filter-凯发k8国际手机网页

filter is a kind of the device that allowing a certain part of the frequency of the signal through smoothly, and inhibit the other part of the frequency of the signal. can pass the frequency range of the signal in the filter, known as the passband; on the other hand, the signal attenuation or completely suppressed was very frequency range is called the band rejection. it is small with firm structure and high stability etc.

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