Using the CA3140 integrated circuit, this switch was found in the June 1986 Radio Electronics magazine. Sensitivity adjustment is made at the trimpot in series with the sensor.
This capacimeter was obtained in European documentation from the 1980s. The indicator instrument, a...
This circuit for the logic control of the 555 in a power supply was found in the October 1989...
This configuration with the LM111 was found in your factory manual. The circuit can be implemented with...