Jim, the route you've outlined sounds fine, and if you follow a few
basics along the way your operating problems should be minimal, as well
as solvable, if any.
1. On the route, minimize the number of turns, and where needed make them
of the largest possible radius - strive for a minimum of 1 foot, and keep
them gradual and smooth(picture sweeps, not elbows).
2. Provide a 180 degree smooth twist in about every 1 to 2 foot of run -
from the antenna to the tuner. Outside, it will better "ride the wind,"
and inside, RF coupling to other conductors will be minimal.
3. Maintain the distances you've mentioned from other conductors, RFI
sources, reflectors, water pipes(metallic OR plastic), and growing
vegetation. Worst case - it should ride in the center of an imaginary 6
inch pipe. You can use tie-offs of string in the rafters, and, if you
have to go through a metallic wall, a short piece of 6"PVC pipe with
slits in a matching cap on each end for the LL works well. Wrap that part
of the twisted LL in a few turns of faceless fiberglas insulation, and
slide into the pipe. Make the big hole in the wall near the ground, away
from all other TX lines, and plan for a lightning arrestor just outside.
If you MUST pass or cross a pipe, weatherstrip, or the like, closer than
3-4 inches, support the LL in such a way that both conductors are
equidistant from the surface of whatever it is for 3-6 inches. This will
make the small field created be self cancelling.
4. ALWAYS match the system at minimum power, and watch the SWR as you
operate - even a windblown tree branch, lawn sprinkler, precip, etc., can
raise it to a dangerous level when you increase the power.. Clean the LL
now and then, w/any kind of stuff like "Pride," to minimize dirt buildup
that will stay wet in the rain or dew - it can de-tune the match to the
point of disaster.
Have fun
Press Jones, N8UG, The Wireman, Inc., Landrum, SC, 29356
Sales (800)727-WIRE(9473) or orders@thewireman.com
Tech help (864)895-4195 or n8ug@thewireman.com
http://www.thewireman.com and the WIRELINE bargain page
Our 22nd year!
On Mon, 26 Apr 1999 05:40:03 PDT "James Apple" <wb1dog@hotmail.com>
writes:
>
>
> I would like to replace the coax from my cloud burner loop with
>Ladder Line. I have looked through the Handbook and other antenna
>books and have found information on running ladder line past/over
>large metal surfaces (roofs etc). But I have not found any practical
>
>info on running it once you get inside the house ?
>
> I live in a raised ranch style house with the shack in a front
>room and the antenna's out back. I could bring the Ladder Line into
>the house about 6 feet off the ground and run it in between the
>floor joists
>then up through the wall to the shack. This run will be about 18'
>long and I was planning on using 2" plastic conduit to house the
>line. This route however will pass within about 24" of several
>fluorescent lights and some other house wiring. Will this be a
>problem ?
>
>Thanks in Advance
>
>Jim Apple - WB1DOG
>
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