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Old 08-05-2012, 08:34 PM
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citfta citfta is online now
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Here's another "magical" circuit. This circuit is posted I guess because it lit some Christmas LED lights in a way that was not understood by the originator of the circuit. It is pretty easy to see what is going on with simple electronic concepts. As stated by one of the posters about this circuit it works just as well with a capacitor in place of the coil of wire and brass rod. Of course it does. The coil of wire and brass rod IS a capacitor. And capacitors easily pass AC current. If you use a larger capacitor it will pass more current. They are used for this purpose all the time in motor circuits. As also stated by one of the posters if you put a cap across the output of the bride rectifier the output voltage goes up. That is also perfectly normal. When you are using a meter to measure the DC voltage coming out of the bridge you are only getting an average because of the pulsing of the DC voltage. If you add a cap to the output the cap will charge to the peak voltage if the load is small enough. So it appears the voltage is higher when you add a cap to the output.

Also you should be aware connecting the hot side of the AC circuit back to the ground instead of the neutral is not a good idea. If you have a ground fault circuit breaker it will trip out. And if there is not a good connection all the way back to the main panel your whole circuit could become energized posing a serious shock hazard.


Last edited by citfta; 10-06-2015 at 09:14 PM.
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