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Remote digital modem loop
When the remote digital modem loop is connected, the composite-channel data
transmitted by the local MiniStat-Four is returned from the remote modem (after
passing through the communication link and the local modem) to the receive line
of the local MiniStat-Four. Any data transmitted from the remote MiniStat-Four is
lost during loop connection.
This loop tests the complete transmission path, including the local MiniStat-Four,
its composite channel connection cable, the communication link, and the local
and remote modems.
As long as the loop is connected, the SYNC indicator of the local MiniStat-Four
must light continuously. Failure to do so, after satisfactory performance in the
analog modem loop, usually indicates a problem in the communication channel
and/or in the remote modem.
NOTE
The MAIN indicator may or may not be on (depending on data activity)
during all tests.
6.3 Calling Black Box
If you determine that a MiniStat-Four is malfunctioning, do not attempt to alter or
repair the unit. It is not user-serviceable. Contact Black Box Technical Support at
724-746-5500. The problem might be solvable over the phone.
Before you do, make a record of the history of the problem. We will be able to
provide more efficient and accurate assistance if you have a complete description,
including:
• the nature and duration of the problem.
• when the problem occurs.
• the components involved in the problem.
• any particular application that, when used,
appears to create the problem or make it worse.
• the results of any tests you might already have performed.
CHAPTER 6: Troubleshooting
