web statisticsweb stats Business Phone Systems Tech Talk Forum - VOIP & Cloud Phone Help

Business Phone Systems

Previous Thread
Next Thread
Print Thread
Rate Thread
#4149 12/07/04 06:07 AM
Joined: Nov 2004
Posts: 2
xland Offline OP
Member
OP Offline
Member
Joined: Nov 2004
Posts: 2
ISDN compatibility problem

Background info:
Our company has been using a popular fax server software with pots lines for a few years. The fax server is setup with a (8) line Equinox v.90 multimodum and (2) 3Com Soprtster modems (10) lines total. We recently moved the office and upgraded our communications infrastructure with the "local phone conglomerate’s” ISDN for voice. We now have line cards from the NEC Elite Plus PBX converting the digital signal to analog for the fax servers modems via a distribution block. The problem is we can ONLY receive complete fax transmissions when the receive rate on the fax server software is set to 2400. Any higher we get half, quarter or incomplete faxes. When we setup a POTS line to test we can receive at 14400 without a single problem. Also, when we setup a standard fax machine through the PBX it will work fine. Voice is not an issues. What we have done is made sure we have the latest version of the software on the fax server and modems. My computer vendor is saying the problem is from the PBX . The phone vendor checked environmental issues like lights on the PBX power circuit and the like. We took the db levels on the PBX up and down and checked the PBX settings with the Telco. We also put line attenuators on the cable 2db-8db. My phone vendor is saying it’s a problem with the modems. Telco said test was fine, no problem. Can anyone help shed some light on this? Thanks in advance for any help.
Xland

Atcom VoIP Phones
VoIP Demo

Best VoIP Phones Canada


Visit Atcom to get started with your new business VoIP phone system ASAP
Turn up is quick, painless, and can often be done same day.
Let us show you how to do VoIP right, resulting in crystal clear call quality and easy-to-use features that make everyone happy!
Proudly serving Canada from coast to coast.

#4150 12/07/04 09:09 AM
Joined: Sep 2004
Posts: 4,194
Likes: 2
Member
*****
Offline
Member
*****
Joined: Sep 2004
Posts: 4,194
Likes: 2
Have you checked with your vendor? I would hazarrd a guese your phone system can't handle high speed connects on analog ports. This is where you seperate the men from the boys in PBX land BTW.

#4151 12/07/04 01:37 PM
Joined: Nov 2003
Posts: 1,313
Member
Offline
Member
Joined: Nov 2003
Posts: 1,313
i'm thinking that the analog ports on a nec system will only do 2400 or 9600 baud thru the system

#4152 12/07/04 06:48 PM
Joined: Jun 2003
Posts: 3,273
Likes: 1
Moderator-Toshiba
*****
Offline
Moderator-Toshiba
*****
Joined: Jun 2003
Posts: 3,273
Likes: 1
I've come across a similar problem which turned out that the pbx (not an NEC) did not have 3.1 khz audio bearer services on for the b channels. The b channels were set for speech. Not sure if this applies to you, but it doesn't hurt to check it.

#4153 12/08/04 02:34 AM
Joined: Sep 2004
Posts: 4,194
Likes: 2
Member
*****
Offline
Member
*****
Joined: Sep 2004
Posts: 4,194
Likes: 2
I would would test calling out on a modem as well to see if you can get 56k modem speeds through the PBX. Theorhetically if the analog port isn't doing something funky you should be able to get 56k speeds thourgh the PRI as you are going analog->digital.

#4154 12/22/04 02:29 PM
Joined: Nov 2004
Posts: 2
xland Offline OP
Member
OP Offline
Member
Joined: Nov 2004
Posts: 2
Fixed it.....It turns out our clock generator settings were wrong. We hade it looking for the T1 card in the wrong slot. Telco tech said it sounds like a clocking problem. We tried it with no clock and every fax was bad & voice was good. So we looked hard at the clock settings.
Thanks for the help.

#4155 01/05/05 02:07 PM
Joined: Aug 2004
Posts: 44
Member
Offline
Member
Joined: Aug 2004
Posts: 44
Quote
<font face="Verdana, Arial" size="2">Originally posted by xland:
Fixed it.....It turns out our clock generator settings were wrong. We hade it looking for the T1 card in the wrong slot. Telco tech said it sounds like a clocking problem. We tried it with no clock and every fax was bad & voice was good. So we looked hard at the clock settings.
Thanks for the help.
</font>


Indeed. I identified this issue earlier in 2004 and was hoping NEC would post a TIM bulletin on it. Invalid clock slip timings can affect modem/fax connectivity on the Key Systems and also plague the bigger 2000/2400 switches. If you *EVER* have modem/fax issues at a job site, always ensure the clock slip timings are configured to the PRI/T1 properly.

------------------
NEC Unified Solutions / Voice Mail and Unified Messaging | Active Voice, LLC

[Linked Image from necunified.com] [Linked Image from activevoice.com]


Moderated by  MooreTel 

Link Copied to Clipboard
Forum Statistics
Forums84
Topics94,262
Posts638,697
Members49,757
Most Online5,661
May 23rd, 2018
Popular Topics(Views)
211,100 Shoretel
187,712 CTX100 install
186,800 1a2 system
Newest Members
BPopilek, Rich F, LewisR, TDKs79, Buttinset
49,757 Registered Users
Top Posters(30 Days)
dexman 18
Toner 11
TDKs79 8
teleco 4
Who's Online Now
0 members (), 140 guests, and 24 robots.
Key: Admin, Global Mod, Mod
Contact Us | Sponsored by Atcom: One of the best VoIP Phone Canada Suppliers for your business telephone system!| Terms of Service

Sundance Communications is not affiliated with any of the above manufacturers. Sundance Phone System Forums - VOIP & Cloud Phone Help
©Copyright Sundance Communications 1998-2024
Powered by UBB.threads™ PHP Forum Software 7.7.5