5 Element Beam/Coax Length

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5 Element Beam/Coax Length

Post by RodinKy » Monday, 17 April 2017, 3:59 AM

Bought a beam from an individual and it has about 100 ft of RG8 coax attached, which is about 60ft more than I need. I was told by the previous owner not to shorten it because it would change the SWR. Is this true?

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Re: 5 Element Beam/Coax Length

Post by PA629 » Monday, 17 April 2017, 4:07 AM

If coax length changes SWR, then you have other issues with the antenna system's tuning. Changing coax length can make you see a different reading on an SWR meter, but it's simply a band-aid, not a cure. Coax length is just another 11 Meter Myth.

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Re: 5 Element Beam/Coax Length

Post by Slim Pickins » Monday, 17 April 2017, 4:20 AM

There is a pretty good chance you will see a change in SWR just by swapping the entire setup from his place to yours. There are a lot of factors that can affect what you see on a meter. Just put it up with the cable you need and tune for best performance at your location.

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Re: 5 Element Beam/Coax Length

Post by MDYoungblood » Monday, 17 April 2017, 4:57 AM

Like the others said, coax shouldn't change the SWR but you will probably be taking the antenna apart to transport it to your house. If you don't have a manual to put it back together you can most likely find it on the antenna manufacturer's website or CB Tricks. I would take a real good look at the old coax and since you only need half buy a new 50ft length, would be better off with new to start out fresh.



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