Using Cat5 for voice and Data

marcplante

Senior member
Mar 17, 2005
687
9
91
I have a line coming into the home office that is used 98% of the time for Data and 5% of the time for the OCCASIONAL fax. Can I use the idle pair in the middle of the Cat5 cable to terminate a voice port for occasional use.

Otherwise I may go to straight data and skip voice functionality.

Thanks,
 

oppie1

Senior member
Jan 16, 2001
578
2
81
Oh my god... That's the most ghetto'ish way to rig something like that. You should be ashamed to post that link and say it seems ok to do ;)
 

marcplante

Senior member
Mar 17, 2005
687
9
91
if i were using the phone line actively more than 2x/yr for the occasional fax, I'd try another solution, but given the fact that I virtually don't use the line, I figure it's an acceptable hack (yes, I know it's a hack) and compromise.
 

ScottMac

Moderator<br>Networking<br>Elite member
Mar 19, 2001
5,471
2
0
It's not a good thing to do because a) it's out of spec (as if anyone cares about specifications anymore) and b) the 100VAC, 20Hz ring voltage on the phone line can cause a crosstalk effect ranging from interference with the data to smoking your NIC, depending on the quality of the NIC (maybe the switch port, depending on the surge protection capability, and c) breaking out the pair will cause full-time degradation of the data pair (see "out of spec" - yu no longer have a category-anything system, it rates with plain phone wire).

People do it and seem to get away with it, success and performance vary widely with the quality of the overall system.
 

Red Squirrel

No Lifer
May 24, 2003
71,312
14,085
126
www.anyf.ca
Ethernet actually uses all pairs I believe, unless you're only running 100 or less. Either way I would not do this, just bite the bullet and run another cable.

When I run a drop I usually run 4 cables at a time. I usually do 1 voice and 3 data, they all terminate at the patch panel with proper connectors and even if I'm not using them at least I can patch them in as needed.
 

gsaldivar

Diamond Member
Apr 30, 2001
8,691
1
81
I would do VoIP and eFax, leave the Cat5 intact, and avoid any interference and speed issues...
 

marcplante

Senior member
Mar 17, 2005
687
9
91
I skipped the phone line and went straight data. I just attach PDFs to emails instead of faxes anyhow. It's nice to see the full 25 Mbps from the router instead of the 6-8 I got from the power line adapter. Good to hear the detailed reason not to split the line. Thanks for the input.
 

gsaldivar

Diamond Member
Apr 30, 2001
8,691
1
81
Consider creating an account at Greenfax.com. They charge nothing per month to keep the account open. If you need to send a fax, just send to number@greenfax.com (example: 13105551212@greenfax.com) and attach anything you want: PDF, Word, Excel. They convert all the attachments, send the fax, and email you confirmation in minutes. The only thing you pay is a few cents per minute depending on how long it takes to send each fax. You deposit increments of $25, and it's deducted from that balance. I've used this service for many years and find it to be excellent.

Good luck.