[asterisk-users] Fax from FXS to PRI

[Jeff LaCoursiere]

On Tue, 2011-09-20 at 20:57 -0500, Don Kelly wrote:
> On Tue, Sep 20, 2011 at 4:43 PM, Adam Moffett
> <adamlists at plexicomm.net> wrote:
> 
> If I have a 4 port Digium FXS card and a single port PRI card on the
> same asterisk box, is it expected that I'd be able to plug a fax
> machine into the analog FXS port and have no problems sending or
> receiving faxes?  Our connection to the Telco is on the PRI obviously.
> 
> <snip>
> 
> 
> Nobody can say for sure.  It is not a supported configuration.  I can
> tell you that I have had great success and wasted days messing around
> with this configuration.  
> 
> <snip>
> 
>  
> 
> Again, it has never been a supported configuration by Digium, and
> everyone that has dealt with faxing in Asterisk especially on
> different systems will tell you that you won't know until you try.
>  And even then, is it worth days of your time trying to get it as
> close to a POTS line as possible?
> 
> <snip>
> 
> 
> Thanks,
> Steve T
> 
> This is a scary answer—you’re saying that what should be simple “TDM”
> FXS to PRI does not work?
> 
>  
> 
> Are you suggesting this is an Asterisk problem or a Digium hardware
> problem?
> 

Like most faxing issues, at it's root it is a timing problem IMO.
Sangoma makes a special timing cable to link their cards so you can do
exactly what you are asking to do.  I've never purchased it, but last I
looked into the issue, that is what they suggested.

j