Posted: 2/23/2012 12:50:16 PM EDT
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Been thinking of setting up a 160M loop for some time. Now that spring is on it's way, I'm thinking of getting one put up before the trees start grow leaves, and make it impossible.
Worth it? Found many different theories, plans, and ideas online. (coax, ladder line, balun, no balun, bare wire, insulated, etc). |
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Tower Climb/Antenna Hanger Club Boss is coming down tomorrow to complete site survey for my 160 Full Wave Loop.
From what everyone tells me, and I read on-line and in books it should do all I'd ever wish for.....Plan to feed with 4:1 Current Balun (less than 35' of coax feed). |
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Not sure I'd be able to do less than 35 feet of coax...but 50ft might be a closer estimates depending.
Safety issues notwithstanding, what's the closest you want to run parallel to a power line? I have kind of a crappy situation. there's a power line down the middle of the property. and another across the back yard. Photo: 
Red is power lines Blue is just a measure...nothing currently located there Green is my 160M G5RV |
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This is a very popular loop for 80 meters on up, takes up about the same length as an 80 m dipole.
http://web.archive.org/web/20080612065919/www.bloomington.in.us/~wh2t/Super+Loop+Antenna.htm But it sounds like you want a "Skywire Horizontal Loop" like this: http://www.donkeith.com/n4kc/article.php?p=12 |
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I have an 80m vertical delta loop up now and I used to run a 80m horizontal loop. I wish I could afford a 1000' roll of wire to put up a 160m horizonal loop because I love 'em and need something that loads better on that band. I fed my horizontal loop with 300 ohm twin lead and my current vertical loop is feed with homebrewed 600 ohm open wire feed. I folded the whole thing so the feed and antenna are one piece of wire with no breaks in the insulation. If you want to use it off of the fundamental frequency I reccomend using balanced line.
We need more info about the power line. Is it like a 1440 volt three phase type line or is it transformed down 220 volt that is only feeding you and yor neighbor? If it's a bundle of 220 you could be very close. If it's 3 phase power I would want to be at least 6 (and preferably 10) times the distance between the upper 3 phases and the ground "chaser" wire that's below away. |
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If you put a skywire loop up, and feed it with 600 ohm ladder line.....you'll never look back. That said, if the loop is just one big loop you need to get it up in the air as high as possible. The larger the area inside loop, the more efficent the antenna. You can also make a 'multi-turn' loop using two complete turns which effectively cuts the circumfrence in half. If you have an antenna coupler like an SG-230 or IC-4, you can even shrink the circumfrence smaller by using more turns. I had an 80 meter loop up about 40' fed with coax and an ugly balun at the connection point to the loop. It worked pretty well, even though I would have liked to have had it higher. At the time I had neither an SG-230 antenna coupler or the double L balanced line tuner that I do now....nor do I still have the loop.  If I had the lot you have, I'd have a 160 meter loop up as high in the trees as possible. I'd make it as circular as possible, as far behind the powerline as possible, and I'd feed it with 600 ohm ladder line. As long as the ladder line crosses under the power lines at a 90 degree angle, you shouldn't have any issues....or I'd do the same only attaching the ends of the loop to an antenna coupler and feed it with coax. You could even bury the coax out to the antenna. Keep us posted. |
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Quoted:
If I had the lot you have, I'd have a 160 meter loop up as high in the trees as possible. I'd make it as circular as possible, as far behind the powerline as possible, and I'd feed it with 600 ohm ladder line. As long as the ladder line crosses under the power lines at a 90 degree angle, you shouldn't have any issues....or I'd do the same only attaching the ends of the loop to an antenna coupler and feed it with coax. You could even bury the coax out to the antenna. Keep us posted. Any maximum lengths with regards to running the 600 ohm ladder line? We'd be looking at about 150-ish feet to get it under the power lines. Could also do a run of coax until I cross the power lines, then a 4:1 balun to ladder, up to the feedpoint. The area directly west of the house is a bit too small to safely run the 160M loop. Reminds me, I need to stock up on 5.56 blanks. Launching a dummy grenade with monofilament up over a tree might be a bit more accurate than a slingshot. More fun too ;-) |
The M200 blanks are WAY too powerful for my modified Isreali practice grenade. The M200's will send it well over 200ft up. I have since loaded my own blanks using 2 grains of Bullseye which sends the PG up about 100ft.
Definately more acurate than a slingshot, and a heck of alot more fun! |
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The M200 blanks are WAY too powerful for my modified Isreali practice grenade. The M200's will send it well over 200ft up. I have since loaded my own blanks using 2 grains of Bullseye which sends the PG up about 100ft. http://i46.photobucket.com/albums/f110/vassili67/FD%202010/DSCN5675.jpg Definately more acurate than a slingshot, and a heck of alot more fun! any crimp?wax plug? Or just 2 grains? I could load my own...that's no problem. My grenade is a bit different too...larger head, black, will have to take pics if I find it later. |
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Any maximum lengths with regards to running the 600 ohm ladder line? Nope, that's the beauty of open wire feeder; nearly zero loss over very long runs (for a run that length you are probably looking at somewhere in the neighborhood of 0.1 dB on 160m but I don't have my charts to check at this moment). If you really want to know how awesome ladder line is for multiband antennas compare the loss of a coax run to a ladder line run when the swr is 10:1 
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Quoted:
The M200 blanks are WAY too powerful for my modified Isreali practice grenade. The M200's will send it well over 200ft up. I have since loaded my own blanks using 2 grains of Bullseye which sends the PG up about 100ft. http://i46.photobucket.com/albums/f110/vassili67/FD%202010/DSCN5675.jpg Definately more acurate than a slingshot, and a heck of alot more fun! I just can't imagine why I haven't seen this mentioned on here before. Where have you been hiding this??? More details please! |
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Quoted:
Quoted:
The M200 blanks are WAY too powerful for my modified Isreali practice grenade. The M200's will send it well over 200ft up. I have since loaded my own blanks using 2 grains of Bullseye which sends the PG up about 100ft. http://i46.photobucket.com/albums/f110/vassili67/FD%202010/DSCN5675.jpg Definately more acurate than a slingshot, and a heck of alot more fun! I just can't imagine why I haven't seen this mentioned on here before. Where have you been hiding this??? More details please! You think that's awesome, about 5 years back the surplus market was flooded with grappeling hook/line launching kits for the M16. They were pretty cheap at the time. Now they are over $100 if you can find them. 
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Now I want a grappling hook. Mine is a modified Isreali practice grenade. IIRC I bought it from Sarco or Numrich 5 or 6 years ago for decoration. Sitting here a few days before Field Day 2009? wishing I hadn't left my slingshot/reel combo up on Four Peaks the week prior, I spied the PG sitting up on the shelf. After doing some research on recoil etc.. I cut the nearly one pound rubber head off of it and decided to use it as a line launcher. The local FFL had some M200 blanks and away I went. I drilled a hole in one of the fins to attach the line to. A 12 inch steel fishing leader is used as the muzzle blast would most likely sever monofiliment.
Funny Field Day story. Ok, we get up to the FD site. It's at 7200ft elevation and has tall pines, like 100ft tall. My buddies were out with their slingshot shooting up lines and I walk up with the M4 and the PG on the muzzle and say "..meh, I'm going to use this..". They say OMG! that's cool! Have you fired it yet? I said "no, I haven't, but here goes!". Now at this point, I hadn't painted the PG yet so it was OD, keep this in mind. I slipped a M200 into the chamber and dropped the bolt. I reared back at about an 80 degree angle and let her fly...and fly...and fly. This thing went up at least 200 feet, maybe more. We lost sight of it and it seemed it took forever to come down. It landed about 75 yards from where we were standing...but it took all of us 45 minutes to find it....then 5 minutes to paint it. 
I use a small tuft of cotton in the neck to keep the powder in. 2g is a very light load and some might argue it may not fire due to low powder volume in a large case, but remember, these will be fired at a steep up angle so the powder will sit on the flash hole. |