A minor detail: Heliax does not use annular corrugation. A long time ago,
KabelMetal/RFS owned Phelps Dodge which came to be called Cablewave.
Cablewave needed to make a line of coax to compete with Heliax but it had
to be annular and not helical. They have been playing catch up ever since
on coax as well as elliptical waveguide. And parabolic dishes. Cablewave
makes fine product and is just as worthy as the bigger name brand. They
make foam dielectric and larger types of mainly air dielectric for those
that need the lowest of loss and have the money for it. They also do rigid
coax that measure in the inches with EIT connectors. I doubt the
connectors are interchangeable with those for Heliax.
Al
N6TA
On Sat, Sep 14, 2019 at 9:28 AM Steve Davis | Davis RF <sdavis@davisrf.com>
wrote:
>
>
> ________________________________
> Bob, 1/2" RFS Cellflex Tm is not as flexible as the name might imply.
> It is not good for rotor loops unless you use a loop that is far longer
> than what length you would use for say a LMR-400 UF or Belden 9913F7 (their
> Belden being preferable for a number of reasons)
>
> 1/2" RFS Cable Wave Systems
> Cellflex Tm IS, in fact, hardline. It uses an annularly corrugated
> outer copper shield, same as Heliax.
>
> At 20 M. the attenuation is low for many cable choices. Also, if you
> chose Cellflex, you would want to use a rotor loop of 9913F7, etc.
> Splicing that in with two connectors and a barrel adaptor, CONTRARY to
> popular belief, is going to create such a low insertion loss, that there
> will never be any perceptible negative factor to any receive or transmitted
> signal. I'm talking less than .002 dB (at the MUF of the connector, 300
> MHz is the MUF for our UHF connectors) using our commercial connectors.
>
> As I stated in the email to you this a.m, which crossed in the mail with
> your posting here today, I will get back to you with facts, details,
> alternatives and lower costs than 1/2" RFS
> 73 Steve K1PEK, Snr. Cable Design Engr/Founder, DAVIS RF Co.
>
>
> >
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>
>
> ------------------------------
>
> Message: 8
> Date: Sat, 14 Sep 2019 08:47:52 -0700
> From: Robert Harmon <k6uj@pacbell.net>
> To: towertalk@contesting.com
> Subject: [TowerTalk] Cell Flex cable question
> Message-ID: <5C2910DF-EAD9-4F29-8E2C-492CE3ADAD90@pacbell.net>
> Content-Type: text/plain; charset=us-ascii
>
>
> Have you used Cell Flex cable from Davis RF ? Looking for feedback on
> this cable. I am thinking
> about replacing a 300 foot run of RG-213 from my shack to a 20M yagi with
> 1/2" Cell Flex. . It looks like it would
> give me approximately 1.8 db less loss for a 300 foot run if I figured it
> out correctly. Much cheaper than hardline.
> I am wondering if it is flexible enough to used in a rotator loop so I
> wouldn't need to use a section of more flexible
> cable for the loop ?
>
> Bob
> K6UJ
>
>
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> End of TowerTalk Digest, Vol 201, Issue 41
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