Found in a 1967 Ferranti documentation, this circuit uses a LDR from that time as a sensor. Transistors can be replaced with modern equivalents.
This sensitive touch key appears on this website from other sources. This version was taken from a...
This well-known configuration of the guitar effects pedal was obtained in an English magazine from...
This simple 555 component tester was found in the November 1992 issue of Radio Electronics...