Poor choice AFAIK. My understanding is that if the tower gets takes a heavy hit by lightning, the wire could vaporize and crack the concrete. Ken WA8JXM ______________________________________________
A low SWR does not indicate resonance. Resonance does not necessarily provide a low SWR. A true quarter wave resonant vertical over a perfect ground plane has a feed impedance of about 30 ohms and th
Gerald, I disagree. If a quarter wave vertical or ground plane is lengthened to about .28 wavelength, the radiation resistance raises to about 50 ohms and a 1:1 SWR. It is not resonant, but it has a
Okay, Gerald, I will agree that you and I are talking about different things. But most people talk about adjusting their antenna and saying it is resonant (or not) when they get a 1:1 SWR. As you hav
Paul, I think you forgot to differentiate between the actual SWR and what a meter may read ;-) Just because a meter says the SWR is 5:1, doesn't necessarily mean it is so. A meter at different points
You can download topo maps online that will give you as good as 10 ft intervals depending on how flat your terrain is. See http://store.usgs.gov/b2c_usgs/b2c/start/%28xcm=r3standardpitrex_prd%29/.do
Actually this setup is covered in this month's QST "The Doctor Is In" column with a couple of references to older QST articles. A center fed dipole with open wire or ladder line is a very good multi
Because it gives you the efficiency of a full half wave dipole on 80m. Ken WA8JXM _______________________________________________ _______________________________________________ TowerTalk mailing lis
I see it differently. When going significantly below a half wave, you are eliminating a significant portion of the high current portion of the radiator. The highest radiation currents flow in the cen
Steve, The issue is not about I^2R losses and feedline cannot compensate for missing antenna wire. It's the antenna wire that radiates, not a properly balanced feedline. How do you "increase the feed
You are trying to tell me that if I had an excellent matching network, I could use a 2m dipole on 80m and it would be just as effective? Sorry, I think you are confusing feed and matching losses and
The "cloudwarmer" function is more likely a result of the height rather than the length. There is nothing wrong with a "cloudwarmer" unless you are a DXer. A cloud warmer will probably outperform a d
I have trouble accepting that. We will have to agree to disagree. Ken WA8JXM _______________________________________________ _______________________________________________ TowerTalk mailing list Tow
Paul, THERE I agree with you because the high current portion (e.g. center portion of a dipole, or the "effective" quarter wave portion of a vertical) is used as a radiator. End loading works well be
What difference does it make, we don't put the matching network (lump) at the feed point (except people with remote tuners like the Icom AH-4). Most of us have a linear "matching network" of 30-100'
Sure. Check, the SWR across the band. Is it higher at 7.3, or 7.0? Is there a lower SWR in the middle? If it looks like the lowest SWR is below the band, then shorten the antenna by 6" and remeasure.
Many good ideas here. If you are really worried, put up some fence panels with the orange SMV triangles on it. (On second thought, forget the fence panels, just put up a couple of fence posts with th
SOMETIMES they break in the middle. Not always. I'll bet a guyed tower with a minimum base will fall intact if a guy wire fails. If you elect to live on a small lot, I can certainly understand regula
I have often wondered about that. Is stainless exempt from dissimilar metal galvanic action? Why not just use copper (with brass machine screws, nuts and washers)? Are there any drawbacks to that? Ke
You can take a couple of feet of 1/2" copper water pipe, flatten it with a hammer and drill all the holes you want through it for a lot less money than the DXE stainless steel plate. In my mind, copp