This circuit is from an Electronics World of 1967. The described calculations can be applied to equivalent circuits with modern transistors.
The basic circuit of a flip-flop for use as a frequency divider or one-bit memory is shown here....
This circuit is from an American 80's documentation. The integrated circuit is from the time and...
This circuit was found in an old publicatio n from the year 1958. The circuit controls an external load by...