This circuit triggers an LED when the input signal exceeds the peak, or the value set in RV1. The transistors can be the modern equivalents BC549.
Found in a 1970 publication by General Electric, this circuit makes use of a mobile...
This circuit switches on an external load after a certain interval given by the capacitor. The...
Using common SCRs like the TIC106, this circuit is loaded with incandescent bulbs, but can be...