[TMC] PAL 350 update

Chris Bolkan bolkyboats at gmail.com
Thu Oct 21 23:02:57 EDT 2021


Hi TMC lovers!

After Gary explained to me that the capacitor was on top of the tube socket
(thanks Gary!) I removed the ceramic chimneys and everything became clear!
Of course I felt like an idiot, but ya never learn if you aren't willing to
look like a fool once in a while.

Once I found the caps they were easy to evaluate. Capacitance of both
measured almost exactly the same at around 1450pf. Nice. They measured open
circuit >20 megohm with my DVM, and hipotted to 600V with no leakage. I
stopped at 600 just because I don't know the cap voltage rating and 600 is
much higher that the screens will ever see.

So.....the caps are fine. Great news!

The not so great news is I am back to the drawing board as to why I can't
get more than 50 watts or so out of the amp and why when tuning it up
regardless of plate current draw, I do not see any change in screen
current. Hmmmmm.

Thanks to everyone for all of the help so far! This is a wonderful group.

Best regards,

Chris
KI7NXY


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