>
>Replaced the diode on circuit board, it was on schematic, and was bad.
>Replaced with a IN4141 because that was all I had. No difference in the
>wild red glowing of plates.
>
>Checked zener diodes in center tap of filament transformer. Red lead of
>meter to threaded post of zener diode #1 .559 mega ohms. Reversing leads
>1.35 mega ohms.
>
>Zener #2 red lead of VOM to threaded post 1.4 mega ohms. Reverersing
>leads, 14.1 mega ohms.
>
>Running amp with zeners disconnected, still big red glow and 300 ma on
>plate current meter.
>
? Could be a grid/fil. short. On page 15 of the Sept., 1990 issue of
*QST* Magazine, there is a photograph of the insides of a3-500Z with a
grid/fil. short. // If the grid/fil. potential measures 0v on
standby, you have a grid/fil. shorted tube. // There is a photo of a
parasite-arced AL-82 bandswitch on my Web site.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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