Found in Popular Electronics from the 90s, this circuit mutes a scanner's speaker in the absence of a voice signal, thus eliminating the hiss.
This circuit was found in old documentation. D1 can be a diac. | Clique na imagem para ampliar...
The circuit shown was found in a 1967 RCA manual. Modern equivalent components can be used. The...
This shield can be used both to interface microcontroller circuits or TTTL. The resistor in series...