Andrew has a coaxial cable similar (remarkably similar) to LMR, called CNT. I guess the same cautions apply to this product, too?
lh On Sun, Feb 28, 2010 at 9:22 PM, Mike Morris WA6ILQ <[email protected]>wrote: > > > Go here: > < http://www.repeater-builder.com/antenna/ant-sys-index.html> > > Scroll down to the article titled "Recommended Coax and Connectors > for the iDEN Enhanced Base Transceiver System". and read it, > and the one following it ("HELIAX Coaxial Cable for Low > Intermodulation Generation". > > Basically the Time Wire LMR series of cables (that's > a LMR followed by any 3 or 4 digit number) are not > long-term duplexable feedlines. They have an internal > construction that has aluminum foil rubbing against copper braid > and the dissimilar metals create desense. Also the center > conductor is copper clad aluminum. > > One of the kickers is that in many cases the noise problem > doesn't happen immediately - the cable works fine for a > while, then gets noisy, and the cable doesn't get immediate > attention - because "it's working fine". > > Mike WA6ILQ > > > At 04:26 PM 02/28/10, you wrote: > > What's the rationale behind the LMR ban? Leakage? > > lh > > On Sun, Feb 28, 2010 at 6:35 PM, Kevin Custer <[email protected]> wrote: > > > You wrote: > > Switchers -as a class- are more efficient and reliable than linear > supplies. > > As a Class... > More efficient - yes, More reliable - that's debatable. > > In the two-way radio world, linear supplies are the rule, switchers are > the exception. In 25 or 30 years, we'll see if switchers are 'really' > as reliable. In my experience with switchers (as a class), they are > hard on filter capacitors, with failures of them way before the normal > 'dry out' time - many times in just a few years. > > There are a few tower management companies that I know of that won't let > you install a switcher because of the possibility of interference. The > same companies also do not let anyone install LMR coax onto the site. > > I'll be interested to see the results too, Bob. > > Kevin > > > > > >
