This telephone circuit was found on a 90's EDN. It keeps a flashing LED to indicate that there was a call in your absence. The components admit equivalents.
This circuit is from an old French publication. With it we can have full wave control of a charge...
This is an improved version of the previous circuit also found in the December 1990 Radio...
This VCO with the 4046 PLL generates signals from 0 to 1.5 kHz. The circuit is from a Radio...