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 version of the Pierce oscillator with the 2N3904 was found in the January 1994 issue of...
This circuit sources a Constant current to a load. The current is determined by R2. In the...
This is a very simple atomic radiation detector circuit using a Geiger-Muller tube. The circuit was...