Using the CA3140 integrated circuit, this switch was found in the June 1986 Radio Electronics magazine. Sensitivity adjustment is made at the trimpot in series with the sensor.
This simple Bargraph photometer with 4 LEDs was found in a 1997 documentation. The scale is...
This 7400 TTL circuit has a memory, keeping the LED on when a pulse is detected. The circuit must be...
This constant current source was found in the Linear Applications Handbook of the National...