Ive been networking around where Im currently working, it is not your normal environment to say the least...lets say there is a LOT of EM waves going around here. Depending on where i run the cable, and how long, my connections are intermittent, and I generally have to make shorter cables to get things done, needless to say, I dont have the hardware to go hub-hub here, unfortunately, and 3coms claims to work are obsurd...not sure if its caused by the environment here, but its happening, Im a long time networker, have been networking for about 6-8 years now, give or take, I have 2 reels of cable here, all unshielded, but I am not sure if shielded would help, Im assuming that EM interference is causing the bulk of my problems, but I have no way to test or validate this theory, because some different cabling that was running before seems to run longer distances, not much but a little, any ideas? thoughts? Im goona query some other network guys on this base tonight, but...when I cant run a 50-120 ft cable without having problems, something is up. Never seen anything like it, any thoughts and/or ideas would be appreciated.
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Cat 5 cable signal loss?! cable less than 50 ft? 2
- Thread starter Rayek
- Start date
daronwilson
Vendor
The 1-2 and 3-6 pairing thing is of critical importance. We've discussed it many times in this forum, but here it is briefly again.
Ethernet on UTP wiring uses two pairs. One 'pair' is the transmit, one is the receive. It is important that a twisted pair of wires is used on pins 1 and 2, and equally important that a twisted pair of wires is used on pins 3 and 6. Often I find cables made up just like a USOC plug, or just some non-standard color code. As long as you actually have a pair on each pin pair listed it really doesn't matter to the ethernet connectivity what the color of the jacket is. However, there is really no reason to wire a plug or jack any other way than an approved standard.
Now the reason we want to keep the pairs straight is that the signal tends to stay on the pair because the wires are twisted around each other. As we learned when we moved from category 3 to category 5, more twist, better signal retention on the wire, less interference with the adjacent pairs. Now if we split the signal between pairs, it spreads the signal out in the wire and creates crosstalk on the other pairs, causing the signal to degrade. The specifics are probably beyond the scope of this discussion, however, the importance of pairing the correct pins can be the difference between a functioning circuit and one that is troublesome.
Again, pins 1 and 2 must share a twisted pair, and pins 3 and 6 must share a twisted pair.
Good Luck! It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com
Ethernet on UTP wiring uses two pairs. One 'pair' is the transmit, one is the receive. It is important that a twisted pair of wires is used on pins 1 and 2, and equally important that a twisted pair of wires is used on pins 3 and 6. Often I find cables made up just like a USOC plug, or just some non-standard color code. As long as you actually have a pair on each pin pair listed it really doesn't matter to the ethernet connectivity what the color of the jacket is. However, there is really no reason to wire a plug or jack any other way than an approved standard.
Now the reason we want to keep the pairs straight is that the signal tends to stay on the pair because the wires are twisted around each other. As we learned when we moved from category 3 to category 5, more twist, better signal retention on the wire, less interference with the adjacent pairs. Now if we split the signal between pairs, it spreads the signal out in the wire and creates crosstalk on the other pairs, causing the signal to degrade. The specifics are probably beyond the scope of this discussion, however, the importance of pairing the correct pins can be the difference between a functioning circuit and one that is troublesome.
Again, pins 1 and 2 must share a twisted pair, and pins 3 and 6 must share a twisted pair.
Good Luck! It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com
- Status
