Found in Popular Electronics from August 1956, this clandestine listening amplifier uses contemporary tubes with 1.5 V filament for battery power, in addition to the high voltage battery.
Electronic Ear (T1524E)
- Details
- Written by: Newton C. Braga
Found in Popular Electronics from August 1956, this clandestine listening amplifier uses contemporary tubes with 1.5 V filament for battery power, in addition to the high voltage battery.
