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 circuit trips by shorting the load to quickly blow the fuse when the voltage exceeds a...
Epson SG 8018 Epson Crystal Programmable Oscillators Available from Mouser Electronics, these...
This circuit works with the previous two by demodulating the signals received modulated in FM. The...