At 09:26 AM 8/7/97 -0700, you wrote:
>Hi Phil;
>
>On the 77 grid trip.. I don't know about the "all". There seem to be many
>flavors of the 77. From my manual (model 77, no D) "Alpha 77's grid
>overcurrent relay system will not permit the amplifier to be grossly
>overdriven.." I've tripped the relay; it's in there.
Thanks, Peter, I stand corrected on the grid-trip on the 77. I have only
seen 1
or 2 at flea markets, and never a manual. Too bad they did not continue the
circuit in the 77DX/SX models.
All this arguing about grid dissipation is moot. Grid-trip circuits work on
current, not watts. The important thing is that a single 8877 grid be limited
to 70-90 ma at all times, and as Tom said, be a very fast acting circuit.
This will protect the tube in case of loss of load or light loading.
I never cease to continue my education here on the reflector....thanks!
(((73)))
Phil, K5PC
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