Found in a 90s 303 Circuits, this circuit triggers a load from a 50 mV audio signal. When the signal ceases, the charge remains active for 2 seconds.
This circuit was found in an English magazine from 1983, but it can be assembled with BC548 for...
The basic circuit of a flip-flop for use as a frequency divider or one-bit memory is shown here....
This is a transistor flip-flop suggested by General Electric in a 1966 paper. The transistors are of...