[TowerTalk] Dielectric grease Re: Ultraflex coax questions (Bury-Flex Tm and crimp dies) DAVIS RF Response (Stephen Davis)

[Stephen Davis]

 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  I'm sure that what I am using is outdated, and I don't have an ID on it any longer.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 at davisrf.com>
> To: towertalk at contesting.com
> Cc: W6HDG at arrl.net
> Subject: Re: [TowerTalk] Ultraflex coax questions (Bury-Flex Tm and
> 	crimp	dies) DAVIS RF Response
> Message-ID: <D41677DF-32B5-480C-AF34-2C43ED8D8C87 at 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 at arrl.net>
> To: towertalk at contesting.com
> Subject: [TowerTalk] Ultraflex coax questions
> Message-ID:
> 	<20141215164127.MRSZ11247.fed1rmfepo203.cox.net at 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

> 
> 
>