This circuit was found in General Electric documentation from 1968. The circuit uses triac from the time as well as transistors that can be replaced by modern equivalents.
This filter, from an audio publication from 1977, passes the frequency range corresponding to the...
In the figure we have three voltage doubler configurations that can be used in high and low...
This circuit was found in Motorola documentation from 1966. The lamps are according to power and...