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Old April 10th 04, 04:43 AM
zeno
 
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I was contemplating putting up a full wave 160m sky wire horizontal
loop. It will be kind of a square (more trapazoid actually). I was
hoping to use it multi-band. I am hoping to get the corners up on
metal masts up at least 50 feet.

1. Is it worth the extra trouble to get ladder line and feed into
the shack (house) (as opposed to coax)? I will have pulleys so I
could try one and then the other.

2. What length should I cut it for? I am new, don't particular know
what frequency I might be on. I had heard that the 160m loop
(approx. 540' or so) could be good as a multi-band. What exact
length should I aim for, or is it even critical? 1005/?

3. If I use ladder line, I would have to use a balun in the shack
to convert to coax a short run to go to my Kenwood Tuner (which has
160m), on other bands I would use a small Johnson Matchbox which
lacks 160m and eliminate this balun. I am envisioning some kind of
old- fashioned DPDT knife switch, I guess.

4. Actually, as a newbie, I have a nothing but more questions, like
how best to override the built in relay in the Johnson Matchbox
etc. I am gradually figuring this stuff out and hope to find some
locals also.

5. If the ladder line proves to be problematic (there are some
nearby tv cables, phone lines maybe 5-6' away at one closest point)
would a coax feed to this 160m loop still be multi-band? I am not
finding a consistent answer to this question anywhere online.

6. Glad to have found this board, since I am lately obsessed with
putting in an antenna farm on the real estate (very big rural back
yard).

7. I welcome any additions and/or corrections to my thinking so far
on this loop project. At this point, I am just scrounging together
the masts and pulleys etc. deciding whether to use rope or wire
guys...

-Bill


'Doc wrote:

'CYB',
A major lobe of a horizontal loop is 'straight up', but that
doesn't
mean that all the RF is going that way by any means, and a high
radiation
angle isn't always 'bad'. 'Tilting' a horizontal loop does
change the
direction of the radiation pattern, but because of all the
things that
affect the radiation pattern, where it actually 'goes' is very
hard (if
not impossible) to predict. Best advice? Try it and see what
happens.
I'm using a horizontal 80 meter loop on a city lot. I've had
no more
than the 'usual' problems working a WAS (several times), and all
the DX
I cared to 'mess' with. A loop has several good and bad
characteristics,
just like any other antenna, and what works well 'here' may not
work well
'there' (just like any other antenna). I just wish the thing
was at 60
feet instead of 20 (LOL)! A characteristic that I like is that
when fed
with ladder line through a tuner, (I know Cecil, but I've got
the tuner),
it works almost all bands, sort of a problem loading on 15
meters, but I
don't use 15 anyway.
Good luck...
'Doc