This long interval timer was found in the September 1976 issue of Radio Electronics magazine. The output can be used to control a relay. The circuit achieves timings of up to 14 hours.
The modified Hartley oscillator, seen in figure 2, can generate signals ranging from 3 MHz to 10...
This circuit produces a high voltage (above 5,000 V) to ionize the air around a needle that acts...
Found in American documentation from the 90s, this circuit provides three timings given by the...