[Amps] 4CX1500B help needed...high screen current in HF-8020 PA

Paul radioboy at telus.net
Tue Jan 15 00:28:05 EST 2013

Maybe I'm worrying about nothing...how does one interoperate this paragraph
from the Eimac data sheet? They are talking about the 12W screen diss limit

"the screen power should be kept below this
level. The product of the peak screen voltage and
the indicated dc screen current approximates
the screen input power except when the screen
current indication is near zero or negative. In
the usual tetrode amplifier, where no signal
voltage appears between cathode and screen,
the peak screen voltage is equal to the dc screen
voltage. Experience has shown that the screen
will operate within the limits established for
this tube if the indicated screen current, plate
voltage and drive voltage approximate the
"Typical Operation" values."

The multi meter has 2 positions for screen current "Screen +" and "Screen
-". So if the meter is reading 35mA on the "Screen -" does this mean there
is no power being dissipated in the screen and I have nothing to worry



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