This circuit was found in a 1980s documentation for amateur radio. The circuit makes use of components of the era, but modern equivalents can be used.
The 4093 or any other NAND gate can be used for the very sensitive configuration of a R-S...
This circuit was obtained from Radio Electronics magazine of June 1964. The SCR may be a modern...
This circuit causes an LED to flash if the monitored voltage exceeds the value set in the pot. The...