Rich says:
>? A filament-voltmeter for the 3-500Z, in lieu of a grid-current
meter,
>would have added little to the price. A 1mA DC movement would have
>sufficed. A schottkey rectifier costs under $0.50. The most
expensive
>part would have been the custom AC meter scale. . Typical fil. v.
in a
>SB-1000 is c. 5.3v.
Agreed. But perceptions come into this too. I guess many hams wouldn't know
what do with the filament rheostat; some would turn it full up to get more
emission, some right down for life, and then run out of emission.
Funny thing, filament rheostats went out of fashion after dull emitter tubes
came along, round about 1923-24 time. 75 years later, some of us like the
idea of bringing them back..........
My new amp will have a constant current supply, adjusted to get the right
volts on the heater, with no big surge at switch on. But the SMPS for that
was $10 at a hamfest flea market....
73
Peter G3RZP
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