This circuit was found in an Electronics World of 1968. The transistor can be any general purpose and the double T must be set to R3 for the desired effect.
A flash of light on one sensor or the touch of your fingers on the other type of sensor will turn...
Found in the September 1992 issue of Radio Electronics magazine. This circuit generates pulses that...
September 2017 - Littelfuse's Polyswitch SMD Resettable PTCs can now be purchased from Mouser...