This is a Japanese commercial radio from the 60s. The superheterodyne circuit of 7 transistors for medium waves has 200mW of output when powered by 4 common batteries.
This simple calibration circuit consists of a crystal oscillator that generates an accurate 100 kHz...
This circuit produces a low frequency magnetic field used in old inductive remote controls with a...
We found this circuit in a European publication from the 1970s. The transistor is made of...