> internal resistance to limit start-up current. (I don't trust it's
> step-start circuit to provide a suitable slow-rise since the HV isn't
> brought on-line until the timer completes it's cycle)
Great points, Dennis. I have often thought about adding a separate HV
contactor relay to both Alpha amps for the purpose of applying HV at some
reasonable time after lighting filaments. My gut has never been comfortable
with HV being applied to the anode at the instant when filaments are lit.
Of course, with indirectly-heated tubes, the real issue is to refrain from
RF excitation until the cathode comes up close to filament temperature. But
even on the 70V with its directly-heated cathode, I would probably "feel
better" with something like a 5-10 second HV delay.
Paul, W9AC
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