This simple step of low power audio is from a 1975 documentation. The transistor can be a BC548, and the transformer of the type found in small transistor radios and recorders of the time.
This variable voltage reference uses a Norton operational amplifier. The voltage is adjusted at...
This 6 transistor TR26 commercial radio was sold in Japan in the 60s. It is a super heterodyne circuit...
n be assembled with BC558 transistors for low power transistors and a BD136 for the output. The...