I agree Adtran is the way to go, especially when handing-off to legacy phone systems with a PRI.
Erich Kaiser North Central Tower Consulting [email protected] Office: 630-621-4804 Cell: 630-777-9291 On Wed, Feb 18, 2015 at 6:09 AM, Adam Moffett <[email protected]> wrote: > Adtran Total Access has been my happiest multi line ATA experience. Not > cheap though....and not simple as the Grandstream. In fact the config is > obtuse in some ways. Greatest chance that everything works though. > > Most lines are loop start. I have never seen an ATA that could do ground >> start. >> Ground start was used by some PBX systems. The PBX would put a ground on >> the tip side of the line telling the central office to send dial tone. >> >> If it works at all, it is working. You may have some RIP silence timer >> type of problems. >> And, if the line voltage is low, some things can get unhappy. Check the >> ATA voltage on the pair when it is not off hook. >> >> Some PBX type of equipment and older fax machines wanted to see -48 volts >> nominal on the open line. >> And, interrupting loop current is a way for a central office to force a >> disconnect. If your voltage is too low, the PBX may think you are sending >> a disconnect. And the ATA is probably not interrupting loop current when >> the line disconnects from the far end. >> >> You may be sending data. Caller ID comes in a burst of Bell 202 FSK >> modulation. It sounds like data to a telco guy and in fact it is data. >> >> You may want to upgrade your SIP equipment. I am sure somebody like >> Adtran or perhaps Tellabs has a carrier class ATA. This one says it has >> -48 Volts on the loop: >> >> http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cata/187/1_0/english/ >> administration/guide/sip/187adm80/a187_agCspc.html >> >> -----Original Message----- From: Nate Burke >> Sent: Tuesday, February 17, 2015 4:24 PM >> To: Animal Farm >> Subject: [AFMUG] OT: Types of Telephone lines >> >> I'm trying to hook an ATA (Grandstream GXW4004) up to a Mitel PBX. The >> Mitel is expecting a 'Loop Start' line. I've read through the Wikipedia >> pages, and looked through the documentation. But I'm still confused. >> How do you tell if an ATA is producing lines that are 'Loop Start' or >> 'Ground Start' Or is there something else it's doing. >> >> The client is having issues where some calls are terminating in the >> middle of a conversation, or not disconnecting and leaving the line >> open. The PBX Contractor (the only way you can do anything with a Mitel >> PBX is through a Contractor) is telling them that they can make no >> adjustments to the analog card in the Mitel, and it's not working >> because our lines are 'Not up to industry standards for loop start >> lines.' When they had ILEC POTS lines, the PBX was working normally, >> this just happened when we switched them to an ATA. >> >> I have a ticket open with Grandstream, but I thought I'd ask here. Is >> there a way to test loop vs Ground start, and verify that the ATA is up >> to 'Industry standards'? The Contractor is Telling the client that our >> lines have low voltage, and there is "data" present on the line. I >> wasn't on site when the tech was, so I have no idea what sort of testing >> he was doing. >> >> Any telephone guys care to offer insight? >> >> Thanks, >> Nate >> > >
