Have a problem I caused when I applied much too much power to my ETO 76PA.
I was running a 1000MP Mark V in class "A" mode that limits output to about
50 watts PEP which is about right to drive the three holers. Unfortunately
I had returned to standard operation with the 1000MP and ran 200 watts RF
into the 76PA. Heard some noise, arching, spitting and soforth before I
realized what I was doing. Took out a couple of transistors on the control
board and obviously did something to the rf deck..
Got the control board fixed but apparently I did something to the RF
section. Pulled the three tubes and checked them individually in my other
76PA. The tubes all check fine. Have looke carefully for some sign of
arcing and componet failure and can see nothing that would indicate a burned
part. Also the power supply section is working just fine.
But when I apply drive I can't get the amplifer to load up, that is hardly
any grid current or plate current and no output when I increase drive to
the amp.
Any suggestions what to check? (I also checked the five 470 ohm drive
resistors in the tube compartment. They are fine.
Thanks much. Van, K7VS
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