Found in an Electronics World of 1968 this circuit can use any SCR and diodes depending on the load. The circuit is full wave and the unijunction can be 2N2646.
This long delay circuit was found in the July 1973 Radio Electronics magazine. The capacitor...
This basic circuit showing the LM3914 “inside” was published in the October 1980 issue of Radio...
Using only one general purpose transistor this circuit is powered by batteries. The lamp of the...