IBM 5500-01E, Operational, Installation, And Maintenance Manual

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Dropped Connection
• Is the baud rate setting too high for the modem? Check the modem
specifications.
• The modem cable could be faulty.
• The signal ground of the Communication Line is connected to the 5500
Control Unit’s frame ground. Therefore, do not connect the signal ground
to the frame ground in the modem. A cable problem could be the cause.
Check the modem manufacturer’s recommendations for a modem cable.
• The phone lines could be noisy.
• The modem initialization strings could be incorrect.
• The modems at the 5500 Control Unit and host could be incompatible
with each other.
• The host may time-out after a period of inactivity (no data transfers). This
is often true when connected to an ISP unless special arrangements have
been made.
Slow Connection
The following factors could cause seemingly slow transfers with the host.
Check the following items:
• Baud rate settings at both the 5500 Control Unit and the host. The
modems may not indicate their connection speed
• Incorrect modem initialization strings
• Noisy phone lines causing many retries
• Bad cables causing retries
• The ISDN Modem is configured for multilink but the Host/ISP does not
support this connection
• Traffic on the WAN for other clients of the 5500 Control Unit
• Heavy host traffic slowing the flow to the WAN
Network Station Troubleshooting