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What would you do 3 acres & some antenna wire?

That swaged / ferruled russian military (I think) masting is good and strong. Using several lengths of it here for a VHF vertically polarised Xyagi and also fixed into top of a tree to give an extra 18 feet of height above the foliage. Ed is right, its good stuff, strong and good value. I got mine from FN some years ago, but I have seen it on sale here in UK at rallies. Highly recommended if you can find it. External diameter is approx 40mm - maybe slightly more. Nice thick wall unlike most “fishing poles”. It can be made to fit inside aluminum pipe / scaffold etc by adding shrink sleeving to the outside to get a nice push fit and then bolting through in two places. Good stuff.

73 Phil

73 Phil

My reading of the issue with conductive masts in the centre of dipoles is that while it is undesirable from a purist’s viewpoint, it doesn’t really cause a big problem. The fields from the antenna, if symmetrical about the mast, would be equal and opposite in polarity.

My “temporary” home mast is a 6m steel pole. I have an outrigger offsetting the feedpoint for my 4 band fan dipole by about 40cm. The coax feed plugs into a balun and the antennas are all attached to the balun. A halyard running through a stainless steel sheave (and its nylon pulley) is attached to the outrigger and allows for antenna maintenance and mods without lowering the mast. The main mechanical drawback to this arrangement is that the coax feedline is hanging from the feedpoint (the balun actually) and cannot be strapped to the mast once the mast is up. The weight of the coax is partly supported by a rope harness attached to the feedpoint insulator, to take some strain off the coax connector, a PL259 in this case (one of the few I use).

Re 160m I read comments from the top band specialists saying that low dipoles (indeed any horizontal wire antenna including the loops) are very inefficient due to the high angle of radiation and the low inherent radiation resistance, which is largely ground loss resistance. They say that a loaded vertical is better for transmitting than any low dipole. I have not tried that myself, but I think it is a very credible claim.

We can read on this reflector of efforts to get an 80m dipole extended for 160m, the low signal reports received seem to support the claims about low dipoles.

Support for the effectiveness of loaded verticals comes from some VKs I know who have tried them, including Tony VK3CAT, Dale VK1DSH, Dimitris VK1SV/VK2COW, Peter VK3YE and others.

So while not saying the low dipole won’t work, I suggest if you want better performance other antennas not so affected by proximity to earth may be a better option. Perhaps not achievable in your initial setup to get a few bands working remotely.

Thanks for raising this subject, it is of interest to many city dwellers.

73 Andrew VK1DA/VK2UH

Hi Andrew,
this was the point I was also trying to make - in my comment to keep the wire away from the metal pole.

I think if James can easily get the metal mast from his mate, then put it up and try a F/G mast solution later when he can pick them up for a good price. James has said that he’s likely start with his trapped dipole in any case, so the Loop (or whatever is decided upon in the end) can be planned over time. Generally, any antenna is going to work better out in the countryside than in a metro area.

73 Ed.

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