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Old 25-May-2020, 6:26 PM   #1
bobsgarage
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Join Date: Mar 2016
Location: Beach Park IL
Posts: 292
1/4 Wave Matching Sections and Combining Antennas

Well, so far it's not a success story. Far from it I'd say. I have been reading all along the best way to combine antennas is simply not using a combiner /splitter. From what I understand, you're lucky to get anything out of combining the two antennas if you use a splitter to combine them. Well, to me that's just stupid.


So as far as I understand, the most common now it's things are in order to combine 2 antennas for gain, you must have several important features present.

#1. Both antennas must be exactly the same, from the same manufacturer, part number. Essentially the same production.

#2. Most coax cables must be the exact same length, the same kind for example : RG6 dual shield Etc... and should be the same manufacturer and part number. Might as well take it off the same spool.

#3. Both antennas must be mounted at the same height but can be stacked over each other with the proper distance or side by side, where the separation isn't a big deal.

#4. Both antennas need to be aimed at exactly the same target in order to make the gain.

#5. There's no point combining antennas for gain if you are going to have a lot of loss in the system. Combiners/splitters eat signal. So, this is where the quarter wave 50 ohm "matching" (stub) section comes in handy.

So here's my saga. Get a beer, some popcorn relax and read on.

So I did my research, talked to a few people on some other forums and found out that either RG 8 or RG58 can be used to create these matching sections. As longs as it's 50 ohm. A friend of mine who I met on this forum just happened to have a roll of foam filled RG8. StereoCraig has donated several lengths that I thought I would never need. Honestly for my new arrays, one VHF pair and one UHF pair I figured that would be enough. However it didn't turn out that way.

I had first read that quarter wave matching section for UHF made from RG 8 should be 10 inches. Including connectors. Okay. No problem, I butchered a combiner, got the cover off tore all the guts out and ran my two equal antenna leads into the sides stripped the RG 8 and somehow got it to slip into a RG 11 coax connector. (I drilled it). I then used some solder to join the three together inside the combiner. It was my first time so it took me sometime, but it seemingly turned out fine.

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Last edited by bobsgarage; 26-May-2020 at 7:12 PM.
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