This filter is from a 1977 publication. The circuit employs three 741 or other operational amplifiers. The supply must be symmetrical and the components with (*) are low tolerance.
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...