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I'm using RG-213 coaxial cable for two-way ham radio communication. But due to weather conditions, the metallic shield of my coaxial cable (RG-213) become rusty and carbonated.

If I use copper electrical cable 3/.029 as metallic shield with aforesaid (rusty metallic shield ) Coaxial Cable, what will be the result? Will it be the best solution for my damage metallic shield coaxial cable or not? Can i get the best two way communication with this method?

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    $\begingroup$ Is it possible to cut out the damaged section, put connectors on the ends and join the salvaged cable with a "barrel" connector (e.g., 83-1J)? $\endgroup$ – Brian K1LI Apr 4 at 20:10
  • $\begingroup$ What is the maximum frequency that this coax will be used for? $\endgroup$ – Mike Waters Apr 4 at 20:54
  • $\begingroup$ yes Sir it is possible to cut out the damaged section but it will lead approx. 02-03 joint / cuts in 150 feet lenght of Co-axial cable. $\endgroup$ – ajmal nawaz Apr 5 at 9:19
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    $\begingroup$ that aforesaid co-axial cable is being used for VHF band. ( Max. Freq is in between 160-162 MHZ ) $\endgroup$ – ajmal nawaz Apr 5 at 9:20
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    $\begingroup$ Please edit your question when providing additional information; do not put it only in comments. $\endgroup$ – Kevin Reid AG6YO Apr 5 at 16:04
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You cannot repair a coaxial cable by wrapping or replacing the outer conductor (shield) with ordinary wire. The shape of the shield is critical to its functioning (determining the characteristic impedance) and the different impedance created by using differently shaped conductors will lead to reduced performance, and possibly damage your transmitter if it does not have high-SWR protection.

Weather-damaged coaxial cable should be replaced with new coaxial cable. Be sure to apply suitable sealing tape (self-amalgamating tape) to the end connectors after tightening them down if they will be exposed to moisture.


The one thing you can do for damaged cable is to cut off the damaged section and install a connector (a proper coaxial connector, not a splice) to join it to a new length. However, this is not a good idea for outdoor installations since it introduces more places for water to get in.

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  • $\begingroup$ That impedance bump has a minuscule effect below 50 Mhz, as it's only a tiny fraction of the wavelength. $\endgroup$ – Mike Waters Apr 4 at 20:47
  • $\begingroup$ @MikeWaters I understood the question as asking about replacing a long length of shield with other wire. We don't know what the length is (I removed "bump" from the answer to improve it), and the question isn't about HF specifically either. $\endgroup$ – Kevin Reid AG6YO Apr 4 at 20:52
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    $\begingroup$ i m the user of VHF Band.(140-170MHZ). My Tx co-axial Cable is 150 feet and Rx co-axial cable length is 130 feet. this Tx/Rx is with respect to Repeater Station. I m using Diamond F-22 Antenna for Tx/Rx . $\endgroup$ – ajmal nawaz Apr 5 at 9:23
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    $\begingroup$ Images of damage outer shield of coaxial cable will be posted within 02-03 days. it will clear my question to you and then i think i will be better guided by you. $\endgroup$ – ajmal nawaz Apr 5 at 9:25
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    $\begingroup$ @ajmalnawaz Please edit your question when providing additional information; do not put it only in comments. $\endgroup$ – Kevin Reid AG6YO Apr 5 at 16:05
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If part or all of the shield of your coax is corroded, then that entire portion of the coaxial cable must be discarded.

  • The corrosion causes the individual strands of the shield to be isolated from one another, significantly reducing the shielding effect of the braid.

  • It also causes noise to be heard in your receiver.

And as Kevin correctly stated in another answer here:

You cannot repair a coaxial cable by wrapping or replacing the outer conductor (shield) with ordinary wire. The shape of the shield is critical to its functioning (determining the characteristic impedance) and the different impedance created by using differently shaped conductors will lead to reduced performance, and possibly damage your transmitter ...

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