A few years ago I put up a temporary 60 foot vertical over
my 230 foot diameter ground screen. It was top loaded with 2
"umbrella" wires sloping down. The bandwidth was MUCH
narrower than your 65 foot vertical. IIRC, the 3:1 VSWR
bandwidth was less than 50 kHz. The feedpoint impedance
was about as predicted by EZNEC over a perfect ground.
IE, very low. It got out really well in contests
(anecdotal "data"). If you are seeing a bandwidth broad
as a barn door, it can probably only be explained by
substantial ground losses. I understand you can't get
a ground like I have, do the best you can and get on
the air.
Rick N6RK
On 11/20/2014 8:11 AM, Joe Galicic wrote:
I moved my 160 inverted L to a tall tree in my backyard to get more vertical
height. The vertical leg is now about 65 feet and the rest (65feet) is
horizontal. I fed this one with about 125 feet of 75 ohm coax just because I
had lots of it laying around. No tuners, baluns, ununs or chokes in the feed
line. The ground is connected to the existing ground system for the old L. I
get a 1.1 SWR reading from 1.8 to 1.9 before it moves up to 1.3 and slightly
higher to 2.0. The antenna seems to be working OK (relative to the old L). This
seems awfully broad banded? Any feedback would be great. Thanks -Joe N3HEE
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