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#1
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i live in a neighborhood where the sight of a half-wave dipole would
cause a riot. however, a portion of my property is heavily wooded. i could easily hide even a 160m half-wave among the branches and leaves, leaving it invisible. is this practical? risky? caveat: i'm still studying for my technician's license so go easy on me :-). /mark |
#2
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I live in the forest, and use a couple of resonant dipoles hiding in the
trees. I have no problems at all. Once, during our ice storm, one of them came down when a tree broke off and fell. SWR is fine, and get good signal reports. Go for it. -- Mike-K5VSE Formerly WB6VSE, Senior Tech, Amateur Division, SBE/Linear Systems Watsonville, CA All out going Email, scanned with Norton Anti-Virus 2004 "Radios That Glow in the Dark" "3922 khz". |
#3
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K5VSE wrote:
I live in the forest, and use a couple of resonant dipoles hiding in the trees. I have no problems at all. Once, during our ice storm, one of them came down when a tree broke off and fell. SWR is fine, and get good signal reports. Go for it. Only caviet-- You need at least a general for 30 MHz, or below, but the absorbsion of rf at those freqs is minimal, tho the HEIGHT, at lower freqs for a good pattern (for long distance) might be a problem. But , say on 80-40 even at around 20 foot elevation, can work reliably several hundred miles! 20 and up meters shouldn't present much of a problem, and at 6 and 2 meters yagi be best bet, but relatively small size. Have fun- Jim NN7K |
#4
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![]() "Mark T. Kennedy" wrote in message ... i live in a neighborhood where the sight of a half-wave dipole would cause a riot. however, a portion of my property is heavily wooded. i could easily hide even a 160m half-wave among the branches and leaves, leaving it invisible. is this practical? risky? caveat: i'm still studying for my technician's license so go easy on me :-). /mark I have several wire antennas strung between trees, and found that even #14 or #16 wire with black or blue insulation at 50 feet is invisible against the trees, and almost invisible when viewed against the sky. What sticks out is the feedline, if it is hanging in the clear. You want that coming down next to a tree. You really don't want contact between the wire and branches. However, my 75m antenna goes through branches at one point, and it seems to be OK. Stay away from white, yellow, or red insulation. Tam/WB2TT |
#5
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K5VSE wrote:
I live in the forest, and use a couple of resonant dipoles hiding in the trees. I have no problems at all. Once, during our ice storm, one of them came down when a tree broke off and fell. Please allow me to apologize in advance, but I can't resist asking: "If a dipole falls in a forest and there's no one there to hear it, does it make a sound?" 73, John NU3E :-) |
#6
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Bill Turner wrote:
The voltage at the ends of a half wave dipole can reach thousands of volts even with relatively low power. Trees have been set on fire with as low as 100 watts. Be careful! A rule-of-thumb that I use is: For a resonant half-wave dipole, the voltage at the ends is *about* 20 times the feedpoint voltage, nothing to be sneezed at. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#7
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That depends upon whether it is a pole (tree) that is dying.
"John DeGood" wrote in message ... K5VSE wrote: I live in the forest, and use a couple of resonant dipoles hiding in the trees. I have no problems at all. Once, during our ice storm, one of them came down when a tree broke off and fell. Please allow me to apologize in advance, but I can't resist asking: "If a dipole falls in a forest and there's no one there to hear it, does it make a sound?" 73, John NU3E :-) |
#8
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I have 160m Inverted Vee in the trees, works fine. Just make sure that the ends
(last third) are in the clear. They have high voltage and prone to ignite fires when situation favorable. Use insulated wire. Yuri, K3BU.us |
#9
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"If a dipole falls in a forest and there's no one there to hear it,
does it make a sound?" =============================== Yes. All falling trees make a sound. But if there's nobody to hear it who cares? But this business about 100 watt transmitters causing forest fires is exaggerated. Even if there's a conjugal impedance match between a dead leaf and the transmitter there's little to worry about even when its not raining. And the density of foliage is hardly likely to allow flames, should they occur, to leap from one leaf to another. The climate and type of tree involved is, of course, of some consequence. Deciduous trees and those found in South American and Indianesian jungles can be disregarded from this discussion, If you should live in Australia, the home of Eucaliptus trees, during the dry season, and it's always dry, there is a one in 100 million chance of a tree catching fire by radio. Always supposing by some remote chance it hasn't first been struck by lightning. Eucaliptus trees positively enjoy fire. They depend on it to propagate efficiently. This may be an unfortunate trait insofar as kangaroos and wallabies are concerned but alligators are quite happy with the way things have been arranged. The Aussies themselves take care not to build their houses too near to eucaliptus plantations. The Abbo's, with their 50,000 years of experience, radio or not, are quite happy and sensible enough to leave things as they are. The USA has wide variations in climate and tree population. Thoughtful citizens ought to concentrate their minds on hurricanes, twisters, atmospheric pollution and gun laws. 100-watt transmitters and G5RV's can look after themselves. ;o) --- Reg. |
#10
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![]() "Reg Edwards" wrote The USA has wide variations in climate and tree population. Thoughtful citizens ought to concentrate their minds on hurricanes, twisters, atmospheric pollution and gun laws. 100-watt transmitters and G5RV's can look after themselves. ;o) --- Reg. I assure you we are concentrating very carfefully, Reg! Last week we had about 20,000 gun laws on the books, counting all federal and state laws. This weekend we have one less federal gun law, and soon there may be less. When free people use their minds instead of letting foolish emotions be their guide, the concept of restricting firearms from law abiding citizens is one of the first things to go. Btw, so far my dipole hasn't set the pine trees on fire, or been torn down by a hurricane, despite three attempts by them so far this year ;-) 73, Jack |
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