I second Roger's comment. Coax I removed from a large stack were 7/8
hardline to LMR600UF swing arm loops, and the 600 was in bad shape after
7 years. Several cuts, one complete tear of the braid, water inside.
I'm using Buryflex service loops and with 7/8 LDF5 for 20/15/10 and 1/2
LDF4 80 & 40 have less than 0.8db loss Yagi feedpoint to amp on all
bands. Buryflex is very tough stuff and flexible enough for service
loops. With the long runs (140' tower, 125' to shack) in hardline the
slight additional loss for the short service loop is within the loss
budget.
Grant KZ1W
On 7/31/2015 23:44 PM, Roger (K8RI) on TT wrote:
I use, or have used a lot of LMR 600. I much prefer the crimp on
connectors...HOWEVER LMR 600 UF is not recommended for exterior use.
I have used the UF versions of LMR 400 and 600. The best life I've
gotten out of them has been 6 years although it's rated at 10 years.
The jacket is rubber like, easily abraded, and does not stick to the
shield. A three turn coil of LMR 400UF laying on the flat plate top
of a 45G wore through to expose several sections of shield 3 or more
inches long. It does not appear to stand up well to UV light and that
is at 43', 37" N. OTOH it is the most flexible large coax I've used
73
Roger (K8RI)
On 7/31/2015 8:43 PM, Robert Harmon wrote:
I have a 380 foot coax run to the top section of my motorized tower
when it is fully extended.
I am changing out all my old RG213 and thinking of saving a few db by
going to LMR600 up to the top section then
LMR400UF up from there for the rotor loop and up to the 40 meter beam
and triband/warc beam on the mast.
What do you think of LMR600 for this run from the shack up to the top
section for a motorized tower ?
When I lower the tower I am thinking I could coil the LMR600 into
maybe 5 foot diameter coils on the ground.
BTW the tower is 90 feet to the top of the top section when all the
way up.
Is this a bad idea ? (I am hoping to avoid the cost of the flex
LMR600UF if I can.)
A side issue is I understand I have to be very careful not to nick
the copper clad on the center conductor
when installing a connector on the non flex LMR600. I would use the
Davis PL259 connectors for LMR600. Anyway maybe this usage of the
LMR600 is not a good idea, what do you think ?
Bob
K6UJ
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