Thanks to everyone who replied, it was all very useful stuff. Terry, W6TG
hit the proverbial nail on the head with his comments:
" > I would try one more 8877 tube. I have seen similar indication from a
flat > 8877 or one with a open fillament. Also make sure the fillament
voltage is > present at the tube socket with the tube plugged in. If you
have a burned > molex connector pin it could show filament voltage and
when you plug in a > tube (low impedance load) the bad pin connection
opens up and then read no > fillament voltage on tube. "
Terry, you couldn't have been more right! Pin 4 of the molex has the
solder melted off the connection and is very flaky. Actually, looking at
it closer there doesn't seem to ever have been solder there.... Now
repaired and generating heat and RF again, now that the tube's more basic
requirements are being met.
Phil, K5PC, thanks for your input and I will look at some of the areas you
mention before I button it up.
Thanks again for the right on advice.
73 Don
VE6JY is Don Moman email: ve6jy@freenet.edmonton.ab.ca
Box 127 Lamont, Alberta
T0B 2R0 (403) 895-2925
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