In a message dated 96-03-16 12:13:36 EST, you write:
>Hi, Steve. I've been doing the tape-ScotchKote-tape thing, but not the
>vapor wrap. What is this stuff and where should I look for it?
>
Hiya, Steve --
Good question, actually. I didn't mean to be so hard on CoaxSeal
(personally I don't care for it) but it will work in this kind of scenario.
The problem is most guys apply it DIRECTLY to the connector which makes the
connector unusable again. YUCK! Install the CoaxSeal OVER the first layer
of tape and it will work.
As far as the butyl rubber vapor wrap, try the yellow pages for a local
Andrew, DB Products or Antennas Specialists dealer; they should have it. The
manufacturers always pack some in with some of there products but you may be
able to get small quantities. Otherwise, check back with me a a few weeks --
I may have some for you.
73 and good luck, Steve K7LXC
>From John Brosnahan <broz@csn.net> Sat Mar 16 18:51:38 1996
From: John Brosnahan <broz@csn.net> (John Brosnahan)
Subject: Andrews Hardline connector question per K7LXC
Message-ID: <199603161851.LAA22135@lynx.csn.net>
Just a couple of additional thoughts on Steve's comments
about sealing connectors.
>1) Apply two wraps of electrical tape over the joint (I recommend Scotch 33
>or 88 myself).
Scotch 88 is really the all weather tape to use. Scotch 33 tends to get
brittle in cold weather and has more of a tendency to lose its grip with time,
weather, and just a little stretching. 88 is a little more expensive but
I would never use anyhting else outdoors.
>2) Apply a layer of butyl rubber vapor wrap over the joint making sure that
>there are no air cavities or openings in the wrap. BTW, this is BETTER than
>CoaxSeal.
Butyl rubber tape is available from most good electrical supply houses.
>4) Somewhat optional -- coat joint with Scotch-Kote sealer. I've seen some
>guys use spray urethane over the joint. It's another layer of protection
>whichever you use.
I think Scotch-Kote is a waste of time if the connection is exposed
to the sunlight. Within a year it has degraded from the ultra-violet
and has pretty much flaked off (at least in Colorado). It is fine for
direct burial, for which it is intended. I actually like Plasti-Dip, which
is available from most hardware stores and is used to dip tool handles
for insulating them. Use the black color for better UV resistence. It
can be painted on (pretty thick goop) or there is a spray version as
well.
For things like splitting out the pigtail lead of coax to hook to
a sloper or a dipole (after the balun) I do a couple of layers of Scotch
88 with alternating layers of the Plasti-Dip by just dunking the end
into a gallon can of the stuff. Put some masking tape over the terminal
lugs to eliminate having to clean them off.
Another technique I use for weather proofing the pigtail ends of coax
is to put some heat shrink over the entire length of exposed dielectric
up to the point where the braid splits off. Then, taking a length of larger
diameter heat shrink, I cut a little slot in the middle and place that over the
jacket and heat-shrink-covered dielectric in such a way that the braid
sticks out the little slot. I dip this whole thing into a thinned down
version of Plasti-Dip (you don't need their thinner--it is just expensive
paint thinner/mineral spirits). This thinned down material soaks
into the braid--filling up the gaps to reduce the possibility of
wicking moisture into the region between the braid and center
conductor.
Yep, I know it is a lot of work, but how many times do you want
to replace your coax because it got water inside and the losses
sky-rocketed.
73 John W0UN
John Brosnahan
La Salle Research Corp 24115 WCR 40 La Salle, CO 80645 USA
voice 970-284-6602 fax 970-284-0979 email broz@csn.net
>From Dan Robbins <kl7y@alaska.net> Sat Mar 16 19:23:38 1996
From: Dan Robbins <kl7y@alaska.net> (Dan Robbins)
Subject: WX-proofing
Message-ID: <9603161923.AB25173@alaska.net>
Butyl rubber tape is definitely the way to seal coax connections, especially
for CONTEST stations. You can put Scotch 70 on at any temperature, even 50
below. The stuff is UV degradeable, so it has to be covered with a couple
of layers of Scotch 88. It removes so easily - just slit the tape with a
knife and it peels back better than a ripe orange. It sticks to itself, not
the coax or the connector. Just like magic! The price was $19 per roll the
last time I priced it, so even magic has its price.
Dan KL7Y
>From Walt Kornienko <k2wk@crystal.palace.net> Sat Mar 16 21:24:40 1996
From: Walt Kornienko <k2wk@crystal.palace.net> (Walt Kornienko)
Subject: Andrews Hardline connector question
Message-ID: <199603162124.QAA16642@crystal.palace.net>
Re: good hardline connections Steve, K7LXC writes:
>
> 1) Apply two wraps of electrical tape over the joint (I recommend Scotch 33
> or 88 myself).
> 2) Apply a layer of butyl rubber vapor wrap over the joint making sure that
> there are no air cavities or openings in the wrap. BTW, this is BETTER than
> CoaxSeal.
What is this stuff, where is available and does it have a Scoth
part #?
I know Scotch makes a "self-annealing" tape but I can't seem to
find it anywhere in Northern new Jersey. Does anyone know the
Scotch part # for this tape, too?
> 3) Apply 2 wraps of electrical tape over the joint with the final wrap going
> UP to minimize water migration.
> 4) Somewhat optional -- coat joint with Scotch-Kote sealer. I've seen some
> guys use spray urethane over the joint. It's another layer of protection
> whichever you use.
>
Let's see if I have this right: You apply a total of 5 layers of
tape over the joint?
> This technique should be used with ANY outdoor coax joint. It'll last
> for years and when you take your razor knife and open the joint up, it'll be
> just like new inside.
Sage advice!
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* 73 de Walt Kornienko - K2WK (FRC) *
* k2wk@crystal.palace.net or K2WK@N2ERH.NJ.NOAM *
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