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Rod Maupin October 11th 06 12:43 AM

Coax Standoffs
 
I'm planning on putting up a tower and a question I've always had is about
coax standoffs. Are they necessary?



Dale Parfitt October 11th 06 02:11 AM

Coax Standoffs
 

"Rod Maupin" wrote in message
...
I'm planning on putting up a tower and a question I've always had is about
coax standoffs. Are they necessary?
I am hoping this is just a troll.




Rod Maupin October 11th 06 02:32 AM

Coax Standoffs
 
I'm actually serious and I don't know the answer or I wouldn't ask.

I've seen both cases. Some people use them, some don't. What is the
advantage of using them?



Richard Clark October 11th 06 04:35 AM

Coax Standoffs
 
On Tue, 10 Oct 2006 18:32:03 -0700, "Rod Maupin"
wrote:

What is the advantage of using them?


Hi Rod,

Strain relief, which, by the way, can be achieve by simply strapping
it to the tower.

Downside: creates a voltage standoff too in the event of lightning
strike. This is solved by the alternative offered in the paragraph
above (grounding implied).

73's
Richard Clark, KB7QHC

[email protected] October 11th 06 04:48 AM

Coax Standoffs
 
I'm actually serious and I don't know the answer or I wouldn't ask.
I've seen both cases. Some people use them, some don't. What is the
advantage of using them?


I don't recall you mentioned that you were ALSO putting up a tower, so
IF, for example, your coax is running up the side of your house and
then across the roof, another answer is "to keep the coax in place"
vs. letting the wind slid it across the roof.

--
--Myron A. Calhoun.
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
NRA Life Member and Rifle, Pistol, & Home Firearm Safety Certified Instructor
Certified Instructor for the Kansas Concealed-Carry Handgun license

Sal M. Onella October 11th 06 04:49 AM

Coax Standoffs
 

"Rod Maupin" wrote in message
...
I'm planning on putting up a tower and a question I've always had is about
coax standoffs. Are they necessary?


No. If somebody used standoffs for coax, it was probably money wasted.
Coax can be secured directly to the mast or tower, coiled on itself, and
even buried (some types). It could even be tied in loose knots without
having its electrical properties affected. You just can't crush it or bend
it tighter than the bend radius specified for the cable.

Open wire line and TV twinlead must be kept away from metallic structures
and not coiled. That's what you use standoffs for.

In a few cases, some form of standoff might be used when the coax forms a
rotor loop, but such use is strictly mechanical.

73
"Sal"



Rick Frazier October 11th 06 07:47 AM

Coax Standoffs
 
Another thing to consider is if the individual has a crank-up tower.
The rather longish "standoff" on the top of the upper section of the
tower is to keep the coax from getting fouled (and perhaps damaged) when
the tower is cranked down. However, on re-reading the original post, it
sounds like the question was about the little (6" perhaps) standoffs
which are typically used for twinlead...

[sigh] OH... That's different... Never Mind....

Rick AH7H


Sal M. Onella wrote:
"Rod Maupin" wrote in message
...

I'm planning on putting up a tower and a question I've always had is about
coax standoffs. Are they necessary?



No. If somebody used standoffs for coax, it was probably money wasted.
Coax can be secured directly to the mast or tower, coiled on itself, and
even buried (some types). It could even be tied in loose knots without
having its electrical properties affected. You just can't crush it or bend
it tighter than the bend radius specified for the cable.

Open wire line and TV twinlead must be kept away from metallic structures
and not coiled. That's what you use standoffs for.

In a few cases, some form of standoff might be used when the coax forms a
rotor loop, but such use is strictly mechanical.

73
"Sal"



Wes Stewart October 11th 06 07:48 PM

Coax Standoffs
 
On Tue, 10 Oct 2006 16:43:25 -0700, "Rod Maupin"
wrote:

I'm planning on putting up a tower and a question I've always had is about
coax standoffs. Are they necessary?


With a crank-up tower, maybe. Otherwise, no.


art October 16th 06 10:21 PM

Coax Standoffs
 
Rod
I see they are giving you a hard time. Stand offs are used on Andrews
coax when the coax is used as an antenna and you will see them in
tunnels or industrial areas to ensure communication to the home base.
The copper sheathing which is not visible because of the plastic
covering is perforated down one side and must be placed away from any
metal surface
Regarding your tower, the coax must always be grounded at the top of
the tower as well as the bottom and it is always advisable to have the
coax floating INSIDE the tower so in those circumstances a standoff is
useful. I'm guessing that putting the coax inside the tower is to
protect it from lightning strikes and I suppose if the coax sheathing
was stranded it would be to prevent cross talk between cables. I seem
to remember that Tom Rauch has some comments about this on his page and
is much more knoweledgable about these things than those who frequent
this newsgroup. As an aside if your tower is a new one check out the
drainage aspects, we had a local guy die because the bottom rusted thru
while he was up there and offcourse the rust was not visible on the
outside
Regards
Art

Rod Maupin wrote:
I'm actually serious and I don't know the answer or I wouldn't ask.

I've seen both cases. Some people use them, some don't. What is the
advantage of using them?




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