The circuit presented is a Japanese commercial radio for AM with 50 mW of output power, powered by 9 V. The circuit is from the 60s, having been found in documentation of the time.
This very simple circuit uses a phototransistor and a very sensitive relay (reed type) being used...
We found this circuit in Radio Electronics magazine from January 1958. It uses a neon lamp as the...
The integrated circuits in this application are not very common today. One consists of an A / D...