Topband: Fsj4 series heliax around a rotor

[Mike/W5JR]

One option is to do what remote ENG trucks do and make at least a 540 deg or 720 deg (1.5 or 2.0 or more) loops rather than a 180 or 360. This will reduce some of the flexing action as it is more like changing the coil size instead of a lot of bending back and forth.

You do need to be careful in prepping the ends for connectors. It is very easy to score the thin copper shield and it will fracture easily if scored. I recommend using some of the heat shrink with the glue inside on the back of the connector shell and down the cable three or four inches to act as a strain relief. 

tnx
Mike / W5JR
Alpharetta GA

> On Jun 8, 2014, at 1:17 PM, "Carl" <km1h at jeremy.mv.com> wrote:
> 
> What is this antenna, tower, rotator, and cable configuration?
> 
> Im also using 5 cables and around a Tailtwister rotator.
> 
> Carl
> KM1H
> 
> 
> ----- Original Message ----- From: "Peter Voelpel" <dj7ww at t-online.de>
> To: <topband at contesting.com>
> Sent: Sunday, June 08, 2014 10:45 AM
> Subject: Re: Topband: Fsj4 series heliax around a rotor
> 
> 
>> I turn 1/2" Cellflex cable which is similar to FSJ4 for more then 30 years
>> and never had a problem.
>> On one tower I turn a bunch of 5 cables at once.
>> 
>> And yes, never damage by critters since using that kind of cable on all
>> bands, also as feed lines for beverages.
>> 
>> 73
>> Peter
>> 
>> -----Original Message-----
>> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Carl
>> Sent: Sonntag, 8. Juni 2014 15:33
>> To: jim at audiosystemsgroup.com; topband at contesting.com
>> Subject: Re: Topband: Fsj4 series heliax around a rotor
>> 
>> More of a topic for a VHF/UHF forum where the question comes up often..
>> 
>> I use that coax on the mast and to power dividers and out to individual
>> yagis but it certainly is not meant to survive long around a rotator. There
>> I use LMR400UF and into a 50-75 Ohm coax line transformer into .75 to 1" 75
>> Ohm CATV hardline for 144 MHz and higher.
>> 
>> Another line transformer converts back to 50 Ohms in the house to keep the
>> several Bird 43 line sections and elements happy.
>> 
>> Carl
>> KM1H
>> 
>> 
>> ----- Original Message ----- From: "Jim Brown" <jim at audiosystemsgroup.com>
>> To: <topband at contesting.com>
>> Sent: Saturday, June 07, 2014 11:09 PM
>> Subject: Re: Topband: Fsj4 series heliax around a rotor
>> 
>> 
>>> This would be a natural topic for Tower Talk.  Access via contesting.com
>>> 
>>> 73, Jim K9YC
>>> 
>>>> On 6/7/2014 7:03 PM, Bill Wichers wrote:
>>>> I'm thinking about replacing the lmr400 with fsj4-50b heliax since I have
>> 
>>>> several thousand feet of that on a reel. I'm also thinking that the
>>>> corrugated copper shield will resist critter damage better than the braid
>> 
>>>> in the lmr400 cable.
>>> 
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