Troubleshooting A Pots Connection - Comrex ACCESS MultiRack Product Manual

Rate Drop and Retrain controls are similar in function to those provided on POTS codecs. MultiRack will initially
connect at the best data rate supported by the telephone line, and will display this rate on the Connections Tab
page.
FIgure 67 connectIons tAb durIng An ActIVe pots cAll
Selecting Rate Drop will force the system to drop to the next lowest connect rate at any time. Audio transfer will be
interrupted momentarily while the units negotiate the new connect rate. Alternately, Retrain will force the system
to initiate the entire training sequence again (the "chat" sounds heard at the beginning of a call). Audio loss will
occur for a longer time (approx. 7 seconds) but the modems will completely re-equalize the connection and return
audio when finished.
Once MultiRack has dropped to a lower rate, either by Rate Drop or Retrain from either end, there is no way to
force it to connect at a higher rate. If a higher connection rate is desired with MultiRack, disconnect the call and dial
again.

troubleshootIng A pots connectIon

There are dozens of factors that can affect the success of a POTS codec call, some within the user's control and
some not. Here's a short list of rules to follow for POTS codec connections:
• Use the POTS codec on a direct telephone company line and avoid in-house phone systems. A line used
by a fax machine usually provides this directly to MultiRack. (Be sure to disconnect the fax machine before
connecting the codec!)
• Check to see that there are no extensions or modems on the line—or at least arrange that no one uses
these during a broadcast.
• If there is call-waiting on the line, disable it by entering "*70" in front of the number being dialed.
• If possible, try the POTS codec out at the remote site prior to an actual broadcast at about the same
time of day as planned use. This will assist in determining expected connection rates and possible line
problems.
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