The indexes that should be paid attention to in the pickup are: bandwidth, impedance, input and output level, maximum output power, signal-to-noise ratio and non-linear distortion.
Is relatively fixed, but as a result of audio applications such as: the arrangement of point to point probe (pick-up), parks and other places of background music or intercom between two places, they are different to the requirement of audio transmission, consider when purchasing, should according to actual situation.
Audio option besides the imlet also points according to the actual needs a one-way and two-way audio, audio application one-way places such as: audio transmission pick-up in monitoring alarm signal, it's just the audio signal from the front back to the control center, the application of two-way audio places such as toll station in places such as audio speaker.
Audio pickup access backend equipment includes: optical transceiver, embedded hard disk video recorder, network hard disk video recorder, network servers, network cameras, etc., all should pay attention to the type of access terminal.
At present, the market is all pickup Line (linear output level), and some small manufacturers on the market of hard disk video recorder and network camera part USES a MIC (MIC) input, does not match on the audio signal transmission. Pick-up is difficult to attain the best performance, recording fuzzy, noise problems such as big.
More so some unscrupulous pickup supplier can promise the so-called passive pick-up match, in fact, that kind of practice is to modify the output resistance, just make a little change, also can not reach the Line (linear output level) effect!
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