Ring modulation is an effect processing signal in electronics, in relation to amplitude modulation or mixed frequency. It is realized by the multiplication of two signals, where one is typically a sine wave or another simple waveform. It is called ring modulation because the analog diode circuit used initially to apply this technique took the form of a ring. This circuit is similar to a bridge rectifier, except that instead of the diodes face left or right, they go clockwise or counterclockwise.
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