IBM 3746-900, Installation And Maintenance Manual

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Press the
↑
key until the C108 (DTR) message is displayed on the top
row.
Press the
→
key until the Forced On message is displayed on the
bottom row.
Press Enter twice to select the option and to return to the modem
operational mode message.
Step 9. Dial the modem phone number from another telephone. You should hear
the ringing tones and then the 2100-Hz answer tone from the called
modem in the handset of the dialing telephone. If you hear the answer
tone, go to
step 11 . Otherwise, continue with step 10 .
Step 10. If you do not hear the modem answer tone, verify that the telephone line
is operating properly. In most countries, you can do this by replacing the
modem with a handset and then attempting a second time to dial the
modem phone number from another telephone to verify that the handset
rings properly.
Connect again the modem to the public switched network and try dialing
the modem phone number again. Observe the front panel OH light. This
light turns
off when the modem answers. If this attempt to call the
modem fails, the modem is defective. Replace it.
Step 11. Set the modem power switch to OFF.
Note: The following steps assume that your DTE is already installed and
operational.
Step 12. Connect the 25-pin V.24 cable from the DTE to the 25-pin connector on
the modem rear panel. Fasten the connector retaining screws.
Step 13. Set the modem power switch to ON. Wait until the modem operational
message is displayed on the operator panel (about 30 seconds).
Step 14. Now the modem is ready for operation; you can try it with your system. If
you observe a basic system problem, such as the DTE not being able to
send commands to the modem successfully, verify again that your
individual modem configuration parameters are matching your system
requirements. If you have a problem while using the modem, refer to
7857 Guide to Operation , GA13-1839, chapter "Problem Determination."
If the 7857 operator panel does not show the following message (see Figure 1-26),
the modem needs to be configured through the operator panel, go to “Setting the
7857 Connected to the COM1 Connector (ASYN)” on page 1-31.
┌────────────────────┐
│IBM 7857 V25BIS
aa │
│td_ rd_ dsr ec_ ll_│
└────────────────────┘
with: OH LED OFF
DTR(108) LED ON
CTS(106) LED OFF
CD(109) LED OFF
Figure 1-26. 7857 Operator Panel Display
1-30
3745-XXA 1-30 3746-9X0: 6578 SPIM