On 30 Nov 2005 02:51:01 -0800, "jim_in_sussex"
wrote:


Andy Hall wrote:
On 29 Nov 2005 12:41:37 -0800, "jim_in_sussex"
wrote:

About to instal broadband.

Q1 Assuming that is OK, which are the correct colours to use in the
CAT5 cable?


The first pair used is normally the blue.

TFT

....
Q2 Is it correct that each RJ45 socketed ethernet channel on the router
only require 3 wires ? If so, can the unused 6 wires in the CAT5 cable
be used to feed a RJ45 socket to the router? - if so, which cable
colours carry the signals?

Ethernet requires 4 wires, so this would leave two pairs unused.

You might get away with what you are suggesting, but it is bad
practice to mix services in one cable. It might not cause a problem
at 10Mbits, but if the link is set or negotiates to 100Mbit, then
there is a fair chance that the ethernet will run unreliably.

Understood - but it's going into my parents home & is only being
installed for convenience when visiting, not posterity. However given
what you say, What is the best choice of cable?

requirements a

A) to take the unfiltered AB signal downstairs (about 25m) (all speech
telephone cables being filtered off at the entry point) - essential

B) Take a new speech telephone cable to near the router from the filter
point. - useful only

C). Bring back part way (to 1st floor) a CAT5 cable to carry ethernet
to/from the router. - high up in the wants.


For A) is CAT5 really needed?

No it isn't.

Won't ordinary telephone cable do?

Yes, although if you're having to buy a reel, then it may be cheaper
to just get one cable type.


After all the signal travels unfiltered 3/4mile or more from the
exchange on normal BT cable.

For B) ordinary telephone cable will do, but if that is OK for A) & I
try to use the same (6 way) cable as for A then is there a risk of
cross-talk?

It's unpredictable. That's really the issue. You could put it in
and it might work and then not and be intermittent. It's much easier
to thread two or more cables while you're at it than to have to go
back.



For C) clearly a dedicated CAT5 is what you're recommending - will do

There's something I don't understand here - why is CAT5 the standard
cable when apparently only half the cable is used (4 wires out of 8)?

Other pairs are used for other purposes but not at the same time down
one cable.



Also what are the standard pairings on CAT5 for sthe standard PC router
ethernet signals?

There are two standards for the cable wiring

http://www.memex.ca/support/referenc...t%20Wiring.htm

obviously the pin numbers on ethernet remain the same.

Another thought if you don't want the cable hassle is to go for
wireless. There are some good bundle deals on 802.11g and even Pre-N
products.







++++

Other posters have mentioned the Clarity master filter which is the one
I will be installing on this job. One is already in use in my own home
& it works just fine - my home system cabling splits into separate
speech and ADSL networks at the front door. Highly recommended.

--

..andy