Found in a 1965 General Electric circuit manual, this circuit uses SCRs from that time. Modern equivalents according to the power can be used.
This circuit, from a 1968 Electronics World, is fed directly by the rectified voltage from the...
We found this circuit in the Electronics Experimenter Handbook 1983 edition. The circuit uses...
This circuit allows you to program a resistance by combining the selected resistors. The circuit...