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Twisted pair cable is one of the many products of power cord, and it is a relatively common power cord. Generally excellent twisted pair cables must meet the following indicators.

　　 1. Attenuation

　　 Attenuation refers to the signal loss measurement along the link, which is directly related to the length of the twisted pair. Generally, as the length increases or decreases, the attenuation of the signal will gradually increase. In the use of twisted-pair cables, it is necessary to measure all the attenuation within the use range, and take some necessary measures to prevent signal attenuation according to the degree of attenuation.

　　 2. Near-end crosstalk

　　 General crosstalk is divided into near-end crosstalk and far-end crosstalk. Crosstalk in twisted-pair cables is near-end. Near-end crosstalk loss is the detection of signal coupling from one pair of wires to another pair of wires in a UTP link. In this test, a key index—NEXT value—is required, which is also the most difficult to measure accurately. Audemars Piguet Royal Oak Replica Watches In addition, as the signal frequency increases, the difficulty of its detection will also increase.

　　3. DC resistance

　　 DC resistance will consume the signal in transmission and convert the lost signal into heat. Therefore, various twisted pairs of different specifications also have different DC resistance values.

　　 4. Characteristic impedance

　　Characteristic impedance is different from DC resistance. It includes resistance, inductance impedance and capacitance impedance with a frequency of 1～100MHz. It is directly related to the distance between the wires and the electrical properties of the insulator. Due to the distance and insulator of the twisted pair of each specification, the characteristic impedance value of the twisted pair is also different.

　　 The above four indicators are a measure of whether the twisted pair is excellent. Therefore, the power cord manufacturer should perform production according to these indicators to make the twisted pair produced meet the needs of consumers.

Article from: http://www.elejintao.com/newsd-nid-6.html