[AMPS] AL1500

[paulc@mediaone.net (Paul Christensen)]

> Were there "known bad runs" or lots of 8877s?  Sounds like maybe
> there were.

Absolutely.  And, there may have been more than one "bad run" on these tubes.  
I do know that in 1980 it was a critical issue for
Eimac.

As I indicated in my previous message, I went through ~ 10 new Eimac 8877s 
before finding one that would produce ample emission.
The problem manifested as low output power and low overall transmitter 
efficiency.  Perhaps someone can explain the mechanics of the
"filament poisoning."  Eimac's Ken Atkinson explained it to me at the time, but 
I have too many cobwebs to clear out after more than
20 years!

-Paul, W9AC


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