On 11/14/19 6:08 PM, Robert Harmon wrote:
Interesting stuff. I got on the Trilogy website, they have a corrugated copper
outer conductor too. Can't
find loss specs for lower HF freqs. Also suppliers and cost.
For HF, the loss is dominated by the skin effect in the shield and
center conductor - especially for hardline, which has almost no
dielectric. So the loss will go as sqrt(f). If the loss is, say,
10dB/ft at 10 MHz it will be 3.2 dB/ft at 1 MHz.
More details here:
https://www.microwaves101.com/encyclopedias/coax-loss-calculations
Bob
K6UJ
On Nov 14, 2019, at 12:57 PM, Michael Clarson <wv2zow@gmail.com> wrote:
Has anyone checked out Trilogy Cable? It is like catv Hardline, but 50 ohm.
Water migration is a non issue, cheaper than copper and tough as hell. The
Al outer conductor is pretty thick. As a bonus, it is made in USA.
On Thu, Nov 14, 2019, 13:58 Steve Maki <lists@oakcom.org> wrote:
LDF4 is the same as it always was.
It's the larger sizes where they are using a thinner shield. AVA5 took
the place of LDF5, AVA7 is the new 1-5/8", etc.
AVA cable has lower loss, but you can't drive a car over it like you can
LDF cable.
Still it's not THAT fragile - we've installed many thousands of feet on
cell towers and never had a problem.
OTOH RFS is still making the robust cable, and at a very good price, so
if you're buying new, it's a no brainer.
-Steve K8LX
On 11/14/2019 10:48 AM, Rob Atkinson wrote:
The feedback I get from industry now is that the Andrew (Commscope)
line is no longer of the quality it once was. The shield is thinner
and more fragile. The RFS Cellflex line is found to be better, like
the old Heliax. I have no first hand experience though because my
supply of old LDF4-50 and LDF4-75 are not yet used up.
73
Rob
K5UJ
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