If someone chokes a person, they can’t breathe, the flow of air is stopped. The name Choke comes from same idea. There is some energy that we want to Choke or prevent flowing in our circuit in or out of our circuit.
Similarly in power line carrier communication, we choke off carrier signal from entering into the power circuit which is done by a Choke Coil popularly known as Wave Trap.
The Choke action is basically an appropriate size of reactance (inductive resistance) for the frequency of what we want to stop flowing, and of course whose reactance doesn’t have an effect on the frequency of proper signals. This takes advantage of the frequency dependence of reactance.
Chokes are a necessary circuit design element because there is so much noise about. Noise here means all the electromagnetic signals around that aren’t part of our main design that might affect.
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