The indicator for this circuit is a 0 to 1 mA milliammeter. The operational is from the 70s, when the circuit was published. Modern equivalent can be used.
Found in a Maxim documentation from the 90s, this circuit produces a voltage of 5 V from an input...
Unlike the previous one, this circuit is intended for the reception of frequency modulated signals...
This circuit was obtained from Popular Electronics from March 1967. The transistor used is from...