Hot Buttered Toast...

[KM9P at aol.com]

I just came in from the garage where I was working on some phasing lines and
was reminded of what can happen when one doesn't properly seal coax
joints....  Loss!

Lew Gordon (K4VX) told me about this product from 3M many years ago.  It's
called Skotchcoat.  Its a slimmy, black, brush-on mess that is applied to 3M
(or other) types of electrical tape.  Lew always told me that he would use 3
coats of tape with each coat getting pasted with the Skotchcoat.  Since I've
had my station up for 5 years now and am in the process of taking it down, I
can tell you that so far I have not found a coax fitting or joint that looked
any less than new if it was originally sealed following Lew's guidelines.  

This stuff is better than hot buttered toast!

73

Bill Fisher, KM9P

ps  Sorry for breaking up the all too interesting field day discussion.


>From Dave Hawes <34703 at vlf03v31.ueci.com>  Wed Jul  6 19:50:05 1994
From: Dave Hawes <34703 at vlf03v31.ueci.com> (Dave Hawes)
Date: 6 Jul 94 14:50:05 EDT
Subject: Hot Buttered Toast...
Message-ID: <12236C334FD at vlf03v31.ueci.com>

> Lew Gordon (K4VX) told me about this product from 3M many years ago.  It's
> called Skotchcoat.  Its a slimmy, black, brush-on mess that is applied to 3M
> (or other) types of electrical tape.  Lew always told me that he would use 3
> coats of tape with each coat getting pasted with the Skotchcoat.  Since I've
> had my station up for 5 years now and am in the process of taking it down, I
> can tell you that so far I have not found a coax fitting or joint that looked
> any less than new if it was originally sealed following Lew's guidelines.
>
> This stuff is better than hot buttered toast!
>
> 73 Bill Fisher, KM9P

After suffering water incursion into the N fittings at the top of the
tower where the hardline connects into a jumper for the PacketCluster UHF
link antennas, I decided to take the advice of an electrician friend of
mine who used to make taped HV power cable splices for a living.  You
guessed it!  3 layers of Scotch 33+ tape, each covered with a generous
coating of Scotchkote.  Since that time (5 years, or so), the N fittings
have remained dry.  (It's amazing how a little water in an N fitting at
UHF will bring a packet link to its knees.)

This weekend the feedlines to the UHF antennae are being replaced with
newer larger diameter ones, and the same 33+/Scotchkote procedure is
planned for the new fittings.  It works!

73 - Dave, N3RD



+---------------------------------------------------------------------+
| Dave Hawes                        Internet: 34703 at vlf03v31.ueci.com |
| Raytheon Engineers & Constructors    Voice: 215-422-3754            |
| Philadelphia, PA                       Fax: 215-422-4005            |
+---------------------------------------------------------------------+

>From K9VV - Fred Kleber <0006636049 at mcimail.com>  Wed Jul  6 21:24:00 1994
From: K9VV - Fred Kleber <0006636049 at mcimail.com> (K9VV - Fred Kleber)
Date: Wed, 6 Jul 94 15:24 EST
Subject: Whoops-Wrong Reflector!
Message-ID: <84940706202448/0006636049PK1EM at mcimail.com>

Cuuuzzzzze - thought the 3V8RR post went to the DX reflector.  Now about
how my shoes were put on that morning...
 
Fred Fubar, k9vv at mcimail.com

>From Steve Kelly <srkelly at agora.rdrop.com>  Thu Jul  7 00:00:42 1994
From: Steve Kelly <srkelly at agora.rdrop.com> (Steve Kelly)
Date: Wed, 6 Jul 1994 16:00:42 -0700 (PDT)
Subject: Hot Buttered Toast...
Message-ID: <Pine.3.87.9407061642.B12078-0100000 at agora.rdrop.com>

One thing I have noticed after years of Scotchkote use is that it does not
hold up well under direct sunlight exposure (usually only lasts a couple
of years).  The stuff is primarlly designed for direct burrial
applications where sun exposure is not a problem. 

My simple solution is to wrap the fitting to be waterproofed with a 
couple layers of scotch 33+ tape, apply the Scotchkote and let it dry for 
about 2 to 5 minutes, then over wrap the not quite dry Scotchkote with a 
last layer or two of 33+ tape.

I have never had a connection sealed in this manner leak!

Just food for thought.

KC7EM
Steve Kelly
srkelly at agora.rdrop.com



>From James White <0006492564 at mcimail.com>  Thu Jul  7 00:30:00 1994
From: James White <0006492564 at mcimail.com> (James White)
Date: Wed, 6 Jul 94 18:30 EST
Subject: CABLE QUERY Pro vs Con @ KC2X
Message-ID: <53940706233035/0006492564PK3EM at mcimail.com>


The following comments recently aired on the contest reflector:




" The question of whether to physically separate the control cable from
the hardline and coax brought mixed response; I have decided to run
them separately - it can't hurt, and might help, especially if I
ever get suckered into going multi-op."  (Steve, KC2X  Narcoosee, Florida)


I would like to go on record as never having suggested that Steve consider
go multi-op..........................................................yet


K1ZX


>From Lyndon Nerenberg <lyndon at unbc.edu>  Thu Jul  7 01:15:05 1994
From: Lyndon Nerenberg <lyndon at unbc.edu> (Lyndon Nerenberg)
Date: Wed, 6 Jul 1994 17:15:05 -0700 (PDT)
Subject: Hot Buttered Toast...
Message-ID: <Pine.3.87.9407061705.D1684-0100000 at unbc.edu>

On Wed, 6 Jul 1994, Steve Kelly wrote:
 
> My simple solution is to wrap the fitting to be waterproofed with a 
> couple layers of scotch 33+ tape, apply the Scotchkote and let it dry for 
> about 2 to 5 minutes, then over wrap the not quite dry Scotchkote with a 
> last layer or two of 33+ tape.

Well, my favorite for sealing up exposed coax connections is to *tightly* 
wrap with regular electrical tape, then heat shrink the whole mess.

When applying the tape make sure to add plenty of tension (the tape 
should visibly "narrow" due to the pull, but not to the point of 
breakage). This will cause the tape so "pull up" into the various gaps 
(such as the base of the connecter where the coax enters) and seal it. 
I usually do four passes of electrical tape, then apply the heat shrink.
The heat shrink keeps the UV away and provides a *very* rugged weather seal.

Last week I had to pull apart one of the 9913<->213 joints on our 
satellite antenna on the roof. After a year the connectors look just like 
they did the I broke the seal on the plastic package. (It's only been a 
year, but that year consisted of three months of almost steady rain and a 
typical Canadian winter.)

--lyndon


>From rking at sescva.esc.edu (RICHARD KING - K5NA)  Thu Jul  7 02:10:01 1994
From: rking at sescva.esc.edu (RICHARD KING - K5NA) (RICHARD KING - K5NA)
Date: Wed, 6 Jul 1994 21:10:01 -0400
Subject: Phonetics
Message-ID: <94070621100105 at sescva.esc.edu>

Since everyone else is doing it.

How about:

    Potassium Five Sodium

73, Richard - K5NA