We found this good amplifier in a Japanese publication of 1966. Transformers are uncommon nowadays and the power supply is included. Power is a few watts.
This circuit turns on and off when a short pulse is applied by SW to the input of the first...
We found this circuit in a publication of 1991. The audio amplifier is an operational that admits...
The oscillator of the figure has its frequency determined by the crystal. The indicated value is...