RadioBanter - View Single Post

October 4th 04, 02:08 AM

(Radioman390) wrote in message ...
B batteries provided the high voltage to the "plates" of tubes. I recall 90
volt units.

A batteries provided filament voltage (1.5 volts) to a lot of tubes like the
1EQ5, where the first digiot indicated the filament voltage, and the letters
the type of tube characteristics, and the final digit the number of pins that
were active.
6 AQ 5 was a 6 volt amplifier with two filment connections, a plate
coonection and two grids.
However sometimes there was a cathode too (I'm getting hazy on this stuff),
maybe the filament didn't count as two.

And "C" cells provided the bias voltage. This was before cothode resistors
became common. I built such a radio years ago. 3 stage TRF. I used "hearing
aid" vacum tubes, with several hundred turns for a "loop" andtenna around the
edge. It was about the size of a VHS tape, but about a third thicker.
Terry