[AMPS] AL80 pfffffttttt!!

[John / NS1Z]

Was testing the output of my AL80 (not A or B, or even C!) when the classic
phfZzt sound echoed from the cabinet. When keyed, the grid current shows
negative and little or no RF output power. Plate voltage indicates a slight
increase when keyed, as well.

AMPS 101: where does the novice start (after shorting the B+ to ground) to
isolate the problem. I have already swapped out tubes. Results are
identical with either set.

What is the negative grid current telling me?

Thanks

73 from NS1Z, FN44rn

John Wilcox
871 Route 120
Rumford, ME  04276-3836

fon: 207-364-2246

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