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Antenna recommendation needed
Ralph Mowery wrote:
"Bruno" wrote in message ... Hi all, I've had a planning application for a tower turned down which is a real pain. My options are now very limited. I'm in a bungalow with a roof apex height of 18 feet and I'm not allowed to put up anything much above this roof line it transpires, so inverted vees that need to be mounted high up at the feed point like G5RVs are not possible for me. My garden boundaries limit the length of any wire antenna I might wish to put up to about 120 feet overall. On the plus side, though, the QTH is several hundred feet ASL close to the top of the hill and am not overshadowed by any trees or buildings to speak of. What's my best choice for an HF antenna under these circs? (I mostly do CW on 20m & 40m, but would like a bit more band choice ideally if poss). Many thanks. You will not need a tower, just a pole to support a HEX Beam. It is basically a 2 element beam and they seem to work very well at heigths of around 20 feet. Most are from 20 meters up, so a wire dipole for 80 and 40 metes will probably be needed also. A trapped dipole will shorten it up slightly . 20 feet is just a bit less than a half wave at 20 M, so a HEX beam (or any horizontal antenna) will work fairly well at that height. For the bands above 20 M you are above a half wave length. A dipole for 40 or 80 meters at 20 feet will radiate straight up, which is OK if you are only interested in local communications. FYI miltary NVIS communications useually takes place on 2-4 MHz at night and 5-7 MHz during the day. -- Jim Pennino |
#2
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Antenna recommendation needed
wrote in message ... A dipole for 40 or 80 meters at 20 feet will radiate straight up, which is OK if you are only interested in local communications. FYI miltary NVIS communications useually takes place on 2-4 MHz at night and 5-7 MHz during the day. At one house I lived in all I could put up was an 80 meter dipole at just under 20 feet. The center was supported by two pieces of electrical pvc type pipe. It had a good signal out to about 300 or so miles, and less at other distances. Worked fine at the time to talk to some locals to 300 miles in the eairly mornings. When limiated as to what you can do, just stick up something to start with and later work on getting something beter. |
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