Posted: 12/9/2010 2:45:16 PM EDT
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I'm thinking about building one of the 80m superloops as described in another thread. Unfortunately, I've only got 1 tree that's conveniently located. I need another one about 110' or so away, and it ain't there, or there several others in the way. Any suggestions for a cheap, semi-permanent homebrewed support for one leg of a wire antenna that'll reach 35-40' up in the air? Thanks, -Slice |
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At a lot of hamfests there are guys selling surplus military antenna masts. You might be able to find them at your local surplus shop.
The metal ones, while not ideal for supporting a wire antenna, are more likely to stay up. The plastic ones apparently aren't entirely UV stable and will become brittle after a time. You might be able to combat that with some spray paint. ETA: something like this might work |
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12 Military Fibreglass Mast Support Poles Ham Radio 48"
$7.50 + 20.97 shipping = $28.47 Total Approximate Dimensions 48" long 1-3/4 inches in diameter 1/4 inch thick wall 45 feet in length if joined together 2 1/4 pounds per pole |
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I have a collapsible pole like that for supporting my 20m QRP inverted v - too flexible to support a loop. The fiberglass cammo supports are a better bet, but you'll still need to back guy them. |
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Quoted:
I have a collapsible pole like that for supporting my 20m QRP inverted v - too flexible to support a loop. The fiberglass cammo supports are a better bet, but you'll still need to back guy them. Even if you guy it opposite the anchor point? |
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Quoted:
12 Military Fibreglass Mast Support Poles Ham Radio 48" $7.50 + 20.97 shipping = $28.47 Total Approximate Dimensions 48" long 1-3/4 inches in diameter 1/4 inch thick wall 45 feet in length if joined together 2 1/4 pounds per pole That's my plan to make my loop a little bigger. I'm lucky to have 3 tall trees, but I need one more corner to cover the biggest area possible. The old man that built this place built a clothesline with poles made of angle iron doubled up and set in footers. I'm going to clamp those military masts to one of those poles and that'll make my new corner. |
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Quoted:
Rohn makes a telescoping "push up" mast that is about 40' high, all galvanized, with guy rings. Yeah, I know. I just bought 600 bucks worth of them. 
The problem with push up poles... The freight is a killer. I bought 2 of them for the super loop, and one for a 6m antenna. |
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Quoted: Quoted: 12 Military Fibreglass Mast Support Poles Ham Radio 48" $7.50 + 20.97 shipping = $28.47 Total Approximate Dimensions 48" long 1-3/4 inches in diameter 1/4 inch thick wall 45 feet in length if joined together 2 1/4 pounds per pole That's my plan to make my loop a little bigger. I'm lucky to have 3 tall trees, but I need one more corner to cover the biggest area possible. The old man that built this place built a clothesline with poles made of angle iron doubled up and set in footers. I'm going to clamp those military masts to one of those poles and that'll make my new corner. Those poles are surplus camo suport system poles. They work ok, however, over about 16 feet you need guys. I had an 80 meter loop up between 4 masts of 40' using them. Several years ago I bought 12 dozen new in the box css kits surplus for 90 cents per kit, and resold them for antenna support pole kits. Each kit had the poles, stakes, batten spreaders, batten nuts, and a dandy rubberized canvas duffle bag to carry it all in. These were still in the factory boxes, unused. I sold them all on Ebay for $60 a kit + shipping. $59.10 profit each, less expenses for renting a truck to go fetch them all.  At the top of each mast I used on my loop, I put a pulley on a hog-ring and attached/hoisted the antenna using a flagpole-type lanyard running through the pulleys. Worked pretty well. Just bear in mind that it takes several people to get one up without breaking it. You need a couple pepole to help raise it by pulling on the guy lines. With 40' you need 2 guy rings, one at the top, and one about midway up. Raising a 40 mast out of these poles is really a 4 man job and is time intensive getting everthing laid out on the ground before raising it. With 3 guy lines per mast at 2 different hights, thats 6 lines laying out, plus the lanyard line. Sounds easy until you start to raise it.  Once they're up, and all the guy lines adjusted and staked out...they'll stand up to 70mph winds. Have fun! |
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Quoted:
Quoted:
Rohn makes a telescoping "push up" mast that is about 40' high, all galvanized, with guy rings. Yeah, I know. I just bought 600 bucks worth of them.
The problem with push up poles... The freight is a killer. I bought 2 of them for the super loop, and one for a 6m antenna. I paid $50 at a hamfest for mine. No rust, a little shopworn, but good condition. |
| pcsutton, the fiberglass mast sections are very strong in the vertical direction, it is the tenons that break with sideways forces. I've found the best way is not to try to lift the assembled mast Iwo Jima style, but to assemble a few with the guy rings and ropes (or guy wires... since the wire and parachute cord are my actual antenna) and hold vertically with others controlling the guys. Then lift it vertically, place another section underneath. Rinse, repeat, until desired height is obtained. This is then lifted and set on the support, whether the tripod or a swivel base. |
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Quoted: pcsutton, the fiberglass mast sections are very strong in the vertical direction, it is the tenons that break with sideways forces. I've found the best way is not to try to lift the assembled mast Iwo Jima style, but to assemble a few with the guy rings and ropes (or guy wires... since the wire and parachute cord are my actual antenna) and hold vertically with others controlling the guys. Then lift it vertically, place another section underneath. Rinse, repeat, until desired height is obtained. This is then lifted and set on the support, whether the tripod or a swivel base. That would work better.
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| I saw a thing on a ham's website where he called up the power company and asked how much to put in a utility pole. They quoted him a price... pole, labor, and all, they came out and did it. He said, "I'll take four." And that holds up his loop. Of course, this was out in the country behind a farmhouse. |
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Yep it is how I do mine , I can do it by myself but it takes a little bit of coordination , no wind and some luck . Quoted: Quoted: pcsutton, the fiberglass mast sections are very strong in the vertical direction, it is the tenons that break with sideways forces. I've found the best way is not to try to lift the assembled mast Iwo Jima style, but to assemble a few with the guy rings and ropes (or guy wires... since the wire and parachute cord are my actual antenna) and hold vertically with others controlling the guys. Then lift it vertically, place another section underneath. Rinse, repeat, until desired height is obtained. This is then lifted and set on the support, whether the tripod or a swivel base. That would work better. |
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Quoted:
I've seen places that sell surplused/used "telephone poles". A hole auger rental and you would be business. Just a wild idea... If I could find a place like that cheap enough, it would be rhombic time. ETA: Finally, Finally, my push up poles showed up on the truck today. This weekend, come hell or high water, the 80m super loop is going up. Look for the 80m super loop thread with AAR coming soon to a ham forum near you. |