Using two 741 operational amplifiers, this low-pass circuit has a cutoff frequency of 10 kHz. We found it in an article in the magazine Electronics Now from August 1993.
This circuit detects a light window using two operating systems. The circuit is from a July 1992...
This circuit was obtained in a 70s American documentation. The integrated circuits of the time are...
-- This old oscillator takes advantage of a transistor radio output transformer of the time. The 2...