The purpose of this circuit, which we found in the November 1986 Radio Electronics issue, is to determine the voltage across a zener diode. Several test currents can be selected.
This small FM transmitter for clandestine listening has a good range and should be powered by a 9...
This circuit has a high input impedance and provides a good signal at its output. The power must...
This traditional metronome configuration uses unusual transistors in the original version, but it...