This counter was found in the November 19983 issue of Radio Electronics magazine. The power supply can be between 3 and 12 V typically. The counting speed depends on C1.
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...