We found this solid-state relay circuit that can function as a shield in a Radio Electronics magazine from December 1989. The optocoupler is a phototransistor type.
We found this circuit in the 1983 Radio Electronics Special projects magazine. The components are...
This amplifier can work with voltages between 12 and 22 V. This means that we can use it in the...
This circuit was found in a Popular Electronics from the 90s. The counter circuit is not common...