This power supply circuit for high power audio amplifiers was found in Radio Electronics from the 90's. Power MOSFETs admit modern equivalents. The output current is 5 A.
This small crystal microphone transmitter was indicated in an 80s spy book. The range depends on...
The figure shows how to use an operational amplifier with a low impedance head. The gain is...
Voltage comparators, such as those in the LM139/239/339 series, consist of devices that can be...