This circuit was found in a Popular Electronics of the 1980s. The microammeter may be the lowest current range of a multimeter. The antenna is telescopic.
Although not using transformers, this amplifier may have difficulty mounting if the original...
This flip-flop or bistable multivibrator is triggered by a signal applied to the base of the...
The integrated circuit used in this regulator is not very common today. The circuit is from old...