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Re: CONtrol of ELectronic RADiation
Sorry for not responding over the long weekend (FRI to TUES). I was in
Bermuda with Joan for a little R&R.
My Zenith with Eveready A & B batteries can't be found! (Did Joan toss it?)
Everyone is correct except for the "use only in emergencies." Those
portables were sold in the 50's with beach-use in mind. The handle
contained the ferrite loop antenna that increased its gain when you grabbed it.
The 1.5V "A" battery was a parallelepiped (in Zenith's case) supplying both
"heater"(filament) voltage and (grid bias I suppose) to the (usually) five
vacuum tube complement (in parallel). The "B" battery I believe was 45V.
(The term B+ as was pointed out is still used today as (usually) the
Collector(Drain) Voltage (today) or Plate Voltage (back then). [Of course
with Integrated Circuits it is difficult to be privy to the active
semiconductor junction layout!] Cathodes were usually tied to one side of
the filament. However, low noise requirements (with 60 cycles per second
(=Hz) AC voltage filaments) in vacuum-tube amplifiers necessitated separate
cathode & heater(filament) connections to suppress the 60 cps. hum.)
Takin' it Easy99.1,
As we close the 20th Century A.D. with one last year (2000) let me join
with my favorite radio station locally-owned WPLM-FM 99.1 with perhaps the
largest playlist in the free world playing a unique blend of great music by
great artists in wishing everyone success in this its second year of its