[asterisk-users] how to set iaxmodem receiving speed

[Steve Underwood]

Hi,

On 05/16/2012 09:59 PM, Larry Moore wrote:
> Read the subject line more closely.
>
> Tested receiving too,
>
> I set the Send & Receive speed of the receiving analogue modem to that 
> below, the log file on the sending modem (iaxmodem) reported it 
> capable of 9600.
>
> May 16 21:32:04.28: [ 2335]: REMOTE best rate 9600 bit/s
> May 16 21:32:04.28: [ 2335]: REMOTE max A3 page width (303 mm)
> May 16 21:32:04.28: [ 2335]: REMOTE max unlimited page length
> May 16 21:32:04.28: [ 2335]: REMOTE best vres R16 x 15.4 line/mm
> May 16 21:32:04.28: [ 2335]: REMOTE format support: MH, MR, MMR
> May 16 21:32:04.28: [ 2335]: REMOTE supports T.30 Annex A, 256-byte ECM
> May 16 21:32:04.28: [ 2335]: REMOTE best 0 ms/scanline
> May 16 21:32:04.28: [ 2335]: USE 9600 bit/s
>
> Perhaps the issue is with Hylafax.
>
> Setting the Transmit & Receive strings to "!24,48,72,96" seems to 
> yield the most reliability in transmission
If you have an ATA in the path that is often the case. Many of them 
badly mess up a FAX signal. Without such a distortion machine V.17 
should be fine.
>
> Cheers,
>
> Larry.
>
> On 16/05/2012 7:23 PM, Larry Moore wrote:
>> I have iaxmodem version 1.2.0 installed on my system.
>>
>> I have set the following in the IAX configuration file, SIGHUP'd 
>> FaxGetty and submitted a single page outbound fax via Asterisk;
>>
>> Class1RMQueryCmd:       "!24,48,72"     # enable this to disable V.17 
>> receiving
>> Class1TMQueryCmd:       "!24,48,72"     # enable this to disable V.17 
>> sending
>>
>> The resulting output from my T.38 Gateway reports the following;
>>
>>     -- Connection Statistics
>>         Bit Rate :7200
>>         ECM : No
>>         Pages : 1
>>     -- Hungup 'IAX2/iaxmodem0-11055'
>>
>> I also tested with the maximum speed set to 4800, the image was 
>> received however the responses to EOP timed out, I don't know if the 
>> is to do with my Asterisk T.38 gateway or my VoIP providers T.38 
>> gateway. The result was the fax was retried for the defined number of 
>> attempts.
>>
>> Cheers,
>>
>> Larry.
>>
>> On 16/05/2012 6:28 PM, gincantalupo wrote:
>>> Hi all,
>>>
>>> I'm trying to lower my iaxmodem speed but still I haven't found any solution...I tried to add
>>> Class1RMQueryCmd:       "!24,48,72"
>>> to config.IAXtty but does not work...Hylafax says it it running at 9600 (sometimes at 14400) baud..
This is correct behaviour. The sending side has fine control over the 
modem modes it uses. The receiving side can only specify that V.27ter, 
or V.27ter+V.29 or V.27ter+V.29+V.17 are OK. So, if you allow the 
7200bps mode of V.29 you are compelled to allows the 9600bps mode too.

Steve