Hello all. A few months ago I found an old Mosley CL-36-M six element
tribander atop a local tower. The owner said that I'm free to have the
beam if I take it down. It has been atop the tower for 20+ years and has
been thought several hurricanes, ice storms, and busts of high wind and
has been heavily exposed to rain.
It's not rusted as far as I can tell and it shows no obvious structural
damage, abnormality, or signs of wear but upon hooking an MFJ Antenna
Analizer to the feedline I observed some strange results. The SWR's were
as follows:
28.000 mhz 4.0 SWR
29.000 mhz >25 SWR
-lowest at 28.134, 3.5 SWR
21.000 mhz 4.1 SWR
21.450 mhz 9.0 SWR
-lowest at 21.135, 3.3 SWR
14.000 mhz 8.2 SWR
14.350 mhz 16.5 SWR
-lowest at 14.160, 3.8 SWR
What on earth could cause SWR readings like that? Could it be something
as simple as a component of the antenna not making contact where it
should or damaged traps or is it something more complex? The antenna
shows relative SWR dips in all of the bands, is that significant? What
are the odds of being able to fix this? All comments greatly
appreciated.
73, Nat, WZ3AR
<nat@ajheatwole.com>
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