This 4-tube counter was found in Radio Electronics magazine from December 1959. The circuit uses a coil as a sensor to detect the passage of metallic parts or magnets.
This circuit was found in old documentation, but the setting applies to any operational. Resistors...
We adapt this circuit of Radio Electronics - March 1990. The magazine no more exists, but the...
The circuit of the figure consists of a motor timer that can delay drives for up to 15 minutes....