This triac circuit turns on a load after a time of 8 to 80 seconds adjusted by potentiometer R7. The circuit is from a Radio Electronics from June 1970.
This circuit uses two light-activated SCRs or LASCRs, uncommon components today. The power depends on...
This type of configuration can be seen elsewhere in this section. This is from a 1965 General...
Crystals from 100 kHz to 1 MHz can be used in this 1957 Raytheon circuit. 4 can have values...