[asterisk-bugs] [Asterisk 0015386]: [patch] Milliwatt() is off by -11dbm

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15386 
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Reported By:                rue_mohr
Assigned To:                russell
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Project:                    Asterisk
Issue ID:                   15386
Category:                   Applications/app_milliwatt
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
Asterisk Version:           1.6.1.1 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-06-23 20:15 CDT
Last Modified:              2009-06-24 13:11 CDT
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Summary:                    [patch] Milliwatt() is off by -11dbm
Description: 

Confirmed on asterisk 1.4.25.1 and 1.6.1.1 that the milliwatt is about
-11dbm 

Standard PC system, T100P T1 card, to Newbridge Mainstreet 3624
using dahdi-linux-complete-2.1.0.4+2.1.0.2
Debian kernel linux-2.6.28
measured with dbm meter from channelbank

its -11dbm at 1.000kHz, and at 1.004kHz

This can be confirmed because it worked perfectly on same hardware before
software upgrade ( kernel-2.6.15  asterisk-1.2.15  zaptel-1.2.13). 

suspect slinear<->ulaw conversion process, can't confirm.

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 (0106916) russell (administrator) - 2009-06-24 13:11
 https://issues.asterisk.org/view.php?id=15386#c106916 
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To clarify the intent of the patch, I realized after looking at this issue
that the change in behavior of the Milliwatt() application was likely the
cause of this issue.  By default, the tone generation code in Asterisk
(what Playtones() uses internally), puts a -8dB gain on the generated
signal (according to a comment in the code, anyway).  This is where the
loss was coming from that was observed in this bug.

So, I hacked up a quick patch to switch to using the ast_playtones_start()
API call directly, so that we could control the volume. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-06-24 13:11 russell        Note Added: 0106916                          
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