Well, I can't say that these tubes spent their entire lives in an AL-800H -
just don't know. This amp had been abused before I acquired it and it's
entirely possible that the tubes it came to me with were not original. If I
had to guess, I'd say that this amp had been used in a continuous output
mode such as RTTY or SSTV at above the suggested output. The 160/80 meter
coil plastic rods had melted allowing the coil turns to collapse into one
another. Not something that would have caused the gold problem maybe, but
indicative of abuse at any rate. I find that the grid protection circuit
works quite well and have never seen any indication of instability in the
amp.
> -- On the phone Monday, a friend who attended Dayton told me that the
> man in the Ameritron/MFJ booth told him that it was impossible to
> evaporate gold from the 3cx800A7 grids in an AL-800H because of the
> built-in grid protection circuitry.
> >
> cheers, Floyd
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
> www.vcnet.com/measures.
> end
>
>
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