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« on: July 16, 2013, 10:02:10 AM »
My loop is basically 300 feet of #14 house wire (black, but RF is color blind) and it is strung between 7 trees in almost a triangular shape. Why 7 trees, you ask? Because that's where 300 feet of wire would fit between. Altitude varies but is about 40 feet up. That's as far as I could reach with a borrowed ladder.
It is insulated using ceramic dogbone insulators and UV proof cords in each tree. The trees are tall so I felt that no 2 of them would swing in opposite directions at any one time. So far, I have been correct.
It is fed with about 50 feet of 450 ohm window line from the middle of one of the longer sections directly to a Tucker T-3000 antenna matching box with an adequate balun inside to handle the balanced load. It will tune SWR down to 1:1 on all bands, 80 through 10 and I may try it on 160.
Loops are notoriously quiet, noise-wise. Much less static and local QRN than other antennas I have used here.
It really works well on the Monday Night 20 Meter AM Net too.
I also have a 100 foot doublet, a G5RV in earlier life, but without the hokey twin lead and coax, fed with more 450 ohm window line to an MFJ Differential T Tuner in Studio B, a Johnson Viking II and NC-300. But an HQ-170 is in the works to replace that 300. I do have a second NC-300 as backup on the shelf.
This doublet is actually inside the perimeter of the loop, so there's no telling what kind of interaction is happening. All I know is both antennas work very well.