On Thursday 23 March 2006 17:34, Reza - Asterisk Enthusiast wrote: > Hello Frank... granted no timing on POTS lines, but what about the FXO > devices/cards itself? Everyone without an exception who I personally know > running VOIP business - has an x100p/x101p or clone, or a TDM400P or a > basic Sangoma A200 - even though not a single RJ-11 PSTN line is going into > the cards.
The cheap-ass FXO devices have the requisite 1000Hz timer source on them. Granted it's not as stable or accurate as the atomic clocks the telcos use, but for what we're doing it's close enough. The reason they're putting those cards in is to get that timing source for MeetMe/MOH. 1000.0102330Hz is far better than 1024.00Hz. You may still slip but chances are that the conversations are short enough that enough time just won't build up, and when it does slip it won't slip again for quite some time. > So does this mean the x100p/x101p/x100clones are irrelevant as a timing > device for MeetMe & MoH functions? If this is irrelevant, how is the > timing/synchronizing being done on my boxes where ztdummy was never > compiled? The cheap FXO cards *are* the zaptel timing device. Ztdummy is an alternate, poorer zaptel timing device. Did you get MeetMe/MOH on your boxes before installing ztdummy? Remember for pure VOIP installations, (no MeetMe/MOH) Asterisk is taking timing from the incoming packet stream(s). > Am I missing something critical and obviously silly, or am I opening a new > can of worms? :). The can is open, and the worms are everywhere. Don't worry about it. :-) -A.
