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Old February 8th 07, 10:58 AM posted to rec.radio.cb
Frank Gilliland Frank Gilliland is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 432
Default SWR and buildings

On Thu, 8 Feb 2007 10:10:33 -0000, "Dave P"
wrote in :

From my understanding when you are checking SWR you should be 50ft away from
buildings etc. I'm just wondering how big an effect being close to a
building can have on SWR? If my SWR if around 2 (that'll do me) and I find
myself in a town near a building or in a jam with a big 18 wheeler alongside
could I find that my SWR could go from 2 to a damaging level due to the
closeness?



Never heard of it happening or seen it happen myself. Objects like
buildings and the sheet metal on trucks will absorb far more RF than
they will reflect. Any -significant- reflection, enough to potentially
hurt your radio, requires a thin, straight conductor, parallel to your
antenna, with a specific length, and at a specific distance. Matter of
fact, some people who build their own antennas and -want- that kind of
reflection often find out that it's not easy -- certainly not as easy
as mounting a vertical next to a building or truck.

If you check SWR and it's over 3:1, most likely there's something
wrong other than just being close to a building or truck.