This circuit was found in a 1980s documentation for amateur radio. The circuit makes use of components of the era, but modern equivalents can be used.
This second-order filter was found in old American documentation and can be applied to other...
Found in an old Elektor, this circuit uses two 7-segment displays to indicate the volume of an...
Found in a 90s Popular Electronics, this circuit makes use of power MOSFETs. Equivalent MOSFETs can be...