PS: Hi, I failed to address Howard's last question ref. using grease to pack
the PL 259. Grease is not necessary if you heed that the most important aspect
of any outdoor connections is to be sure the connections are water proof (not
just moisture proof). This means that you must start at about 3" from the
connector and wrap over the cable and up over the whole connector assembly and
on to whatever the connector is plugged into.
Try to picture any hard to see void, or the threads of a PL259, or other
connector, going into the SO239 (the UHF female) of the antenna. Your goal is
to prevent any moisture from invading those threads or any void whatsoever.
There are excellent tapes for this undertaking. I use Amp Fusion tape only
because I have a lot of it on hand. But there are updated tapes… none of which
are sticky or tacky and their adhesion, Like Amp Fusion tape, is enabled by
stretching the tape prior to application then applying with tension on the tape
as you wrap it.
I have seen "Rescue Tape" and Coax Wrap (not to be confused with Coax Seal, a
very well known that is not actually a tape… Although I think Coax Seal works
fairly well, it is tough to get off after a period of time whereas the other
"tapes" are easily taken off if you use a sharp single edge safety razor blade
or sharp box cutter.)
So, bottom line: wrap tapes with a second layer over the first, and if they
clearly indicate they are UV proof, OK, if not, use a UV electrical tape as the
third layer. NEVER depend on std electrical tape (PVC or the old type friction
tape) to provide you with moisture or waterproofing.
I'd be curious what you folks are using for UV resistant electrical tape
lately? I'm sure that what I am using is outdated, and I don't have an ID on
it any longer.
Thus, a good wrap that's water proof should not need any grease and actually
you should be fine with Nickel body connectors vs. the aged old , best choice
when any doubt, Silver plate body, silver plate pin and teflon dielectric.
The only dielectric grease I recommend is GE dielectric grease. Do not use
conductive grease in any type of connectors, obviously.
> Good DX, 73, Steve K1PEK
> DAVIS RF Co, Div. of Orion Wire Co., Inc.
> DavisRF.com
> Affiliates: Davis/Orion Marine Cable
> Davis Rope and Cable Assembly (DavisRopeAndCable.com)
>
>
> 4. Re: Ultraflex coax questions (Bury-Flex Tm and crimp dies)
> DAVIS RF Response (Stephen Davis)
>
> Message: 4
> Date: Mon, 15 Dec 2014 18:36:09 -0500
> From: Stephen Davis <sdavis@davisrf.com>
> To: towertalk@contesting.com
> Cc: W6HDG@arrl.net
> Subject: Re: [TowerTalk] Ultraflex coax questions (Bury-Flex Tm and
> crimp dies) DAVIS RF Response
> Message-ID: <D41677DF-32B5-480C-AF34-2C43ED8D8C87@davisrf.com>
> Content-Type: text/plain; charset=windows-1252
>
> Hi Howard,
>
> Yes, Bury-Flex ? will well outlast LMR-400 UF. Times uses a TPR
> (thermoplastic elastomer) outer jacket to enhance flexibility. TPR is not
> great for lasting in UV more than 6-8 years. When I designed Bury-Flex ?, I
> used a med. density PE outer jacket which is highly resistant to UV, certain
> chem's, and totally waterproof at outdoor temps/ambient pressure to fairly
> high pressure. I also used 19 strand to enhance flexibility vs. 400 UF which
> is a 7 strand (less flex).
> Bury-Flex ? is a very popular cable for not only hams but also NASA uses it
> (ground station), Lockheed Martin, FAA, etc. The "smoothness" of the outer
> jacket reduces friction thus excellent for coil around crank up towers. The
> cable can be buried without conduit, run thru water, ponds, salt water (have
> at least one ham who feeds his 4 el vert phased array which is in salt water
> inlet.
>
> RF Industries which you mention: an excellent quality source of commercial
> grade connectors. We are an authorized distributor for them for over 20
> years, never a problem. The RFU-507SI (silver body, silver pin, teflon
> dielectric) are excellent , thus you have chosen the right one for this
> cable.
>
> The die that you use is same as for LMR-400, 9913, Bury-Flex: .128 and
> .429, which you have.
> If you need strip dimensions, RFI has that in their catalog, and on their
> web site but if any problem, I can send those to you with the "Stripping Key"
> diagram (search that name on their web site and I think (?) you can find it
> there too.
>
> Good DX, 73, Steve K1PEK
> DAVIS RF Co, Div. of Orion Wire Co., Inc.
> DavisRF.com
> Affiliates: Davis/Orion Marine Cable
> Davis Rope and Cable Assembly (DavisRopeAndCable.com)
>
> Message: 2
> Date: Mon, 15 Dec 2014 08:41:26 -0800
> From: Howard W6HDG <W6HDG@arrl.net>
> To: towertalk@contesting.com
> Subject: [TowerTalk] Ultraflex coax questions
> Message-ID:
> <20141215164127.MRSZ11247.fed1rmfepo203.cox.net@fed1rmimpo110>
> Content-Type: text/plain; charset="us-ascii"; format=flowed
>
> Hi all. I am about to order about 110 feet of coax for a new
> MA770MDP tower/ Steppir DB18 install. I'm thinking of using either
> genuine LMR400 Ultraflex or Davis Bury Flex coax.
>
> Davis BuryFlex is cheaper and I understand it has a tougher and more
> slippery jacket for crank up/down use? Opinions?
>
> I am going to try crimp-on RFU-507SI RF Industries PL-259's for the first
> time. For the center conductor crimp, I have alternatively
> heard of .118 and .128 crimpers being used. I have the dies for
> both .118 and .128 as well as the .429 braid crimp. Any opinions? Do you
> use any dielectric compound such as STUF inside the PL259 to inhibit
> corrosion?
>
> Tnx, Howard W6HDG
>
>
>
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