>>>Eimac rates the 8877 at 20w max. grid dissipation. Normal grid/cathode
>>>potential is 55Vrms. With 75mA of grid current, dissipation is approx.
>>>Why do you limit grid current to 75mA, Phil?
What would you limit the Ig to on your amp, Rich?
Apparently, you think 75 ma is too low, although the tube is maxed out
at 60-65 ma. Limiting the Ig to 75 ma allows the tube to operate at its
maximum power output. Would you put a 30 amp circuit breaker on a
circuit in your home that is only rated for 15a?
I am in the business of having
>>to buy tubes. Prices are soaring, as I am sure you know.
>>Why push your luck on a very fragile grid
> I have a dissassembled 8877 in front of me. The grid is composed over
>of slightly over 100 gold-plated molybdeum bars Elevating such a grid
>to a high enough temperature to boil gold would require considerable
>>When lightly loaded, by mis-tuning or wrong antenna, the 8877 Ig soars more
>>rapidly than any other tube I have used. Alpha 77 series owners will certainly
>>agree with this!
>Alpha 77s do not have a truthful grid-current meter.
I was not referring to meter accuracy, Rich. You are correct; the Alpha Ig
meters are off by 100%. I was referring to the rate of change when the
loading cap is moved about.
The toughness of the grid on the 8877 is a relative term. Comparing it to
the grid of a 4-1000A, which a lot of us cut our teeth on, it is fragile.
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