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Author Topic: Coaxial antenna connection question  (Read 174 times)

Offline Treehouse SWL

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Coaxial antenna connection question
« on: March 12, 2019, 1915 UTC »
Question, as the technical side of antennas and feed lines, etc., is just at the edge of my understanding ...

I currently have my antenna feedline strung through a window, which keeps the old window cracked open just a bit year-round, which is less than ideal.

But I've located an old hole in my exterior wall for a cable TV connection, and there's an installed coaxial outlet on the inside of the wall there. It's even in just the right place on my house for my listening spot!

So if I use this to attach my outdoor feedline to the antenna on one side and then screw in a coaxial cable on the other side, leading to my receiver (which will use a coaxial-to-3.5mm adapter), is that whole setup likely to cause any adverse noise effects or significant signal loss?
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Offline Josh

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Re: Coaxial antenna connection question
« Reply #1 on: March 12, 2019, 1935 UTC »
If the coax is good and no shorts in the connectors, I doubt you could measure the loss at vlf to hf.
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Online redhat

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Re: Coaxial antenna connection question
« Reply #2 on: March 12, 2019, 2356 UTC »
As long as the shield integrity is intact, I suspect you'll have no issues.

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Offline ChrisSmolinski

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Re: Coaxial antenna connection question
« Reply #3 on: March 13, 2019, 0955 UTC »
I don't see any major problems, as others noted the coax loss will be insignificant at HF.

You may want to use a transformer to connect the antenna to the coax.
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Offline Treehouse SWL

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Re: Coaxial antenna connection question
« Reply #4 on: March 16, 2019, 0259 UTC »

Thanks to all for the advice! I'm always learning something new from the experts here.

In the meantime, though, I figured out I can get my feeder line straight outside and directly to my antenna without putting a coaxial connection in between. With that part now figured out, I'm just a couple weeks away from stringing my new, longer random-wire antenna.
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