This circuit was found in the October 1983 Radio Electronics issue. It is applicable to old analog telephones. The circuit uses common components.
The integrated circuit used in this application is not currently common. The circuit is from 80s...
This circuit was obtained in an Electronic Design from the 90s. The circuit uses transistors from the...
This circuit hás a Power output of more than 1 W. It is used in small experimental or low power...