[TowerTalk] hardline bending radius

[Jim Thomson]

Date: Tue, 20 Nov 2012 07:50:44 -0500
From: Steve Maki <lists at oakcom.org>
To: towertalk <towertalk at contesting.com>
Subject: Re: [TowerTalk] hardline bending radius

On 11/20/2012 4:54 AM, Jim Thomson wrote:
> Date: Mon, 19 Nov 2012 13:35:01 -0500 (EST)
> From: K7LXC at aol.com
> To: towertalk at contesting.com, jimlux at earthlink.net
> Subject: Re: [TowerTalk] hardline bending radius
>
>>> I recollect that the minimum bending radius for all coaxes is 6
> times
>> the diameter. For 1/2" RG-8, that'd be 3 inches.
>
>
>> I think that's for coax with braided shield (the RG-8, RG-213) kind.
>
> It's an Andrew standard for their non-braided coaxes.
>
> Cheers,
> Steve K7LXC
> TOWER TECH

> ## as a side note, if RFS brand heliax is used, the turning radius is one heck of a lot less
> than Andrew heliax. The RFS stuff uses a corrugated cu center conductor as well as the
> either cu or AL corrugated shield. Andrew heliax uses a copper tube on it?s 7/8? heliax...
> and also on its 1.25? heliax. The RFS stuff is flexible. IF you get the version with the
> AL corrugated shield, it?s also very very light. That AL outer shield version only comes
> in 2 sizes, 7/8? and also 1.25? . It?s a lot cheaper than andrew....esp if you get it at Davis RF.
> And of course, 7-16 Dins are readily available for both sizes. The RFS stuff is a heck of a lot
> easier to work with.
>
> later........ Jim VE7RF

That's a bit of over-generalization. Both RFS and Andrew make standard 
and flexible versions of their cables. The construction is virtually 
identical on comparable versions.

-Steve K8LX

##  since when did andrew start making  7/8”  and  1.25”  heliax with  corrugated center conductors ?? 
That andrew “flex” version  of 1/2”  heliax is nothing more than a corrugated shield, making a sloppy fit 
over the  dielectric.  All the andrew 7/8”  +  1.25”  heliax  I have ever seen always had a copper tube
in the center... = zero flex.  

##  I see andrew blathering on about the 1st to use corrugated aluminum for the shield, but have  yet to
see any andrew hekiax with an AL corrugated shield.   Copper is 2-5% heavier than steel and almost triple
the weight of aluminum.   That RFS heliax with the corrugated  AL shield + CU corrugated center conductor
is the real deal.... super light,and super flexible, with no where near the turning radius of standard andrew
offerings. 

##  that  ‘superflex’  andrew 1/2”  heliax is spec’d to be rolled and unrolled X many times off a cable reel, that’s it. 
It uses Cu clad solid AL for the center conductor. Nick the CU..and you are in a real mess, esp if you ring it 360 degs.
That CU copper tube used on the andrew 7/8” and 1.25”  heliax is no fun to work with...pita. You can have it.

Later...... Jim   VE7RF