[Asterisk-Users] Which is the best fax-modem for testing ?

[Rich Adamson]

>      > Which fax-modem would you pick if you had to test fax capabilities ?
>      >
>     The fax modem is not really the issue with asterisk. By far, the
>     majority of existing analog fax machines installed and being sold today
>     will function just fine with asterisk.
> 
> 
> Hi Rich,
> 
> I got problems connecting  a Brother 8360P  
> (http://www.brother.co.uk/g3.cfm/s_page/50670/s_level/17020/s_product/FAX8360PU1 
> <http://www.brother.co.uk/g3.cfm/s_page/50670/s_level/17020/s_product/FAX8360PU1>)
> to a Digium TDM400P card on a production system.
> 
> This fax is running OK when directly plugged to PSTN but cannot seem to 
> hangup when connected to Digium TDM400P card.

The TDM400P card is the problem, not the fax machine. The issues with 
the TDM card have been discussed many times over the last two years, and 
mostly relate to the transfer of data packets between the card and the 
motherboard/OS. Its my understanding (which could be less then accurate) 
the problem has to do with clocking that leads to missed frames, which 
has a serious impact on reproducing any analog modem signals.

> So I was telling myself : "what if I could buy the most inclusive 
> fax-modem, connect it to a PC, and run a bunch of test scripts to gather 
> useful information on both production and preparation systems ?".

Total waste of money as the problem isn't the fax modem as noted above.

> For example, it seems that Brother 8360P uses Super G3 mode.
> Is there a fax-modem offering such capability so that I could easily 
> check if I still cannot  hangup when I enable or disable Super G3 mode ?
> 
> Ideally, I would run a batch script with a fax-modem-equiped-PC to 
> gather compliance inputs against V34 and other fax standards.
> 
> Your advice underlining A200D PCM switching capability is very relevant, 
> anyway, as it shows a way to prove a fax issue can be solved changing or 
> configuring an analog TDM board.

The A200D approach only works if the fax machine is directly connected 
to an fxs module on the A200D, and the pstn line is directly connected 
to an fxo module on the exact same A200D card.

Rumor has it that Digium is working on new card(s) that may also support 
faxing, but nothing has been announced as yet to my knowledge.