This 1000: 1 voltage-controlled filter circuit was found in an Electronics Today International in a 1980s edition. The circuit is based on components of the time.
This circuit with regenerative action was found in the June 1986 issue of Radio Electronics...
This circuit, shown in the figure, is also suggested by Texas Instruments and shows how to control...
The speed of the motor connected to this circuit depends on the amount of light that strikes the...