Re: CONtrol of ELectronic RADiation

[Bill Piacentini <billpi@ll.mit.edu>]

Hello Folks:
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,
Bill Piacentini
billpi@LL.MIT.EDU
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 
unique format!