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<DIV><SPAN class=893351520-25042005><FONT size=2>If you are running a Cisco VoIP
gateway you can send a 0dBm 1000Khz test tone into or out of a voice port
with:</FONT></SPAN></DIV>
<DIV><SPAN class=893351520-25042005><FONT size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=893351520-25042005><FONT size=2>"test voice
port <port#> inject-tone network 1000hz"</FONT></SPAN></DIV>
<DIV><SPAN class=893351520-25042005><FONT size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=893351520-25042005><FONT size=2>to measure the tone do
a:</FONT></SPAN></DIV>
<DIV><SPAN class=893351520-25042005><FONT size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=893351520-25042005><FONT size=2>"sh call active voice
brief"</FONT></SPAN></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><SPAN class=893351520-25042005>>></SPAN>Another common problem that
causes echo in networks is not setting your<BR><SPAN
class=893351520-25042005>>></SPAN>loss plan correctly.
You need to be sure that you aren't coming in too<BR><SPAN
class=893351520-25042005>>></SPAN>hot at any of your analog
interfaces. In general you should see a signal<BR><SPAN
class=893351520-25042005>>></SPAN>between -20dbm and -12dbm when someone
is talking on the line. If it is<BR><SPAN
class=893351520-25042005>>></SPAN>significantly hotter then you run the
chance of having a larger reflected<BR><SPAN
class=893351520-25042005>>></SPAN>signal resulting in echo. I
typically try padding down analog levels by<BR><SPAN
class=893351520-25042005>>></SPAN>3dB at a time to see if echo is
reduced. <BR><SPAN class=893351520-25042005>></SPAN>How do
you measure the amplitude of a pstn line? As an audio engineer in a<BR><SPAN
class=893351520-25042005>></SPAN>previous life, I would love to be able to
send standard level tones down a<BR><SPAN
class=893351520-25042005>></SPAN>pstn line and measure the amplitude at my
end, then adjust the input gain<BR><SPAN
class=893351520-25042005>></SPAN>accurately. Is there a way to do
this?<BR><BR></DIV></BODY></HTML>