This circuit has a visual indication of activation and is suitable for people with hearing impairments. The circuit was found in the March 1974 issue of Radio Electronics magazine.
This circuit is from an article in Radio Electronics magazine from August 1972. The circuit is...
Found in 1969 RCA documentation, this circuit maintains constant current in the filament of a lamp...
The integrated circuit used in this application is uncommon today. The circuit is from American...