The figure shows a typical circuit of a variac with a special transformer with sliding adjustment of the winding turns. The circuit is from an Electronics Now magazine from December 1997.
Other operational amplifiers series, such as the MC34072, MC34074, MC35071, MC35072, MC35074 or...
This circuit with the HA2400 was found in the March 1980 Radio Electronics magazine. The circuit has...
This circuit has two high-impedance inputs. The gain is high and more inputs can be added. Use a...