[Asterisk-Users] TDM400P Revision question.

[Robert Webb]

> On Mon, 11 Apr 2005 10:54:30 -0400
>   "Robert Webb" <asterisk at ropeguru.com> wrote:
> > 
> > Good morning all..
> > 
> > I was following a discussion on this list about the TDM400P 
> revisions. 
> >It is my understanding that the current revision that one 
> should have 
> >is the Rev. H and not the E/F. I have not yet been able to 
> verify the 
> >rev stamped on the board, but zaptel is reporting that I 
> have the Rev. 
> >E/F. I just bought this card in January direct from Digium and was 
> >wondering if I got the wrong Rev.
> >somehow?? I have been having some intermittent problems but only 
> >thought it was my setup.
> > 



I did some more testing today. I called Digium on 4/12 and they
suggested some things to try, like different motherboard, switching pci
slots, etc.. I did everything they asked, except for the mother switch
as I do not have a different one to put in the system at this time.

So, after all that, my ringing issue still persists. Too some
measurements from bot the card and my POTS line in both the on-hook
state and ringing state. I uses a digital multi-meter to make the
measurements on both. Here are the results....

TDM400P

Before slot change:

On hook idle:

43.8 Volts DC
0    Volts AC

Ringing:

0    Volts DC
56.4 Volts AC

After slot change:

On hook idle:

48.7 Volts DC
0    Volts AC

Ringing:

0    Volts DC
65.5 Volts AC



On my POTS line:

On hook idle:

43.8 Volts DC
.013 Volts AC

Ringing:

50.5 Volts DC
93.9 Volts AC


Could it bee that from the phone company they retain the DC offset
voltage while applying a ring frequency and as it appears on the TDM it
shuts off the DC offset when ringing starts. Could this be the issue
with those of us in the U.S. having ringing issues with the TDM's??


Robert