Use of inductor coil: choke, filter, shock

● Choke: In low frequency circuit used to prevent low frequency AC; Pulsating DC to pure DC circuit;It is commonly used in the middle of two filter capacitors at the output of a rectifier circuit. In the high frequency circuit it is to prevent the high frequency current flow to end of the low frequency, in the old regenerative radio the high frequency choke is applied.

● Filter: The same as the above theory, it is also to prevent the pulsating DC current after rectification from flowing to the pure DC routing choke (in order to simplify the circuit and reduce the cost, the choke is replaced by a pure resistor). Two capacitors (electrolytic capacitors) compose the filter circuit, the pure DC is obtained by using the capacitor charge-discharge function and choke ring to pass DC and block AC characteristics to complete smooth DC.

● Shock: If that rectification is to turn alternating current into direct current, so shock is to turn direct current into AC reverse process. The circuit is called an oscillator. Oscillator waveform: there are rotational wave, sawtooth wave, trapezoidal wave, square wave, rectangular wave, peak wave, frequency from a few Hz to tens of GHZ, in the field of wire and radio is very widely used.

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