This circuit was found in a 1945 publication. The circuit was stated to be part of a walk talkie. Note that, as it is a portable assembly, it was powered by batteries. The jack was for microphone insertion.
This circuit with the LM741 operational amplifier can be applied to other operational amplifiers. We...
This circuit came out in the American magazine Electronics Now, in a 1993 issue. The magazine no...
This small source was found in an English documentation from 1970. The diodes can be 1N4002 for...