In the figure we have one of the many options found in this section for an intercom using ordinary phones not in use. This was obtained in a Popular Electronics from the 90s.
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...