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#48093 - 27/11/2001 11:57 Network wiring help needed please PLEASE PLEASE!!!
ShadowMan
addict

Registered: 09/06/1999
Posts: 559
Loc: Newfoundland, Canada
Ok... here's the deal.
Cat5 Wire comes from 3COM switch directly to PC wired as a straight through cable following any number of ways to wire straight through. (if that doesn't make sense it's because I have wired both ends of the wire multiple times. Both ends have always matched and worked)

Now if I take off the RJ45 connector on one end and punch the Cat5 into a Wall Jack using the same wiring layout. For arguments sake let's say I am using 568A on both ends. Oh and there are no patch panels invloved (that's another call for help later).

I plug in the computer to the wall jack using a known good patch cord (numerous patch cords actually) and I cannot get a link light. The computer no longer see a network and I am running around wimpering and now I am starting to crawl under desks and hide out. Can somebody please help me out here. What am I missing??? I even had the local telco guy drop by my office (thinking 2 heads are better then one) and we rewired everything and still no luck. HELP!!!

help.

Rene
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#48094 - 27/11/2001 12:48 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: ShadowMan]
bmiller
member

Registered: 11/04/2001
Posts: 150
Loc: Sacramento, CA, USA
Get a tester and test each point from the cumputer to the Swich.
Since you're not using a patch panel, it sounds really likely to be the line from the wall jack to the switch. The tester should tell you if you have pairs crossed. Get a nice one and it will even tell you which standard you are using.

I go with
WO|O|WG|Bl|WBl|G|WBr|Br
Hasn't let me down yet.
Maybe your RJ45s are not Cat 5 jacks?

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#48095 - 27/11/2001 12:53 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: ShadowMan]
robricc
carpal tunnel

Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
I don't see why that's not working, but this page might mention something you're missing.
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#48096 - 27/11/2001 14:22 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: ShadowMan]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31596
Loc: Seattle, WA
Just for ha-ha's, here's a few things to try:

- The computer in question... Try dragging it over to the destination hub/switch/whatever and try plugging it directly, using the same cable. Does it work?

- If not, try using a crossover cable. Does that work?

- Check the pins on the jack itself. Sometimes people plug telephone cords into network jacks. This bends the outer two pins badly and makes the connection work intermittently.

- In-wall and cable length? Not supposed to exceed 326 feet.

- Negotiation speed of NIC and Hub? Is it a 10/100 incompatibility? Even if both or either is supposed to be autosensing, I've had that kind of failure before and I was SURE it was a cabling problem until I throttled the NIC back to 10mbps and suddenly everything was fine.
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#48097 - 27/11/2001 14:24 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: ShadowMan]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31596
Loc: Seattle, WA
Also...

Did you wire these cables yourself?

When you do that, you have to use a certain pattern of wire pairs, and there is a certain pair that need to be intertwined to prevent crosstalk.

Sometimes a short cable run will tolerate incorrect wire-pairing, but it will begin to fail on long cable runs.
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#48098 - 27/11/2001 16:02 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: tfabris]
ShadowMan
addict

Registered: 09/06/1999
Posts: 559
Loc: Newfoundland, Canada
:(

Just for ha-ha's, here's a few things to try:
- The computer in question... Try dragging it over to the destination hub/switch/whatever and try plugging it directly, using the same cable. Does it work? - If not, try using a crossover cable. Does that work?


Yes It does work. I will try a crossover tomorrow with the wall box.

- Check the pins on the jack itself. Sometimes people plug telephone cords into network jacks. This bends the outer two pins badly and makes the connection work intermittently.

Jacks are new, have only been in my possession and I have checked them and they are fine.

- In-wall and cable length? Not supposed to exceed 326 feet.

About 30 feet total.

- Negotiation speed of NIC and Hub? Is it a 10/100 incompatibility? Even if both or either is supposed to be autosensing, I've had that kind of failure before and I was SURE it was a cabling problem until I throttled the NIC back to 10mbps and suddenly everything was fine.

10 Mb card going to a 3Com superStack II Autosensing Switch. Works fine when the Wall box isn't in the equation.

Did you wire these cables yourself?When you do that, you have to use a certain pattern of wire pairs, and there is a certain pair that need to be intertwined to prevent crosstalk.Sometimes a short cable run will tolerate incorrect wire-pairing, but it will begin to fail on long cable runs.

Yup, I used the 598A (iirc) standard and I also used whiteblue/blue whiteorange/orange whitegreen/green white brown/brown and I also used ....

This bites, I will try a crossover cable tomorrow and failing that I will break out the meter and trace the circuit boards to see what pin is going to which one in the connector. If it looks totally screwed up (as it did today with trying to follow the traces manually without a tester) I might just wire the wall box myself with a few wires and a bit of solder.
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#48099 - 27/11/2001 16:10 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: ShadowMan]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31596
Loc: Seattle, WA
Solder? Most wall boxes I know are simple punch-downs, with clearly labeled connection points which match the color coding on Cat5 wire. Perhaps you're just not using the proper kind of wall box?
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#48100 - 27/11/2001 16:19 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: tfabris]
ShadowMan
addict

Registered: 09/06/1999
Posts: 559
Loc: Newfoundland, Canada
They are the proper punch down type of wall boxes... trust me. By solder I mean on the back of the circuit board... right now there are 8 points where the cat5 wire is punched into the box. These 8 points (well not all 8) have circuit traces which lead to the pins that connect to the RJ45 port. I would cut the current traces and solder from pin 1 to pin 1, pin 2 to pin 2, etc. Right now I don't think they actually go from pin 1 to 1, 2 to 2 3 to 3 ...
I can take pictures and make a simple webpage if it would help you all to troubleshoot.
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#48101 - 27/11/2001 16:28 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: ShadowMan]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31596
Loc: Seattle, WA
Don't you have a pin continuity tester? You know, like this one.

If you're doing any network wiring yourself, you should own one of these at a bare minimum. This is a simple bare-bones continuity tester but it can show you if you have any pins swapped in situations like this.

In your particular case, you'd temporarily run a known-good long patch cable around the wall from the patch panel to the wall jack area, and test to see whether the wire pins were correct.

There are better cable testers which will check all sorts of great stuff like bandwidth and crosstalk. But they are more expensive. There are ones with remote bounceback modules for long-distance cable testing with a separate device at both ends.
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#48102 - 28/11/2001 05:40 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: tfabris]
ShadowMan
addict

Registered: 09/06/1999
Posts: 559
Loc: Newfoundland, Canada
Nope, nothing. I got me a cable crimper and I had a punch down tool. Now even the punch down tool is gone AWOL. I will have to try and get the right tools for the job. Hard to convince some people though (those above me) when everything I do for them works perfectly. It usually only seems to fool up when I am trying to do something to make my life a little easier, such as install two more network ports in my office. Sigh...
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#48103 - 28/11/2001 10:46 Re: Network wiring help needed please PLEASE PLEASE!!! [Re: ShadowMan]
hybrid8
carpal tunnel

Registered: 12/11/2001
Posts: 7738
Loc: Toronto, CANADA
A network tester is a must if you're doing this stuff on a regular basis.

My guess for your problem is the network panel/outlet you're using. They come pre-wired in a number of configurations - that aren't exactly marked in a straight forward manner either.

I had all sorts of headaches when helping a friend wire up a few new panels in his house. We were going crazy trying to figure out what the problem was. The new jacks weren't wired the same as the older ones. Older jacks required crossing the tx/rx and the new ones required just a straight connection. Take a closer look at the pcb.

Bruno
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#48104 - 05/12/2001 08:20 PCB layout figured out and attached... [Re: ShadowMan]
ShadowMan
addict

Registered: 09/06/1999
Posts: 559
Loc: Newfoundland, Canada
ahhhh... now just waiting for my punchdown tool to arrive.

The numbers indicate the punchdown slots and the letters indicate the RJ45 jacks.

(Transparent gif in order to make it look readable and small enough to upload with detail)


Attachments
47815-pcb.gif (93 downloads)

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#48105 - 09/05/2002 11:42 Re: PCB layout figured out and attached... [Re: ShadowMan]
ShadowMan
addict

Registered: 09/06/1999
Posts: 559
Loc: Newfoundland, Canada
Just to let everyone know that I got the tool needed (finally, though I was laid off for a while in between) and I finally have 2 more network jacks in my office thanks to that circuit trace I posted waaayyyy back.

Thanks for the advice.
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