about this tube but when I do up side
down very gently I do hear a metallic click noise. It looks like some
thing inside the tube is loose. I did not load any RF to the amp yet. I
don't want to guesswork anything Ameritron manual says 3100V I have to
see it at least 3000V. 600V difference is big. Is any one see low
voltage on the soft or bad 3-500Z ???


If there is something wrong with the 3-500 to cause low plate voltage, the
plate will be glowing red with out any RF drive to it. This will indicate
high current and the tube is bad or the bias circuit is bad. If the tube is
soft or bad in any other way the plate voltage will be on the high side as
it is not drawing much current to load down the plate power supply. Too
low of a plate voltage indicates something is wrong in the power supply
(provided it is getting the correct primary supply ) or as was mentioned if
you are using the built in meter,something is wrong with it or the resistors
that determin the voltage range.