The integrated circuit used in this 70's application is not common today. The circuit consists of a small audio amplifier with few external components.
This coupler allows the triggering of a TTL port or flip-flop from an SCR. The resistor R must be...
This amplifier with very high input impedance was suggested by Texas Instruments in a manual of...
This circuit was found in a 1980s documentation for amateur radio. The circuit makes use of...