This variable filter circuit was found in July 1975 Radio Electronics magazine. The circuit uses 3 general purpose op-amps like the 741 and must use a symmetrical source.
This circuit provides a power of the order of 2 W, characterized by high performance. The output...
This 12 V to 110 V inverter with 100 W was found in a 1977 Signetics manual. The transformer must...
The gain of this amplifier is given by the components indicated in the formulas next to the...