Found in Popular Electronics from the 90s, this circuit consists of a timer that turns off the power of a circuit after a time determined by C1, saving the battery.
Found in a 1990s US publication, this alarm circuit detects when a light beam is interrupted. Optical...
This circuit for a commercial compact digital multimeter was found in the March 1979 issue of...
The flasher we present was found in a 1982 publication, shown in the figure. What we have is a...