This bistable circuit that drives a relay with a pushbutton was found in the March 1pp6 issue of Electronics Now magazine. A common bipolar with a 1k resistor at the base can be used in place of the FET.
Figure Bellow shows how to interface CMOS circuitos with TTL using the 4049 or 4050 IC. The power...
This circuit is from a manual from the 80's and the operational one used, uncommon nowadays, can...
Based on National Semiconductor's LM4130 reference circuit, this circuit was found in Internet...