1/2" or 3/8" LDF has always been my preference for jumpers, never had a problem related to a connector damage due to lack of flexibility causing over-stress at a connector, either at the antenna or at the main transmission line. Maybe there are some ham-grade antennas where a less-flexible jumper could pose a problem, but I've never had any problems with commercial antennas in this regard. Of course, for dipole arrays, yagis, and other commercial antennas that have built-in pigtails, this is a non-issue to start with, but for dishes, panels, fiberglass omnis (except for Sinclair and a few others that have pigtails), etc. that don't have integral pigtails, I'd never hestitate to use a 1/2" jumper. Most carriers still spec regular 1/2" jumpers AFAIK, including CommScope which is even stiffer than LDF.
Superflex has a thin jacket that can cause problems outdoors. The helical corrugation tends to let water spiral downward if you get a knick in the jacket. Yeah, it can be used outdoors, just be careful how it's dressed to ensure it can't rub against anything that might damage the jacket. --- Jeff > -----Original Message----- > From: Repeater-Builder@yahoogroups.com > [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Joe > Sent: Sunday, September 13, 2009 4:03 PM > To: Repeater-Builder@yahoogroups.com > Subject: Re: [Repeater-Builder] Re: coax cable > > > > We had thousands of 1/2" hardline jumpers connected to antennas at my > last job. It was the standard to use 1/2" LDF4-50A for the jumper. > > Joe > > MCH wrote: > > To reduce vibrations from the antenna being conducted to > the feedline. > > As it's not flexible, it will crack and/or break. I've also > seen cases > > where the antenna connector was vibrated right out of the antenna. > > > > Adding the flexible jumper acts as a 'shock absorber' and > absorbs any > > vibrations. > > > > That's why they include jumpers with commercial antennas. > > > > Joe M. > > > > Joe wrote: > > > >> OK, why? I've had this argument before......Joe > >> > >> MCH wrote: > >> > >>> Hardline/Heliax should *never* be connected directly to > an antenna. > >>> ALWAYS use a jumper. > >>> > >>> Joe M. > >>> > >>> > >> > >> ------------------------------------ > >> > >> > >> > >> Yahoo! Groups Links > >> > >> > >> > >> > >> ---------------------------------------------------------- > >> > >> > >> Internal Virus Database is out of date. > >> Checked by AVG - www.avg.com > >> Version: 8.5.387 / Virus Database: 270.13.38/2274 - > Release Date: 07/31/09 05:58:00 > >> > >> > > > > > > ------------------------------------ > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.409 / Virus Database: 270.13.78/2347 - Release > Date: 09/13/09 05:50:00 > > >