If cable need to build, purchase the optional cut its required length.Its impedance must be the same as that of the existing cable.If this option is available cables is not known, should be guided by the rule: the TV antenna connected cord to the characteristic impedance of 75 ohm antenna radio range CBS - cable with a characteristic impedance of 50 ohms.The same characteristic impedance are cables for computer networks obsolete standard (today such networks are virtually obsolete) The thickness of the cable is selected depending on its purpose.Apply a thick cord is necessary in two cases: a large of its length (to reduce attenuation) and the considerable power of the transmitted signal.If any of these conditions are met, cable must be of large diamete
Before performing any operations with the cables required to unplug all equipment connected to it.Many devices are capacitors, connecting the common wire to one of the network cables.In this case, if at the same time grab for braiding or central core of two cables or two ends of the cut cable, you can get a painful blow tokom.Dazhe turning off all equipment before while touching the live parts of the two cables in any combination, always make sure there is no tension between themusing an AC voltmeter.If cable leads to the transmitter (eg radio Standard CB), should further ensure that no high-frequency voltage on it by a wavemeter.Even with the low power impact of such stress on the skin is able to cause burns.
spliced ​​cable by twisting or soldering can be used only if the equipment connected to them - not passed, because in this connection noticeably worse standing wave ratio that threatens to exit from the transmitting equipment stroya.Vnachale Stripboth cables.Make a longitudinal incision on the outside of the insulation, Unbraid braid, then by pushing it to the side, twist.Then, remove the insulation from the wire cutters central zhily.Soedinite braided cord with a braided else did the same, with the central veins.In no case do not short-circuit between the shield and center conductor.If you use soldering, to implement it quickly, so as not to melt the insulation of the central core, which also threatens to isolate zamykaniem.Vse connections carefully.
much lesser extent changed the standing wave when connecting coaxial cables using connectors.They are of two types: F (TV), and BNC.For transmitting equipment suitable only second.They, in turn, must have the same characteristic impedance as the cable , and therefore available in two versions: SR50 and SR75.Dlya cable connections via connectors purchase the plug and receptacle of the same standard.It is better if they are designed for connection without the use of soldering, so as not to risk a short circuit originated from the melting insulation central zhily.Prisoediniv to one end of the cord plug, another - an outlet, connect them to each other.If the connectors are exposed contacts (usually available in this performance sockets), isolate them.
If the equipment used in conjunction with a cable, a transmission, be sure to check with the meter standing wave ratio, did not come out if this option is beyond the permissible limits.Then proceed to use the equipment.