This reader with TTL logic compatible output uses an LM139 comparator. The circuit was found in the 1994 National Semiconductor Linear Applications Handbook.
This simple circuit can be used as audio output stage for intercoms, experimental radios and other low...
This simple solar powered MW receiver was obtained from a 1974 Popular Electronics. The transistor can...
This flashlight project with a blinking light that makes it easy to find was found in the January...