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Bennett Price Bennett Price is offline
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Default Creases in coaxial cables

Sorry - I don't have a clue as to what these markings mean.
It's labeled 200896 F677TSVV (ETL) us CATV 18 AWG




mm wrote:
On Fri, 15 Dec 2006 16:57:57 GMT, Bennett Price
wrote:


mm wrote:
Are small bends, or even small creases, or even large creases enough
to cause internet signal degradation. IIUC, it can cause ghosts in tv
reception??, but with internet, it would mean the resending of some
packets, right. Perhaps multiple resending, lowering the speed by 10,
20, 50, 80%????

When my isp starts to offer cable internet, I'm hoping to sign up. I
would run the cable from the back of the house to the office, using if
I can, scrap coaxial cable. It's in very good condition, beautiful
ends on each end (better or at least better looking than I can
attach), bright white finish, never been dirty, but it has been bent
at one or two places to a 90 degree angle, and at 3 or 4 other places
to a 135 or 120 degree bend. Of course there is no flex pressure on
the cable now, and I have bent the coax back to where it is
practically straight when it is at rest (and not coiled). I'm
guessing that maybe the insulation was compressed, and the distance
from the center wire to the shield is not as great as it should be in
these two locations. Maybe 10 or 20% too little on one side of the
wire. Is that enough to lower transmission speed??

Even if you tell me this is imporant and I should get new cable, what
about using this cable for other things, like running tv around my
house or things I don't even know about. Does what I described mean
there will be a substantial signal loss, or ghosts??

Thanks

If you are inclined to email me
for some reason, remove NOPSAM :-)

Do you have some TV application that would let you test the cable,
however imperfectly. Perhaps from VCR to TV, comparing your cable to
a brand new 6' long cable. Not a perfect test as channels 3 and 4 are
less than 100MHz but if the long cable is visibly inferior, you know
you should scrap it.


What a great idea (and should-be obvious idea to me who has often
said, The way to know is to look.) I should have thought of this.

I'll do that.

But as others have noted, the RG # of the cable is all important.


It's labeled 200896 F677TSVV (ETL) us CATV 18 AWG .

Could you explain any of thta to me?

After my first post I remembered that I had cable tv for a few years
when I moved in, and the cable guy scrunched up about 12 inches and
stuffed it into a 3 inch box, with some pretty sharp bends. When I
learned how bad this was, I can't remember which: either I didn't have
cable anymore, or I would have complained, but the cable picture was
perfect afaict. Regardless of the reason I didn't complain, the cable
picture was perfect as far as I could tell.

If you are inclined to email me
for some reason, remove NOPSAM :-)