This 4093 IC continuity tester was found in the November 1986 Radio Electronics magazine. The circuit powers a ceramic buzzer with a frequency setting.
This circuit, in addition to transforming a sinusoidal signal into a square, shifts its phase. The...
The transistors on this circuit can be the BC548. The circuit is from English documentation from...
In the figure we have three voltage doubler configurations that can be used in high and low...