This small 1 W amplifier uses a Motorola integrated circuit from the 1970s. The integrated circuit used is uncommon today and the power supply does not have to be symmetrical.
This precision speed control was obtained in an Electronic Design from the 90's. The output final...
Using the name of varactor this circuit was found in the Radio Electronics magazine of July 1982....
This trigger circuit was found in an American documentation from the 1980s. The amplifiers used...