This circuit for very long-time intervals was found in the March 1993 Radio Electronics magazine. Times of several days or even weeks can be achieved depending on the value of C1.
) This variable frequency oscillator was found in an old American documentation. Transistors allow more...
Found in the September 1982 issue of Radio Electronics magazine, this circuit triggers a relay...
Using a 106 series SCR, this circuit was found in the May 1971 Radio Electronics magazine. The...