[Amps] 8877 - HV with heater, or later?

Jim Barber barberaudio at gmail.com
Mon Jan 23 12:26:26 EST 2023


I'm overhauling a vintage 8877 amp, and it occurs to me that I've never
seen a definitive answer to this question:

Should HV be held off on a 8877 until the heater warm-up timer expires?

Not that I claim any particularly deep or insightful knowledge of such
things, but it seems to me that if the cathode has cutoff bias that it
wouldn't make any difference when B+ is applied.

I did find a reference to this question in the amps archives, but every
design I've looked at recently holds the HV off until the cathode is ready
to go.

Maybe there's more to it than I'm seeing? I may use a separate HV switch on
the front panel anyway just to allow for gettering, but I'd still like a
consensus on the question.

Thanks!
Jim N7CXI


More information about the Amps mailing list