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#1
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Well, I found a reference to a 10-40 meter flagpole antenna for HOAs
that don't like antennas. But they all require radials as long as the vertical height of the antenna, and my minuscule lot just won't be large enough for radials of any significant size. Is there any other option for a vertical antenna for 10-40 meters that doesn't require radials? In another location, I used a random length dipole under the eves of the house with a Johnson Matchbox tuner with good results. And maybe, I can do the same with a random length dipole in the attic, but the flagpole is an intriguing option. And I was always concerned about the radiation in the house from the antenna and from the ladder line lead. In fact, the irrigation solenoid valves used to open when I transmitted. jimbo |
#2
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Well I may be wrong here but my understanding is the wires on the ground are
a counterpoise and need not be tuned. As they are coupling to the earth. But it may take numerous wires for the counterpoise. Ground conductivity enters into this as well. Radials on an elevated antenna on the other hand should be tuned. Just four radials on an elevated antenna will do well. I had a ground mounted vertical and just sprinkled lots of wires thither and yon as best I could to fit in the lot and the antenna tuned fine. Try it and see the results. You could try a half wave vertical -- no radials required but now you have an impedance mathing problem. Some Cushcraft antennas use a half wave end fed scheme, the black box at the feed point is matching unit. -- Caveat Lector (Reader Beware) "jimbo" wrote in message ups.com... Well, I found a reference to a 10-40 meter flagpole antenna for HOAs that don't like antennas. But they all require radials as long as the vertical height of the antenna, and my minuscule lot just won't be large enough for radials of any significant size. Is there any other option for a vertical antenna for 10-40 meters that doesn't require radials? In another location, I used a random length dipole under the eves of the house with a Johnson Matchbox tuner with good results. And maybe, I can do the same with a random length dipole in the attic, but the flagpole is an intriguing option. And I was always concerned about the radiation in the house from the antenna and from the ladder line lead. In fact, the irrigation solenoid valves used to open when I transmitted. jimbo |
#3
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"jimbo" wrote in message
ups.com... Well, I found a reference to a 10-40 meter flagpole antenna for HOAs that don't like antennas. But they all require radials as long as the vertical height of the antenna, and my minuscule lot just won't be large enough for radials of any significant size. Is there any other option for a vertical antenna for 10-40 meters that doesn't require radials? In another location, I used a random length dipole under the eves of the house with a Johnson Matchbox tuner with good results. And maybe, I can do the same with a random length dipole in the attic, but the flagpole is an intriguing option. And I was always concerned about the radiation in the house from the antenna and from the ladder line lead. In fact, the irrigation solenoid valves used to open when I transmitted. jimbo Jim: I suggest that you do not get carried away with not having room for "full length" radials. I've read some interesting research (I will find the references if you are interested) on this. It appears that radials as short as 0.1 wavelength are quite effective. Are longer ones better. Yes. It is also better to be transmitting in the middle of the ocean. ![]() be young, rich, and handsome, too. Seriously, lay down whatever radial pattern you can. The more the better, the longer the better, but you will surprised how quickly (in both cases) it becomes a matter of quickly diminishing returns. A friend of mine lives in a restricted community in Southern Cal. He got permission to put up a flag pole, so he and (I was visiting at the time) went out on a Sunday afternoon when everyone could see us and set-up his flagpole, raised the U.S. Flag, etc. Then, about 3 a.m. we went back out and buried 4 radials and a coax feedline. There are not enough radials and they are too short. However, he has no problem working the entire Pacific Rim with 100w. Paul AB0SI |
#4
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![]() "pfriedmanNoSpam" wrote in message ... "jimbo" wrote in message ups.com... Well, I found a reference to a 10-40 meter flagpole antenna for HOAs that don't like antennas. But they all require radials as long as the vertical height of the antenna, and my minuscule lot just won't be large enough for radials of any significant size. Is there any other option for a vertical antenna for 10-40 meters that doesn't require radials? In another location, I used a random length dipole under the eves of the house with a Johnson Matchbox tuner with good results. And maybe, I can do the same with a random length dipole in the attic, but the flagpole is an intriguing option. And I was always concerned about the radiation in the house from the antenna and from the ladder line lead. In fact, the irrigation solenoid valves used to open when I transmitted. jimbo Jim: I suggest that you do not get carried away with not having room for "full length" radials. I've read some interesting research (I will find the references if you are interested) on this. It appears that radials as short as 0.1 wavelength are quite effective. Are longer ones better. Yes. It is also better to be transmitting in the middle of the ocean. ![]() to be young, rich, and handsome, too. Seriously, lay down whatever radial pattern you can. The more the better, the longer the better, but you will surprised how quickly (in both cases) it becomes a matter of quickly diminishing returns. A friend of mine lives in a restricted community in Southern Cal. He got permission to put up a flag pole, so he and (I was visiting at the time) went out on a Sunday afternoon when everyone could see us and set-up his flagpole, raised the U.S. Flag, etc. Then, about 3 a.m. we went back out and buried 4 radials and a coax feedline. There are not enough radials and they are too short. However, he has no problem working the entire Pacific Rim with 100w. Paul AB0SI I live in the sticks, so I can put up whatever I please. But it seems to me a metal roof with a Fluidmotion SmallIR with a flag on the roof would ROCK from 20 on up. Of course folks who wanted just a flag have been screwed by homeowner's associations. OTOH a nice copper gutter can get the job done. Or just build a kick-ass mobile rig. BTW Why do people even get involved with such BS, anyway? I didn't make you live there. 73 H. NQ5H |
#5
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jimbo wrote:
Well, I found a reference to a 10-40 meter flagpole antenna for HOAs that don't like antennas. But they all require radials as long as the vertical height of the antenna, and my minuscule lot just won't be large enough for radials of any significant size. Is there any other option for a vertical antenna for 10-40 meters that doesn't require radials? In another location, I used a random length dipole under the eves of the house with a Johnson Matchbox tuner with good results. And maybe, I can do the same with a random length dipole in the attic, but the flagpole is an intriguing option. And I was always concerned about the radiation in the house from the antenna and from the ladder line lead. In fact, the irrigation solenoid valves used to open when I transmitted. jimbo Hi Jimbo, All the responses you have received so far are good, But one other possibility is to install a fiberglass flag pole with a diameter big enough to accomodate and R-7 or similar no ground vertical. A freind here did that and it worked quite well. 73 Dave ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
#6
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![]() Long, shallow buried radials are by no means a necessity. Your dry, painted timber flag-pole, with a plastic insulated antenna wire running down it, can be located alongside a wall of your house or at the end, side or middle of the garden. The soil should not be very dry and sandy but should be capable of growing common-or-garden flowers, shrubs or lawn grass. To improve the soil dig in compost or horse manure. A light sprinkling of copper sulphate won't do any harm except perhaps to the plants. Lay a dozen or a score of 10-gauge or thicker radials, as long as you can and in as many directions as you can from the base of the pole. They will be useful even if only 2, 3 or 4 feet long. Use bare copper wire, at a depth of a few inches in well compacted, trodden-down soil. Lay paving slabs on top if you like. For multi-band use you will need an automatic tuner such as an Icom AH-4 located near the base of the pole. If the pole is mounted on a wall of the house the tuner can be located indoors in the dry. ( My AH-4 is mounted on the inside wall of the kitchen under the kitchen sink. It is also conveniently near to the main incoming water pipe which serves as my best of 7 short radials. The earthing loss resistance is only 6 ohms.) The AH-4 ( no electric motors - a set of relays) easily tunes a 32-feet unloaded vertical wire down to the 160 meter band. It is primarily intended for use in vehicles. You don't HAVE to have an automatic tuner at the base of the antenna. You can use a home brew L and C matching network on an indoors window ledge by extending the vertical antenna wire sideways, above ground level, through the side of a downstairs window frame. The wire is then X feet longer. There are a number of workable variations on the tune. If you like amusing yourself with numbers, download in a few seconds program ENDFEED from website below and run immediately. ---- .................................................. .......... Regards from Reg, G4FGQ For Free Radio Design Software go to http://www.btinternet.com/~g4fgq.regp .................................................. .......... |
#7
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Your dry, painted timber flag-pole, with a plastic insulated antenna wire
running down it, can be located alongside a wall of your house or at the end, side or middle of the garden. One common house-building style around here (California) uses a building frame of 2-by-4 or 2-by-6 wood, with an outer layer consisting of stucco which incorporates a galvanized-steel "chicken wire" mesh. I'd encourage keeping HF vertical antennas well clear of any walls made in this fashion. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
#8
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I have had to deal with the same situation and I found that ground moisture
plays a big part in making the ground radials work, no matter the length. I picked up a couple 50 pound bags of rock salt, sprinkled it in and around the radials before covering them up and it worked like a charm. Don't be stingy with the salt... and it didn't even kill the grass. The longer the rock salt stays in the ground the better the antenna worked. A good watering down of the area is enough to start the process. If you live in a dry climate an occasional watering also helps. Sure the salt will corrode the wire but before that happened I'll probably be an SK. That's my 2 cents worth but it worked for me. I've got up inverted Vees at one home now and can really appreciate the real estate. I'm on the east coast (VA) and have worked VK & ZL with 100 watts on SSB 75 and 40 meters. 73, Ken "jimbo" wrote in message ups.com... Well, I found a reference to a 10-40 meter flagpole antenna for HOAs that don't like antennas. But they all require radials as long as the vertical height of the antenna, and my minuscule lot just won't be large enough for radials of any significant size. Is there any other option for a vertical antenna for 10-40 meters that doesn't require radials? In another location, I used a random length dipole under the eves of the house with a Johnson Matchbox tuner with good results. And maybe, I can do the same with a random length dipole in the attic, but the flagpole is an intriguing option. And I was always concerned about the radiation in the house from the antenna and from the ladder line lead. In fact, the irrigation solenoid valves used to open when I transmitted. jimbo |
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