This control circuit using a low voltage switch was found in the September 1987 Radio Electronics magazine. The triac must be matched to the load and the mains voltage.
This filter that rejects determines frequency (notch) was found in a Popular Electronics of 1993....
This circuit operates with frequencies from 0.5 to 400 MHz. We find it in a 90’s NASA...
This circuit for adjusting sources simulating a load was found in a publication from 1993. The...