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+---- Thread: Hardline splicing (/showthread.php?tid=908)
Hardline splicing - Rob_Walker - 2023-01-22
That was a good article in the newsletter regarding hardline splicing. Thanks Tom.
I didn't get my Yagi up this past summer so my 1/2" Heliax sits in two pieces. I have an Andrews connector specifically for splicing hardline, and I also have a collection of "N" connectors with bulkhead connectors for joining them.
I was particularly interested in the newsletter article using copper tubing. I'm curious what one would use for a dielectric after the centre conductor was joined but before the 1/2" copper tubing was installed on the outside jacket?
What I like about this method is it would minimize the weak spot where the hardline might want to kink. Open to suggestions.
73 Rob
RE: Hardline splicing - Tom VA3TS - 2023-01-23
A dielectric such as RTV silicone or something similar. It would need to survive the heating due to soldering, but there is a high temp RTV that is red in colour for such applications. Another option is nothing at all. I used a copper foil tape to make a join on a piece of rg58...in my vehicle for the roof antennaa...still in use after 12 years...73
RE: Hardline splicing - Rob_Walker - 2023-01-23
I contacted Karl, the author of the article, and we got a bit of a dialog going on. If you go to the Groups IO forums where the repeater builders hang out, there are mixed opinions on the dielectric.
My inquiries said foam dielectric is 2 to 3 times better than air, but it didn't say say at what frequency. Karl uses air and has had no problems. I think the sure-fire test would be to connect a VNA and see if you get a bump down the line. My guess is you would get less of a performance or return loss issue with the copper tubing verses all the Andrews N connectors and couplers. Either way, the return loss would be so insignificant in my short run (<200') , it would not make a difference
I hope to keep you posted
By the way, 1/8" OD refrigerant copper tubing will take care or the centre conductor.
Cheers
73 Rob