genie in the can

12-40 — elektor december 1980 genie in the can R. Wenzelburger Our canned genie is extremely lazy. It prefers to lie flat on its back in the can, or to relax standing on its head, meditating. It will only allow its master to place it the right way up and as soon as anybody else presumes to try, it will make use of its magical powers and knock the can down. Where does it get these "magical powers" from? Well, actually, the genie isn"t that ingenious at all — he"s quite simple minded in fact, as is the electronics involved. monostable now returns to its initial state, the positive going edge at the output of N7 turns off T1 and triggers the thyristor. The relay in series with the thyristor will therefore be activated, but because C7 is rapidly discharged through the relay coil the current through Thi1 will drop very quickly to below its minimum holding current. The thyristor then turns off again and the relay will drop out. Activating the relay briefly causes a genie in the can ...