Posted: 11/4/2009 3:58:55 AM EDT
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Putting up my first antenna that uses ladder line. I remember some of the basics (don't run near metal, etc), but is there a good FAQ document of some sort?
I'm putting up a 160M G5RV. It's got 61 feet of ladder line, and I know it won't all be off the ground (probably mounting 25-35 feet off the ground). What's the best way to handle it? |
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What are your questions? We can start a FAQ :)
It shouldn't lay on the ground. Most people mount it to poles and run it paralleling the ground, cheapo fiberglass electric fence poles and zip ties should work. As far as proximity to metal and such stay away AT LEAST 1x the separtation distance of the wire, 2x is better and 3x+ is preferred. I think a lot of people aim for 6x but not always practical... Hope that helped some. Regards, Bill |
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What about looping over itself?
I've got 60 some feet...what about letting as much hang down as can, then feeding it back up along itself, and down? Im guessing that won't work well....but it was worth a thought. I guess the biggest question is what to do with the extra, if running it in the air or on standoffs is not an option. Coiling is bad too, right? |
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Yeah, you wouldn't want to coil it up or double it back on itself. It isn't shielded like coax so there will be interaction in close proximity of it.
I would say the best thing is to chop off any excess. You could run it directly to the tuner in your shack (preferred) or cut it, put in a balun and run coax back to the shack. |
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It's a G5RV style antenna I *gulp* ordered. Didn't have the time to fool around experimenting on this one. From what i've read, they require a set amount of ladder line, then a set amount of coax behind that.
I guess there's always trial and error, but with winter coming, i'd rather get it up and be done. |
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Measure the SWR for all bands and see how it tunes up. Chop it off about 3 feet at a time and measure the SWR. You can always add some back. I ran into a big problem trying to run ladder line into my RV. I screwed around with chokes, a balun, then I finally figured it out. I took 2 paralell pieces of coax about 8 feet long and went from my tuner to the ladder line. I used the center conductor of each leg. At the antenna end of the coaxes, I soldered the shielding braids together. On the tuner end I soldered a strand of 16 gauge to the braids and ran it to my ground bus. Viola...no more RF in the shack problems. Works like a charm. Ladder line is the ONLY way to feed a dipole...the other ways pale by comparison. Have fun! |
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Quoted: It's a G5RV style antenna I *gulp* ordered. Didn't have the time to fool around experimenting on this one. From what i've read, they require a set amount of ladder line, then a set amount of coax behind that. I guess there's always trial and error, but with winter coming, i'd rather get it up and be done. You do have a balanced line antenna tuner? |
| I bought a 204ft. G5Rv from Antennasmore.com it also has 61ft of ladder line. When stung up at about 35ft I still had about 26 ft that I just hung a few feet off the ground in tree branches in no particular fashion. I used a 100ft piece of 9913 type coax to connect it to the house. It has worked great on all the bands, 6 meters through 160, for nearly 4 years now, wlth a LDG pro 100 autotuner. |
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Quoted:
I bought a 204ft. G5Rv from Antennasmore.com it also has 61ft of ladder line. When stung up at about 35ft I still had about 26 ft that I just hung a few feet off the ground in tree branches in no particular fashion. I used a 100ft piece of 9913 type coax to connect it to the house. It has worked great on all the bands, 6 meters through 160, for nearly 4 years now, wlth a LDG pro 100 autotuner. Awesome. I could most likely get away with that. I'll be using an 857D with an LDG Z11-Pro. |
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If you've got that much extra why not just bring it right into the shack?
I've got a Cobra Ultralite Senior up at a dizzying 25'. It comes with a boatload of ladder line. I was able to arrange it so that the antenna goes from tree to tree across the backyard parallel with the back of the house. I aligned the middle of the antenna with the ladder line entry point in my basement. The ladder line comes straight off at right angles from the antenna towards the entry point. I have a about 15' of extra which is in a loose loop held up off the ground by a piece of 550 cord attached to the side of the house. At the entry point it goes through one of these: http://www.iceradioproducts.com/impulse1.html#2. Then it comes right into my shack and into my MFJ-993B tuner. No lossy coax! Keep it at least a foot off the ground. Don't cut it (most antennas that need ladder line need it for a reason). Right angles to the antenna for at least 1/4 wavelength. Loose loops, no coils. 3-6 inches away from metal. Cross metal at right angles. For an entry point simple drill two holes a ladder line width apart. Put in two threaded brass rods or long screws with heads cut off. Cut and terminate the ladder line with ring terminals. Double nut the ring terminals onto the brass rod inside and outside. |
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There is plenty of extra ladder line, but not enought to make it to the shack. The shack is at one end of the antenna, due to power lines and buildings. I'll have to run the ladder line down and over, and run parallel to the antenna to get it back to the shack.
Red = Power lines Green = Proposed antenna locations Circles= approximate trees Barn has metal roof. Pumphouse has old windmill tower on top. I am leaning towards attaching from the top of windmill tower, to a tree out past the barn. 
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