This UPS circuit was published in the March 1985 issue of Radio Electronics magazine. The components used are still common, although some may be difficult to obtain.
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...