I think we are talking about to different but relate issues. Anything that
can be direct buried should be. The PVC pipe is a more suitable solution if
cables aren't rated for direct burial or change of the installation is
anticipated (don't we all?). I have done both. The direct buried cable
have stood the test of time without failure, the PVC has made several
changes to antennas and control systems much easier when the plants, a
fence, trees grow up in the back yard. The XYL preferred the cost of the
PVC to frequent tearing up of the backyard.
Some time honored experience I have learned, you don't tie the cables
together in a bundle with ANYTHING. Tiewraps snag and tape bunches up and
adds an incredible amount of friction. Make sure the pull line is big
enough and when pulling in cables, lay them out in a straight line before
pulling and have someone wipe off the cable completely as it goes in, no
dirt. I have used the slippery stuff on the longer runs, but generally
found making the cable straight and assist by pushing the cable in one end
as you pull from the other is better. Using a reel supported so it can turn
as you pull sounds good but puts undesirable tension on the cable, and the
cable will have a curved set already formed in. This increases the friction
of the pull.
On the latest 650 foot run I put in, it was a 3" PVC and rather than "pull"
the cables in, I laid out the cables along side of the trench. I cut a
1/16" bevel around the inside edge of the flared end of the PVC pipe. This
helped the cables feed into the section. I then started by slipping the
first 20 foot section of PVC over one end, flared end first. I had a helper
cleaning the cables ahead of me. I tied the flared end of the PVC with a
rope that allowed me to suspend it a few inches off the ground and I could
pull in along until I reached the other end. Pulling the PVC so close to
the ground allowed the cable to easily slip though as I walked along. I
repeated this until all sections were lined up. We then glued the sections
together. Be careful not to get any of the glue get on the inside. It will
make any possible pulling out of the cable impossible. When finished gluing,
put one end of the cabled PVC in the trench and with the same rope make a
loose loop around the PVC and walk it into the trench. The whole 650 foot
job took two people one very long day. I hope this helps someone who has a
big job a little easier.
73's Mel, K6KBE
Original Message-----
From: Barry [mailto:w2up@mindspring.com]
Sent: Wednesday, October 03, 2001 7:38 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Feedline Pipe or tubing
Why pull hardline through a pipe? Sounds like more trouble than
it's worth. Just directly bury it. That's what the cable company does.
I have a 100 ft run of 4 inch PVC buried and pulled all my coax and
control lines through it. It was no easy task, especially when I
added a few more cables at a later date - my pull rope tangled
within the existing cable runs, etc. I wound up pulling everything
out to get everything back in.
When I added 2 hardline runs, I didn't even consider pulling them
through the conduit. I rented a ditchwitch for half a day (their
minimum), and in less than an hour dug a 4 inch wide by 2.5 ft
deep by 100 ft long trench parallel to my conduit run. Laid the
hardlines in, pushed the dirt back in. Easy!
73,
Barry W2UP
On 3 Oct 01, teamw wrote:
>
> I suggest that you NOT use the corrugated pipe. It could cause more
> friction and snagging on cables and connectors than you would want to cope
> with. If you ever get hold of some semi-rigid CATV hardline and try to
pull
> that in the pipe already occupied with other cables you would find out in
a
> hurry.
> I believe that most of the water (and you would be surprised how much can
> accumulate) will be from condensation. You cannot easily prevent this so
> the best thing to do is expect it and make sure that you use only high
> quality totally waterproof jacketed cables . In most cases this only
> requires making sure that there are no abrasions on the jacket that could
> allow water to penetrate to the shielding. You can help by having drain
> holes in the bottom of the pipe if you have dry terrain but if you are
like
> me the water table is virtually on the surface and I will have water
filled
> pipe on a near permanent basis.
> John AB4ET
>
>
> List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> Trylon Titan towers, coax, hardline and more. Also check out our self
> supporting towers up to 100 feet for under $1500!!
http://www.anwireless.com
>
> -----
> FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
>
--
Barry Kutner, W2UP Internet: w2up@mindspring.com
Newtown, PA Frankford Radio Club
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!!
http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
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