Eric, Most duplexers and multi-couplers that I have come across are from either Rx/Tx or Sinclair and all use the RG-214 with copper rather than silver plated conductors. You would think that if the difference was significant those guys would use the better of the two. Someone had suggested that small diameter LDF or FSJ be used as interconnecting cables for duplexers, multi-couplers and the like, but doesn't the "weakest link in the chain" principle apply? In other words, if even one piece of "crap cable" is used isn't it just as well as it all be "crap-cable"?
Your comments about the RG-142 are interesting. I use a short jumper as a rotation loop because it IS so flexible and tolerant to low temps. But this is for HF so maybe the dandruff issue isn't as important? Thanks for chiming in on this. Interesting stuff! lh On Sun, Mar 7, 2010 at 6:47 PM, Eric Lemmon <wb6...@verizon.net> wrote: > > > Larry, > > Real RG-214/U is genuine military specification cable, while "un-real" > RG-214 is ersatz, make-believe crap that fails to meet many or all of the > Mil-Spec requirements. Although such cable is supposed to have the work > "TYPE" following the part number, there are dishonest vendors who omit that > word and hope that the buyers are too focused on price to know that they're > buying junk. > > That said, I will admit that some reputable cable manufacturers do offer a > line of RG-214/U TYPE cable that is double-shielded with tinned or bare > copper braids and center conductor, rather than silver-plated braids and > silver-plated center conductor. Naturally, this cable costs much less than > the silver-plated variety. I would never shop for cable based solely on > price, but many people do. > > RG-142/U coaxial cable is good stuff, provided it will not be flexed after > installation. RG-142/U is identical to RG-400/U, except that the former has > a silver-plated solid steel center conductor, while the latter has a > silver-plated stranded copper center conductor. > > I have attached the Military Specification for RG-214/U cable as an > example. > It is also posted in the Files section of this Group. > > 73, Eric Lemmon WB6FLY > > > -----Original Message----- > From: Repeater-Builder@yahoogroups.com<Repeater-Builder%40yahoogroups.com> > [mailto:Repeater-Builder@yahoogroups.com<Repeater-Builder%40yahoogroups.com>] > On Behalf Of Larry Horlick > Sent: Sunday, March 07, 2010 3:25 PM > To: Repeater-Builder@yahoogroups.com <Repeater-Builder%40yahoogroups.com> > Subject: Re: [Repeater-Builder] Re: LMR Cable > > What is the difference between real and un-real RG214? And what is the > problem with RG-142? > > lh > > On Sun, Mar 7, 2010 at 6:24 PM, NORM KNAPP > <nkn...@twowayradio.net<nknapp%40twowayradio.net> > <mailto:nkn...@twowayradio.net <nknapp%40twowayradio.net>> > wrote: > > > > Those are usually the preferred types of cables. You should have no > problems with either of those. I prefer REAL RG214/U., but RG400/U, RG393 > or > RG223/U will work. Avoid RG-142 and RG-9/U. Superflex is also a good > choice. > Don't even think about any LMR type or > similar. > N5NPO Norm > > > ----- Original Message ----- > From: Repeater-Builder@yahoogroups.com<Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder%40yahoogroups.com<Repeater-Builder%2540yahoogroups.com> > > > <Repeater-Builder@yahoogroups.com <Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder%40yahoogroups.com<Repeater-Builder%2540yahoogroups.com>> > > > To: Repeater-Builder@yahoogroups.com <Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder%40yahoogroups.com<Repeater-Builder%2540yahoogroups.com> > > > <Repeater-Builder@yahoogroups.com <Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder%40yahoogroups.com<Repeater-Builder%2540yahoogroups.com>> > > > Sent: Sun Mar 07 16:54:30 2010 > Subject: Re: [Repeater-Builder] Re: LMR Cable > > > > > Any problems with RG-214 or RG223 for > duplexers/multi-couplers/combiners? > > lh > > > > On Sun, Mar 7, 2010 at 5:50 PM, Dan Saputo > <dan17...@yahoo.com<dan173mi%40yahoo.com> > <mailto:dan173mi%40yahoo.com <dan173mi%2540yahoo.com>> <mailto: > dan17...@yahoo.com <dan173mi%40yahoo.com> > <mailto:dan173mi%40yahoo.com <dan173mi%2540yahoo.com>> > > wrote: > > > > > well-documented and caused mainly by the use of foil shielding as in > the lmr series. gets worse as cable ages and internal braid-foil contact > degrades. Although not as big of a problem with lmr due to an insulating > layer over the actual foil. beware of belden 9913 and lmr look-alikes. > trouble when used duplex. > > Dan > k8plw > > > --- On Sun, 3/7/10, Chuck Kelsey > <wb2...@roadrunner.com<wb2edv%40roadrunner.com> > <mailto:wb2edv%40roadrunner.com <wb2edv%2540roadrunner.com>> <mailto: > wb2...@roadrunner.com <wb2edv%40roadrunner.com> > <mailto:wb2edv%40roadrunner.com <wb2edv%2540roadrunner.com>> > > wrote: > > > > From: Chuck Kelsey <wb2...@roadrunner.com <wb2edv%40roadrunner.com> > <mailto:wb2edv%40roadrunner.com <wb2edv%2540roadrunner.com>> <mailto: > wb2...@roadrunner.com <wb2edv%40roadrunner.com> > <mailto:wb2edv%40roadrunner.com <wb2edv%2540roadrunner.com>> > > > > Subject: Re: [Repeater-Builder] Re: LMR Cable > > To: Repeater-Builder@yahoogroups.com <Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder%40yahoogroups.com<Repeater-Builder%2540yahoogroups.com> > > > <mailto:Repeater-Builder@yahoogroups.com<Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder%40yahoogroups.com<Repeater-Builder%2540yahoogroups.com>> > > > > Date: Sunday, March 7, 2010, 4:56 PM > > > > Passive Intermod. In other words, it tends to be a source in which > intermod > can be generated easily. > > Chuck > WB2EDV > > ----- Original Message ----- > > From: "rffun" <radio...@her. forthnet. gr > <http://us.mc560.mail.yahoo.com/mc/compose?to=radiocom%40her.forthnet.gr > <http://us.mc560.mail.yahoo.com/mc/compose?to=radiocom%40her.forthnet.gr> > > > > > To: <Repeater-Builder@ yahoogroups. com > < > http://us.mc560.mail.yahoo.com/mc/compose?to=Repeater-Builder%40yahoogroups > .com > < > http://us.mc560.mail.yahoo.com/mc/compose?to=Repeater-Builder%40yahoogroups > .com> > > > Sent: Sunday, March 07, 2010 3:33 PM > Subject: [Repeater-Builder] Re: LMR Cable > > > <LMR and similar cables are not rated for low PIM> > > What exactly do you mean by PIM ? > > rffun > > > > > --- In Repeater-Builder@ yahoogroups. com > < > http://us.mc560.mail.yahoo.com/mc/compose?to=Repeater-Builder%40yahoogroups > .com > < > http://us.mc560.mail.yahoo.com/mc/compose?to=Repeater-Builder%40yahoogroups > .com> > , Larry Horlick <llhorl...@. ..> > > > wrote: > >> > >> Indeed. I'll read the archives. Thanks. > >> > >> 73 > >> > >> On Sun, Feb 28, 2010 at 8:59 PM, Chuck Kelsey <wb2...@...> wrote: > > >> > >> > > >> > > >> > The subject comes up on this list about every other week. I can > only > >> > assume > >> > you are new. > >> > > >> > LMR and similar cables are not rated for low PIM, a fact > verified by > >> > the > >> > manufacturer. > >> > > >> > Chuck > >> > WB2EDV > >> > > >> > > >> > > >> > ----- Original Message ----- > >> > *From:* Larry Horlick <llhorl...@. ..> > > >> > *To:* Repeater-Builder@ yahoogroups. com > < > http://us.mc560.mail.yahoo.com/mc/compose?to=Repeater-Builder%40yahoogroups > .com > < > http://us.mc560.mail.yahoo.com/mc/compose?to=Repeater-Builder%40yahoogroups > .com> > > >> > *Sent:* Sunday, February 28, 2010 8:49 PM > >> > *Subject:* Re: [Repeater-Builder] Micor Stock Power Supplies > >> > > >> > I've never heard of it. As an installer, I'm always under > pressure to > >> > use > >> > less expensive feedlines than the venerable Heliax, and I had > often > >> > considered LMR, but never actually succumbed to the temptation. > This is > >> > interesting information. Is this a well documented phenomenon? > >> > > >> > Anyone else like to chime in on this... > >> > > >> > Larry > >> > > >> > > >> > > >> > > >> > > >> > > > > > > > > > > ------------ --------- --------- ------ > > > > > > > > Yahoo! Groups Links > > > > > > > > ------------ --------- --------- --------- --------- --------- - > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 9.0.733 / Virus Database: 271.1.1/2728 - Release Date: > 03/07/10 > 02:34:00 > > > > > > > > > > > > > >
