[asterisk-bugs] [Asterisk 0016017]: v23 caller id detection (UK) less than 100%

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16017 
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Reported By:                troublebot
Assigned To:                
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Project:                    Asterisk
Issue ID:                   16017
Category:                   Channels/chan_dahdi
Reproducibility:            sometimes
Severity:                   minor
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           1.4.26.2 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-10-05 06:48 CDT
Last Modified:              2009-10-07 09:20 CDT
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Summary:                    v23 caller id detection (UK) less than 100%
Description: 
Around 1 in 100 will fail with callerid.c: No start bit found in fsk data

After implementation of polarity detection in wcfxo.c I initially believed
there was an issue with my implementation or the hardware (X100P SE). I
setup enhanced logging and data capture and discovered that this was not
the case. There is a certain amount of noise present most of which could be
removed with a band pass filter, which I believe should help detection
rates. I do not believe the noise is inherent in the line, most of the
noise can be characterised as low frequency noise (mentioned in si3034 spec
as dc offset) and 4khz squeal. I have the raw data captured directly from
wcfxo if there is any interest in improving this. 
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 (0111984) lmadsen (administrator) - 2009-10-07 09:20
 https://issues.asterisk.org/view.php?id=16017#c111984 
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davidw: thanks for the feedback! 

Issue History 
Date Modified    Username       Field                    Change               
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2009-10-07 09:20 lmadsen        Note Added: 0111984                          
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