This circuit is from the Texas Instruments operating amplifier manual. Any operational can be used and the font need not be symmetrical. Rf and Rg determine the gain of the circuit.
This light-controlled circuit uses a 6 V or 12 V relay depending on the supply. The transistor can be the...
This circuit was found in an American publication from 1965. The circuit uses components from that...
This powerful inverter provides a high-quality sine wave signal. I found it in a Radio Electronics issue...