Posted: 2/26/2009 3:07:02 PM EDT
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80 X 80
30 foot off the ground, supported at the corners. fed with ladder line to the tuner. I am going to try and get it up as soon as the wind dies down here, hopefully this weekend. Waste of effort, or you think it will work well? Kind of disappointed in the Alpha Delta DX-CC I have in an inverted V. Gonna hit up Southerlands tomorrow and see what kind of wire they have. I have the ladder line already. |
| Should work. As any antenns goes, some bands will be better then others. Without doing any modeling, should be pretty good on 80m, 40m.....20m..not too sure. It'll work but how well is the question, Plse post your findings when it's up. I'm curious your results. Maybe we can do a on air test. MT to TX is usually pretty good. |
Should work well. Heck mine is all but on the ground right now and still works great 
You might want to trim it though. If you have an MFJ or similar antenna analyzer I'd recommend you trim for resonance around 3.6MHz. I've run models on loops and it you don't have the harmonics in the right places it will be a lot more work for the tuner and it might not get all of the higher bands. Try it out first! and then if doesn't tune up through 10m trim a bit. |
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I had a skyloop antenna up for sometime at my old house and it was the shiz!! They have a very low noise floor and work as well as anything else I ever tried including di-poles. My only regret was that I didn't have a balanced line tuner at the time. Ladder line iz da shiz too!! Figure 1005 divided by your lowest frequency for the length of the loop. Mine was cut for 4 Mhz MARS freqs so it was 1005 / 4.0 = 251.20 feet total, or about 63 feet per side. Mine was coax fed into the corner with a choke. I used 18 gauge chandalier wire from Home Depot as it was $40 bucks for 500 feet, but that was several years ago. You may want to experiment with both feeding it at the corner vs feeding it midway along one side. Apparently it makes a difference. 30' off the ground is OK. Higher is better, but I know a guy who ran a loop at 8 feet and claimed QSOs into Europe with it. There is a bit of stuff on 'skywire loops' on the net, just google it. Have fun, you're gonna love the antenna!!  '73 |
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Quoted:
Should work well. Heck mine is all but on the ground right now and still works great
You might want to trim it though. If you have an MFJ or similar antenna analyzer I'd recommend you trim for resonance around 3.6MHz. I've run models on loops and it you don't have the harmonics in the right places it will be a lot more work for the tuner and it might not get all of the higher bands. Try it out first! and then if doesn't tune up through 10m trim a bit. +1 |
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Thanks for the input guys. I have all the stuff together and I have an MFJ 259B analyzer. I just need to grab some T posts from TSC and get the masts and wire up. I work 12 hr days, 7 days a week, so might take me a few more days to get it all up.
Planning on just letting the wire "float" on the 3 corners and a pulley into the one corner to feed it, with 300 ohm ladder line. I have a 4:1 balun I can put at the tuner. Radio-Icom IC7000 Tuner-LDG AT7000 The balun came with the 43' Zero-Five vertical that is going on the roof when I get done with this loop. Hopefully I can get this stuff done this weekend. Might not get it all done, but we'll see Patrick |
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Quoted: Keep us posted! Thanks for the input guys. I have all the stuff together and I have an MFJ 259B analyzer. I just need to grab some T posts from TSC and get the masts and wire up. I work 12 hr days, 7 days a week, so might take me a few more days to get it all up. Planning on just letting the wire "float" on the 3 corners and a pulley into the one corner to feed it, with 300 ohm ladder line. I have a 4:1 balun I can put at the tuner. Radio-Icom IC7000 Tuner-LDG AT7000 The balun came with the 43' Zero-Five vertical that is going on the roof when I get done with this loop. Hopefully I can get this stuff done this weekend. Might not get it all done, but we'll see Patrick  |
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Man,
I still haven't gotten it put up. I was hoping to get it up this week after the time change, since I now have a couple hours of daylight when I get home. But things keep coming up. GF comes over to visit, stupid crap like that. And yesterday we had a front move in and rain and cold. I got the poles up, just need to thread the wire up and penetrate the house. Hopefully I can get it done this weekend. Been raining off and on all day today. Might be dry enough to get on the roof this afternoon. I dunno yet. Real life sucks. I'll let you guys know as soon as I get it up. This weekend unless the world stops turning. Or the GF offers to sleep with me again. You know |
Antennas work better when they are installed in inclement weather.  I'm in DFW so I'm getting the same wet/cold. Just had a thought. When you hang your wire, be sure and include some type of 'strain-relief'. On mine, I ran the wire through some 6 inch long pieces of 1/2 inch pvc pipe for insulators, and used heavy rubber bunji cords to attach them to the masts. This allowed the wire to expand and contract due to the temperature, ice, and wind without stressing the wire. Some folks attach one corner of their loop to a rope which runs through a pulley and has a small weight attached to the other end. It keeps the wire tight, but allows it some flexability for temps and wind. Two corners would even be better. IM me when you get it put up and we'll try it out. '73 |
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I talked to several of the net and asst net controls of a net in my area, and they are using:
http://www.bloomington.in.us/~wh2t/Super%20Loop%20Antenna.htm 
http://larc.hamgate.net/SuperLoop.htm 
"The "trick" to the Superloop is the 30' length of ladder line hanging down from the center insulator. This length has been tuned so that appears to be a open-circuit stub on 40 meters; thus the antenna becomes two full-wave wires (at 40 meters) and is commonly referred to as the Bi-Square antenna. On 80 meters, it appears to be a short and the antenna becomes a single wave vertical loop. This happens automatically and no switching is involved. "A special balun is provided which gives a match between the 50 ohm coax lead-in and the higher resistance of the loop. For best matching, a 1/2 wavelength coax is recommended (e.g. 99' of RG-8X); however mine is about 70 feet into my diff-T tuner and the SWR < 2 points are 3495 to 3787 but the short coax gives a minimum on 40 of 2.05 at 7090 KHz. If you need to run without a tuner, close attention to the coax length will help. The balun is the typical ferrite rod in a PVC pipe with foaming urethane inside. This has the effect of heat insulating; mine works fine on 500 RTTY watts contesting, but real high power may be a problem on RTTY; but those guys all have beams, right?" |
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This is going to be a horizontal loop.
IF I can ever get the fricking thing up. I been sitting at work all day. Pretty, sun shining. Still kinda chilly, but nothing a light jacket can't handle. I have maybe 1.5 hours of work to finish on it. Mostly just get the wire up and penetrate the house and fish it down the wall. I get home and the rain comes a flood. Texas weather sucks sometime. At least tomorrow the front will be over and it shows 10% chance of rain. So hopefully I can get this up tomorrow. With the time change, I should have the time after I get off. 
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