Just to make sure we are all speaking of the same cable, RG-400/u is a
Teflon 0.195" diam (RG-58 class) cable with two shields and a stranded
center while LMR400 is a 0.405" diam (RG-8 class) cable with a single
copper clad aluminium center and double shielded with a 100% foil shield
and an 88% braid.--Mike, WV2ZOW
On Tue, Jun 7, 2016 at 7:32 PM, Chet S <chetsubaccount@snet.net> wrote:
> Mark,
>
> In a pinch, I have cut off 1 or 2 strands of the center conductor to get
> the
> LMR-400 into the center pin.
>
> Better, attached below is some info about this from a recent thread on the
> Yankee Clipper Contest Club forum that you may find of use.
>
> 73,
> Chet N8RA
> _______________________________________
>
>
> A standard clamp N connector will fit LMR400 but you have to put the center
> pin in a lathe and bore it out slightly. HOWEVER - LMR style cables don't
> have a very thick braid shield like RG8/RG213 so the possibility of a
> spinning connector is very possible. These cable rely on the inner foil
> shield along with the braid to get the job done and thus a crimp connector
> is the way to go. ALWAYS solder the center pin on these cables. I've run
> 1kW
> at 1296 through LMR with crimp connectors without any issues.
>
> Contact Joel at the RF Connection for a stripping tool and a crimper, he
> sells one that does RG58/RG8X and RG8/LMR all in one and it's pretty
> reasonable. You can also get heat shrink tubing from him that has heat
> activated sealant on the inside that will keep water out of the crimp area.
>
>
> Terry Price
> W8ZN - ex K8ISK/WD8ISK
> 1.8 MHZ - 47 GHz - FM18dv
> Member of the K8GP Contest Group
> FM19bb
>
> I only use the Genuine PL259: Amphenol 83-1SP. $4.55 from DX Engineering,
> about the same at Mouser. They work fine on LMR400 without having to put
> them on a lathe. Silver-plated body which takes solder well, nickel shell.
>
> Clamp-type N connectors for LMR400 and 9913 are available and different
> from
> the standard ones. I bought some at Deerfield last weekend. Amphenol part
> number is 172113H243, about $10 at Mouser. DXE does not seem to carry them
> yet. Let me work on that...
>
> I do not use crimp-type connectors. I guess they are OK indoors, but I find
> soldering PL259s to be relaxing.
>
> Never never never buy cheap connectors. You'll be sorry one day.
>
> 73,
>
> Doug K1DG
>
>
> Amen, amen, and AMEN!
>
> More than ten years ago, after having experiencing MANY failures of cheap
> imitations, I reverted to genuine Amphenol connectors. I have yet to see a
> genuine Amphenol PL-259 fail. The additional cost of genuine Amphenol
> connectors is repaid MANY times over by the avoidance of station downtime
> and time spent troubleshooting and repairing bad connections.
>
> Three more things to know about PL-259s:
>
> 1. Solder them by means of an iron having a massive copper tip, from which
> sufficient heat can flow to bring the connector and the shield-braid of the
> coax up to solder-flowing temperature quickly, without the tip cooling
> down.
> The small tips of typical soldering-station irons do not store sufficient
> heat. The tips of typical soldering guns do not either. It is the heat
> capacity of the tip, not the power of the resistive heater, that is
> critical. Fast heating of the connector and braid is critical because the
> soldering must be completed before the outer plastic sheath and/or the
> inside plastic dielectric of the coax soften and melt.
>
> 2. After screwing a PL-259 plug onto an SO-239 or equivalent socket by
> hand,
> use gas pliers to tighten the connection further. Finger-tight is not
> tight
> enough because, in time, with thermal and perhaps also mechanical cycling,
> the connection will loosen.
>
> 3. An outdoor connection should be over-wrapped with Scotch 33+ or 88
> electrical tape, and then over-wrapped again, with tape or sealing putty
> such as Coax-Seal or (much less expensive and preferable IMO) the stuff
> used
> by cell-site installers. The first wrap of tape will enable you later to
> remove the putty without it sticking to and gumming up the connector(s).
> Some sealing putties must be over-wrapped with tape to keep solar UV from
> destroying them. A sealed PL-259 connection will remain bright and shiny
> for decades.
>
>
> -Chuck W1HIS
>
> I have tended to overdo weatherproofing of outdoor connections with
> multiple
> wraps of Super 88 and an outer wrap of Cold Seal tape (maker unknown, Radio
> Works sells it) that is non-adhesive and provides a weather-tight shrink
> wrap when stretched while wrapping. I bought a couple of rolls of a
> similar
> non-adhesive tape at Visalia last month, "CoaxWrap", available from HRO and
> others. I did an antenna repair job last week and used CoaxWrap as the
> INITIAL layer this time, then two wraps of Super 88 and a bit of Coax Seal
> around the interface between coax connector (all Amphenol) and feedpoint
> balun. The nice feature of non-adhesive tape as the first layer, of
> course,
> is that it is much easier to remove from the coax connector (along with the
> outer 88 layers) if necessary for future repair.
>
> www.coaxwrap.com
>
> George W1EBI
>
> This sounds like silicone self-fusing tape. One brand name is Rescue Tape.
> Here is the 3M version:
>
> http://solutions.3m.com/wps/portal/3M/en_US/NA_Communication_Technologies/Ho
>
> me/Products/~/Scotch-Self-Fusing-Silicone-Rubber-Electrical-Tape-70-1-in-x-3
> 0-ft?N=8694169+4294907179&rt=rud
>
> There is a guy at Dayton who sells it. He demos it with a 1/2" x 3"
> piece. He says "stick out your finger", and wraps it around it tightly.
> When it immediately cuts the circulation off in their finger, they are
> usually convinced.
>
> What I like about it is that it comes off cleanly. I prefer it to other
> tapes. If I am really worried about a connection, I cover the silicone
> tape
> with vinyl to provide some UV protection.
>
> Tom - N1MM
>
> Last year I took apart a number of outside connectorions after 30 years in
> service and they were all perfect, no signs of any
> moisture! I had first wrapped the connection with 3M self-fusing tape to
> keep the connector clean, followed by Scotch 88, then
> Coax-Seal and a final layer of Scotch 88 for UV protection. I was very
> impressed! You ABSOLUTELY need to protect the
> self-fusing tape from UV, otherwise it'll get brittle in no time.
>
> --- Rich K1CC
>
>
> 30 year old self-fusing tape is different from silicone self-fusing tape.
> The silicone (according to the 3M description) is UV resistant.
> The linerless rubber splicing tape (what you probably used) says it is UV
> resistant as well. Of course, that doesn't mean either one will last
> 30 years in Phoenix.
>
>
> http://multimedia.3m.com/mws/media/143045O/3mtm-scotchtm-130c-linerless-rubb
> er-splicing-tape.pdf
>
> Tom - N1MM
>
> -----Original Message-----
> From: VHFcontesting [mailto:vhfcontesting-bounces@contesting.com] On
> Behalf
> Of Mark Spencer
> Sent: Tuesday, June 07, 2016 3:01 PM
> To: VHF Contesting <vhfcontesting@contesting.com>
> Subject: [VHFcontesting] PL 259 crimp connectors for RG 400
>
> Hi does anyone have any recent experience buying generic PL 259 style crimp
> connectors for RG 400 style cable and if so could they share their vendor
> contract info with me ?
>
> My last few batches of generic connectors have had centre pins which are to
> small for the RG 400 centre conductor. I would prefer a generic connector
> for this application vs a pricey name brand one. I'm making up some patch
> cords for portable work and they may only last a for a few outings.
>
> I'm using generic RG400 cable which may also be part of the issue. The
> cable and connectors were sourced from the same vendor.
>
> Plan B is to simply drill out the centre pins of the connectors that I
> have.
> I already have the RG 400 sized ferrules.
>
> Thanks in advance
> Mark S
> VE7AFZ
>
>
> Sent from my iPhone
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