This circuit was used in tape recorders to clear the tape of any previous recordings for a new recording. The circuit is from a Radio Electronics dated September 1982.
This circuit using only transistors was obtained from Ferranti's 1969 documentation. It can be...
This sensitive circuit can be designed with FETs such as BF245 and MPF102. The sensor is a silicon...
Found in Popular Electronics from the 90s, this circuit generates two tones that are selected by a...