[asterisk-bugs] [DAHDI-linux 0013562]: [patch] It's necessary to have low frequency filter for tx signal of DAHDI.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=13562 
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Reported By:                biohumanoid
Assigned To:                sruffell
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Project:                    DAHDI-linux
Issue ID:                   13562
Category:                   dahdi (the module)
Reproducibility:            have not tried
Severity:                   feature
Priority:                   normal
Status:                     confirmed
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Date Submitted:             2008-09-26 04:27 CDT
Last Modified:              2009-06-02 05:22 CDT
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Summary:                    [patch] It's necessary to have low frequency filter
for tx signal of DAHDI.
Description: 
It's necessary to have low frequency filter for tx signal of DAHDI. 
Otherwise, low-frequency signal from IP can reach a leased line, and
return back with nonlinear distortions. This will break an echo canceller.

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 (0105877) biohumanoid (reporter) - 2009-06-02 05:22
 https://issues.asterisk.org/view.php?id=13562#c105877 
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dahdi-base.c.https://issues.asterisk.org/view.php?id=2.patch
Changed the condition
(ECHO_MODE_IDLE != chan->ec_state->status.mode)
to
(ECHO_MODE_ACTIVE == chan->ec_state->status.mode)
I think we have no reason to call HPF in FAX mode.
echocanceller can read status.mode and ignore the request, but what for ? 

Issue History 
Date Modified    Username       Field                    Change               
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2009-06-02 05:22 biohumanoid    Note Added: 0105877                          
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