I find this interesting, especially Bill K4XS' comments. My comments...
LMR400UF has a thermoplastic elastomer jacket that is good for
"in excess of 10 years" outdoors. Most of the other LMR400s use a
PE or PVC jacket that're supposedly good for 20 years outdoors.
Apparently, Times' marketing department is... ahem... stretching
the truth a bit!
I've used the DX Engineering DXE-400MAX and Davis RF BuryFlex400 stuff.
It has a Type III PE jacket and has been fine for nearly 10 years
(so far). In another 10 years, I'll let you know if it lasts 20 years. ;-)
vy 73,
Bryan WA7PRC
Date: Tue, 26 Mar 2013 11:42:22 -0400 (EDT)
From: Bill K4XS
Subject: Re: [TowerTalk] LMR degradation
Back in the early 2000s I had a long conversation with the guys
at Times. The ultra flex on many of my jumpers had cracked after
only a couple of years in the FL sun. His response was the
ultraflex was not supposed to be used outside.
He offered to replace the stuff with regular 400 but I never
took him up on it.
I use the regular LMR 400 on all my jumpers and have had zero problems.
Bill K4XS
Roger K8RI writes:
We've known for years the UF versions of the LMR cables deteriorate out
in the elements. It follows that they'd possibly do so with age as well.
I found that the braid had almost disentegrated in some pieces of
LMR400UF where the jacket "appeared" to syill be in good shape. I
thought perhaps the jacket had become porous, but perhaps not? I wonder
which LMR400 he's talking about.
73
Roger (K8RI)
> On 3/24/2013 9:42 PM, Jim Hoge wrote:
>> Today I discovered that I have had environmental ingress beneath the
>> outer jacket of some ~8 year old LMR-400.
>>
>> In the latest (I think) version of his excellent Managing Interstation
>> Interference," W2VJN notes that he observed degradation in the measured
>> performance of stubs made of LMR400 that had been sitting in his garage
>> for a bit less than a decade. He seemed to think it was due todegraded
>> contact between the foil and braid shields. This was written several
>> years ago. He may have more to say about it by now.
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