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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