Using a 709 integrated circuit this circuit was found in the June 1972 issue of Radio Electronics magazine. More modern operational equivalents can be used. The power supply is symmetrical.
The integrated 4017, a C-MOS counter, is one of the most popular in the design of sequences,...
This simple very low power circuit can be used in a battery powered infrared tone trigger. We...
This timer controls two relays, each with a different timing, activated separately. The circuit is from...