Carl says
>3. Use of a suitably sized parasitic suppressor resistor and phase out
>carbon composition. A 5W metal oxide should be the minimum for 3-500Z
>size tubes; a pair of them for the 4-1000A.
I agree with him. However, I prefer 20 watt solid carbons - hard to get,
about 1.5 inches long, .375 inches diameter, unencapsulated, with a surge
capability for 100 microseconds of 10KW. If you can't get them, then I
suspect that there's not much around that's any better than Carl's 49c
resistors from Mouser.
To Carl's desirable features, I think I'd add step start on the
filament/heaters, as well as on the HV. A nice touch is an interlock from
the bandswitch to force the amp into the receive/standby position if the
bandswitch is turned with the power on.
73
Peter G3RZP
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