This amplifier uses an integrated circuit from the 70s, which is no longer common on the market. The circuit was used at the time as a sound output stage for televisions.
This circuit triggers an alarm when the mains power is cut off. The circuit was found in the July...
This acutely tuned circuit was found in American documentation from the 1960s. The transistors are germanium...
This small AM transmitter was found in American documentation from the 1980s. Transistor support...