A few weeks ago, on returning home from a 2-week drive to
Spokane, WA, and back, I found some equipment in the
house was apparently affected by a lightning strike either
directly on the house or nearby. Among the immediately
noticed affected hardware were the remote coax switch
control box (the switch turned out to be fine; the controller
had its power transformer expanded in size by about 30
percent--replaced it and the fuse and it works fine), and
my Omni VI.
I put my MFJ-259 on the antennas and they seemed okay.
The Omni VI came back from Ten-Tec yesterday. On
putting it on the air, it seemed back to it's super self.
However.....
The upper A3 at 70' on the tower seems to hear okay
(sigs are down by about 2 s-units when compared to
the lower A3 at 40'). But, on rotating it, there is no
evidence of directivity. I was hearing ZP5KO nicely on
20m last night. I rotated the beam from SE to NW then
to W and S and there should have been some change
in his signal strength; there wasn't. 10, 15, and 20m
SWR is up to about 1.8 to 1 on the three bands. It's
kind of like I am listening to/operating into a dummy
load up there.
I hope to be able to go up there, weather permitting either
tomorrow or Monday and check out the antenna.
Preliminary to that, can anyone offer anything I might
consider as the likely problem? Blown trap(s)?
Blown/affected balun (I used the 9 turn coax cable coil
type--in fact, I built a new one last night in anticipation
that it might be the problem; if not, I'll use it elsewhere)?
Has anyone experienced anything similar with their
antennas? What was the solution?
My plan is to simply check out the cable run back to a
dummy load on the ground with the 259, then check out
the balun and antenna with the 259. If the cable run
checks okay, then the problem will be with the antenna.
Since I am only getting higher than normal SWR, but still
nominal (i.e., below 2:1), and directivity seems screwed up,
my thoughts are that the reflector or director element(s)
may be affected.
I'd appreciate any thoughts on this.
Thanks in advance.
73,
Dale Martin, KG5U
kg5u@hal-pc.org
http://www.hal-pc.org/~kg5u
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