This circuit is from a 1980's documentation for telecommunications. The circuit is used in SSB and the diodes must be suitable types for the application. The audio input is low impedance.
Found in a 1960 Sylvania manual, this circuit is intended to measure audio signals frequency....
We found this circuit for vocal effects in the September 1990 issue of Radio Electronics magazine. The...
Depending on the output transistor used, this transmitter can provide power from 1 to 3 W. The...