[olug] DSL/CO distance in bellevue
olug at wjjeep.com
Wed Jan 4 18:42:22 UTC 2006
On Wed, Jan 04, 2006 at 04:19:11PM +0100, Charles Bird wrote:
> Speaking of signal level, do U know what a "good" signal to noise ratio is for the cable modem?
> I intend on taking off the cox supplied F connectors and replacing with my own in the unknown future.
> Those F connectors they use are kinda cool but if much flexing occurs it becomes loose and degrades the signal worse than the "super dooper sweeze till u bruise your palm" crimp-ons that I use.
> I am also looking into splitters. I have seen a few that offer less attenuation on one or more ports than other ports withing the unit itself. If I see it I'll post a link.
Some say that the hex crimp connecters are in fact worse as they don't provide a uniform crimp on the coax cable.
But I'm more concerned with the fact that you claim Cox connectors work themselves loose. First, what connection of Cox's are you moving around enough to work the connector loose, and secondly, can we be sure they have been terminated correctly by the Cox tech? The compression connectors they use should be extremely strong if installed correctly. In fact, compression connectors like Thomas & Betts Snap-N-Seal should be stronger than the hex crimp-on type.
As far as attenuation goes, compression fittings should be better:
"A few differences between hex-crimp and compression connectors. Hex-crimp creates 6 points of impedance mismatch, which, are 6 points of signal reflection. Reflections can cause standing wave (analog) and/or packet collisions (digital). Return loss is also much better with compression connectors (>30dB vs upper teens for hex-crimp)."*
Also see: http://www.tecratools.com/pages/tecalert/tooling_solutions.html
As far as your question about good s/n ratios: http://www.dslreports.com/faq/cableuser?text=1 (greater than 30)
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