This circuit with two operating modes was found in the September 1989 issue of Radio Electronics magazine. Other operational amplifiers can be used. The power supply must be dual.
This one is from an 80's EDN. Transistors can be general purpose types. The frequency is...
This power supply is not protected from shorts in the output. Output voltage is given by the...
This static switch or electronic contactor was found in a 1968 Motorola publication. The triac...