Found in a 1967 Electronics World, this preamplifier uses an integrated circuit from that time, difficult to obtain today. The maximum frequency is 15 kHz.
We found this circuit in the June 1991 issue of Radio Electronics magazine. The circuit can be...
This precision circuit, which also functions as a bridge, was found in a February 1967 Popular...
We found this circuit in an old documentation from the 70s. The text is the original one of the...