Using a capacitor as a sensor, this circuit was found in the 1989 Radio Electronics Experimenter magazine. The circuit must be assembled in a shielded box.
Measuring capacitances and resistance this simple instrument was found in Radio Electronics...
The LM143 integrated circuit is a high voltage operational amplifier from National Semiconductor that is...
We found this circuit in the November 1985 issue of Radio Electronics magazine. It uses TTL...