This simple step of low power audio is from a 1975 documentation. The transistor can be a BC548, and the transformer of the type found in small transistor radios and recorders of the time.
This simple pole search or neon probe for the 110 V or 220 V power grid has nothing unusual, being...
This transmitter was found in an old publication on espionage. It applies a signal of a few...
Maxim MAX20056B 6 Channel High Brightness LED Controller Maxim Integrated makes available through...