[Arm-dev] VoIP FXS port?

[Robert Moskowitz]

On 08/26/2015 12:13 PM, R P Herrold wrote:
> On Wed, 26 Aug 2015, Robert Moskowitz wrote:
>
>> Does anyone know of an VoIP FXS port other than the one for Raspberry PI:
>>
>> http://www.raspberrypi.org/forums/viewtopic.php?f=45&t=86601&p=716025
> The pricing looks unfavorable, compared to outboard dedicate
> units.  I see this at Amazon with minimal searching -- FXS and
> FXO combo listed
>
> Grandstream HT-502 Dual Port FXS Gateway
> $37.50
>
> GrandStream HT503 1-FXS/1-FXO Port Analog Telephone
> $54.26
>
> Grandstream GS-HT702 Handytone 2-FXS Port Analog Telephone
> Adapter
> $34.31

I have worked with the Handytones, connecting a fax to the FXS and tried 
to get T.38 passthrough working to a PBX.  It fails in all sorts of 
interesting ways.  T.38 itself is a problem.  This is why you want the 
FXS in your gateway.  The 502 is really not a full pbx to handle the FXS 
connected fax to an efax function either.  Thus the desire for a real 
pbx with an FXS port.

If all you want is a analog phone to a pbx, these ATAs work.  But fax is 
a different kettle of fish.