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 is a well-known oscillator configuration with complementary transistors. In this case, the...
With this circuit from an old 1973 publication it is possible to use a small speaker as a...
July 2017 - Texas Instruments' new bidirectional current controllers LM5170-Q1 for power...