On Fri, 2009-02-27 at 14:07 -0700, Brandon B. wrote: > As of yet, I am unwilling to change the LBO to 0 to where it probably > should be because the system is working and I'm not sure exactly what > the LBO does. I'm aware some changes were made to deal with low audio > levels.
LBO stands for Line Built Out... it's essentially a measurement of the distance between your demarcation point (d-marc/smart jack/NIU) and your Asterisk box. As you can see from a sample system.conf (from DAHDI) or zaptel.conf (from Zaptel), it's an integer value from the following table: 0: 0 db (CSU) / 0-133 feet (DSX-1) 1: 133-266 feet (DSX-1) 2: 266-399 feet (DSX-1) 3: 399-533 feet (DSX-1) 4: 533-655 feet (DSX-1) 5: -7.5db (CSU) 6: -15db (CSU) 7: -22.5db (CSU) As I understand it, the LBO is effectively an attenuation value, with a higher number meaning less attenuation. This way, you don't get too hot of a signal with a short cable, or two low of a signal on long cable. Just how far is your Asterisk box from the demarcation point? > Also, I am trying to cross connect with another Asterisk system with > the normal LBO setting (i.e. span=1,1,0,esf,b8zs) but as of yet the > systems aren't seeing each other at all. Could the side with the high > LBO be confusing the other side somehow? Shouldn't be... you did use a T1-crossover cable to cross-connect the two Asterisk boxes, right? I've got a little T1 cross-connect diagram at http://www.asteriskdocs.org/cables/ if you need a reference. -- Jared Smith Digium, Inc. | Training Manager _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
