Found in a Popular Electronics from the 90s, it applies to the old answering machines that used tapes. It emits a warning beep on the drive.
The JFETs of this old circuit admit modern equivalents and their characteristics determine the maximum...
This low power audio amplifier was found at 1992s Popular Electronics. Transistors are general...
This circuit transmits in the FM band. It is a good range FM transmitter found in a 90's Silicon...