This is a battery powered 3W power amplifier using germanium transistors. The circuit is from an English documentation from 1967. The transistors are from the time.
This relay circuit with a dual channel MOSFET (not very common today) was found in an old American...
April 2017 - Mouser Electronics owns standard Qi wireless charging coils for a power range of up...
This circuit was found the Optoelectronics Sourcebook by Texas Instruments. Any phototransistor...