I have a length of rg-58/u which was rolled up and when unrolled has
revealed some kinks. Has anyone any idea on how to smooth things out
again. It shows good on my analyzer, and I'm not worried about a bit
of migration which may have taken place. A bit of loss is of no real
concern to me. Someone suggested letting it rest in a tub of hot water
for a while, but that is the only suggestion so far.

Thanks in advance for any assistance,

Irv VE6BP

On 10/18/2014 9:28 AM, Irv Finkleman VE6BP wrote:
I have a length of rg-58/u which was rolled up and when unrolled has
revealed some kinks. Has anyone any idea on how to smooth things out
again. It shows good on my analyzer, and I'm not worried about a bit
of migration which may have taken place. A bit of loss is of no real
concern to me. Someone suggested letting it rest in a tub of hot water
for a while, but that is the only suggestion so far.

Thanks in advance for any assistance,

Irv VE6BP

My first suggestion is to lay it in the midday sun an allow it to warm
for an hour or more. Then uncoil it and allow it to relax a bit longer.

My garden hose responds to that treatment.

Good luck.

John

On Sat, 18 Oct 2014 08:28:26 -0600, Irv Finkleman VE6BP
wrote:

I have a length of rg-58/u which was rolled up and when unrolled has
revealed some kinks. Has anyone any idea on how to smooth things out
again. It shows good on my analyzer, and I'm not worried about a bit
of migration which may have taken place. A bit of loss is of no real
concern to me. Someone suggested letting it rest in a tub of hot water
for a while, but that is the only suggestion so far.

As long as the kinks are only in the outer jacket, I wouldn't worry
about it. However, if it appears that the braid is also kinked or
wrinkled, you might be right about the center wire migration. If you
have a TDR (time domain reflectometer), it will show an impedance bump
where the center wire has moved. Such cold flow tends to happen with
RG-58a/u solid center conductor cable and low loss foam dielectric.
I've only seen it once and you have to roll it into a really small
tight coil before that will happen. It also requires rigidly attached
coax connectors to produce migration. (Open coax ends just cause the
center wire to telescope in and out).

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

"Irv Finkleman VE6BP" wrote in message
...
I have a length of rg-58/u which was rolled up and when unrolled has
revealed some kinks. Has anyone any idea on how to smooth things out
again. It shows good on my analyzer, and I'm not worried about a bit
of migration which may have taken place. A bit of loss is of no real
concern to me. Someone suggested letting it rest in a tub of hot water
for a while, but that is the only suggestion so far.

Go up to the kink, and treating it as though it is still rolled around the
former, unroll it.

On Sat, 18 Oct 2014 18:41:24 +0100, gareth wrote:

"Irv Finkleman VE6BP" wrote in message
...
I have a length of rg-58/u which was rolled up and when unrolled has
revealed some kinks. Has anyone any idea on how to smooth things out
again. It shows good on my analyzer, and I'm not worried about a bit
of migration which may have taken place. A bit of loss is of no real
concern to me. Someone suggested letting it rest in a tub of hot water
for a while, but that is the only suggestion so far.

Go up to the kink, and treating it as though it is still rolled around
the former, unroll it.

Once unrolled as to unwind any kink, stretch the length of coax between
two supports for a few days and allow the sag to stretch the coax back.

Irv Finkleman VE6BP wrote:
I have a length of rg-58/u which was rolled up and when unrolled has
revealed some kinks. Has anyone any idea on how to smooth things out
again. It shows good on my analyzer, and I'm not worried about a bit
of migration which may have taken place. A bit of loss is of no real
concern to me. Someone suggested letting it rest in a tub of hot water
for a while, but that is the only suggestion so far.

Thanks in advance for any assistance,

Irv VE6BP

OK guys, thanks for the input.
First a couple comments -- my 'yard' is a 6x10 foot third floor deck and
the yard is not accessible. I could not use the deck only because it
faces south and the apparent movement of the sun across the sky leaves
different and changing portions in the shade.

I wasn't worried about a leaking coax as it looked quite new, and
tested good on my MFK-259 Analyzer.

I decided that all factors considered I would give it a good soaking
in hot water in the sink, changed frequently to keep it hot. The
cable ends were kept out of the water.

I kept the water hot for 6 hours or so, and the cable came out feeling
quite supple and appearing kink free. It lay on the floor like wert
spaghetti, and it still tests good on the analyzer.

It's only a short length -- maybe 25 ft with PL-259s on the end, and
it was given to me free, so could easily have gone and bought some,
but ham radio is ham radio, and free coax with fittings is always
welcome. Now I can store it away properly coiled so that if I ever
do need it, it won't be a problem. Murphy (of Murphy's Laws), who lives
with me, tells me I'll never need it again in 100 years!

I guess it it had been an RG-8 variety, I would have had to use the
bathtub!

Thanks again all, it was an interesting experiment.

Irv VE6BP

"Irv Finkleman VE6BP" wrote in message
...

Irv Finkleman VE6BP wrote:
I have a length of rg-58/u which was rolled up and when unrolled has
revealed some kinks. Has anyone any idea on how to smooth things out
again. It shows good on my analyzer, and I'm not worried about a bit
of migration which may have taken place. A bit of loss is of no real
concern to me. Someone suggested letting it rest in a tub of hot water
for a while, but that is the only suggestion so far.

Thanks in advance for any assistance,

Irv VE6BP

OK guys, thanks for the input.
First a couple comments -- my 'yard' is a 6x10 foot third floor deck and
the yard is not accessible. I could not use the deck only because it
faces south and the apparent movement of the sun across the sky leaves
different and changing portions in the shade.

I wasn't worried about a leaking coax as it looked quite new, and
tested good on my MFK-259 Analyzer.

I decided that all factors considered I would give it a good soaking
in hot water in the sink, changed frequently to keep it hot. The
cable ends were kept out of the water.

I kept the water hot for 6 hours or so, and the cable came out feeling
quite supple and appearing kink free. It lay on the floor like wert
spaghetti, and it still tests good on the analyzer.

It's only a short length -- maybe 25 ft with PL-259s on the end, and
it was given to me free, so could easily have gone and bought some,
but ham radio is ham radio, and free coax with fittings is always
welcome. Now I can store it away properly coiled so that if I ever
do need it, it won't be a problem. Murphy (of Murphy's Laws), who lives
with me, tells me I'll never need it again in 100 years!

I guess it it had been an RG-8 variety, I would have had to use the
bathtub!

Thanks again all, it was an interesting experiment.

Irv VE6BP
^^^^^^^^^^^^^^^^

Glad it worked out for you Irv. And I hope you are getting your small space
antennas up and effective.

Wayne
W5GIE/6

Unless there is something special about this coax, or if you are just going to use it for a television antenna, or something that you are only going to receive on - THROW IT AWAY!

once you exceed the minimum bend radius you open up the braid and the coax is never the same again.
THROW IT AWAY!

Coax has a shelf life - for example, Belden 9913 has a shelf life of about 10 years. Even though it was never exposed to sunlight and it was never taken out of the shed and was never exposed to the elements, after about 10 years, the coax starts to degrade and break down and then it is junk.

The kind of stuff you see at a swap meet, where the owner is still trying to get top dollar out of it.

Good Coax pays huge dividends in performance.

If all you are going to do is hook it up to a Ringo Ranger and put it on a tower, above the garage door of a fire station, and the county repeater is only 2 miles away, then yes - the quality of the coax doesn't matter much - other then the fact that it might show a false VSWR.

Like others has said, there is no way to predict what will happen when you go to use it unless you attach it to a Time Domain Reflectometer and sweep it! Something I doubt most hams would have - unless they work in the cellular telephone industry.

On Sunday, October 19, 2014 10:29:29 AM UTC+11, Brian Reay wrote:
John S wrote:

On 10/18/2014 9:28 AM, Irv Finkleman VE6BP wrote:

I have a length of rg-58/u which was rolled up and when unrolled has

revealed some kinks. Has anyone any idea on how to smooth things out

again. It shows good on my analyzer, and I'm not worried about a bit

of migration which may have taken place. A bit of loss is of no real

concern to me. Someone suggested letting it rest in a tub of hot water

for a while, but that is the only suggestion so far.



Thanks in advance for any assistance,



Irv VE6BP



My first suggestion is to lay it in the midday sun an allow it to warm

for an hour or more. Then uncoil it and allow it to relax a bit longer.





I've used this technique on a real hot (for the UK) summer's day and found

it worked well, the only difference is I popped it in the airing cupboard

for 24 hrs first rather than leaving it in the sun. I then unrolled it on

my drive in mid afternoon, when the block paving was noticeably warm. The

cable was noticeably 'subtle' and the kinks came out easily. I rolled onto

a drum, with a tail free at the core, to aid checking. (So I could short

the end or terminate it etc. while applying a VNA to the free end.) I had

to 'snake' the cable to fit it on the drive.



Testing indicated the cable was within spec., at least to the limits of my

test equipment (said VNA and Bird power meter etc.)



I would not recommend either hot water or 'stretching'. Water ingress is

and obvious issue and stretching could change the dimensions.



You could, perhaps, use a hair dryer on a bad kink but I would be cautious.

I would probably write off that section. A heat gun would certainly be a

bit too hot, in my view. You don't want to damage the jacket or change the

dimensions.



The cable I recovered was double screened and worth saving, it had been

loose coiled by someone and picked up at a rally, with some matching

connectors for peanuts. Sadly, it wasn't 'fox proof' and one of the local

foxes decided to chew through it when I used it for long, experimental,

feeder run one winter. All part of life's rich tapestry.



73

Brian

G8OSN/W8OSN

www.g8osn.net

I know you were talking about coax, but I had a really good chuckle at the "noticeably warm" and "for the UK" comments. Thanks!

wrote in
:

I know you were talking about coax, but I had a really good chuckle at
the "noticeably warm" and "for the UK" comments. Thanks!



Beleive it, it gets warm here. I have photos of thermometers to prove 53°C
in a back yard in Bristol. Temperatures normally found only occasionally,
even in India, or Death Valley in Arizona. It's probably a lot more common
than people think, it doesn't take much strong sunlight to do it if there's
shelter from wind. Anyone who owns a car knows that leaving a child or pet in
one on a summer day is a death sentence. (Very few do not, but they usually
find out the hard way, as occasional news reports show).