This circuit featuring a new quadruple operational amplifier was found in the March 1980 issue of Radio Electronics magazine. The circuit is to be powered by a symmetrical 15 V source.
Found in old English documentation this circuit can be made with a BF245 or equivalent. Coils are...
This circuit is indicated for the generation of signals in the 40 meters range. The circuit was...
Carbon microphones are no longer used in most projects. However, finding one in the scrap metal, it...