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Hi guys, I found few circuits similar to that one but I can't find any proper explanation of working of such circuit other than very very general one. I'd like to know what exactly every element does. Could anyone help me with analysing this circuit ?
If the circuit works, it is only because of the imperfections in the components. As others have pointed out, the capacitors are shorting the aerial. However, electrolytic capacitors are will have a large impedance at cell phone frequencies, so they will be more like inductors for those frequencies.
There are lots of circuits that rely on secondary characteristics of components. The Joule thief circuit is one, as it only works due to inductor saturation.
It's just a basic comparator circuit with hysteresis - take out the IC symbol and replace it with the proper op-amp symbol and it all becomes clear, although one of the caps could possibly be dispensed with.
Lets say I want it to light up the diode when I put my phone next to it when it is calling someone. From your answers I understand it may work just because sth is not working right but the circuit doesnt have any function itself.