User's Manual

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Modem 34336
7.8 Remote Modem Diagnostics
The Modem performs two tests on compatible remote modems: remote
digital loopback (RDL) and remote digital loopback self test (RDLST).
If a problem is encountered and the local Modem passes all diagnostic tests,
the local Modem can test the remote modem.
Two (noncontiguous) REMOTE TEST screens are on the Modem’s LCD.
The remote tests are initiated from the REMOTE TEST menu. (Select RMT
from MAIN MENU screen 2. Select TEST. Then, select the test type.) A
remote test cannot be initiated unless the Remote Test option is enabled
on the remote modem. This option (also REMOTE TEST on the LCD) is
accessed via SETUP screen 4.
7.8.1 R EMOTE D IGITAL L OOPBACK (RDL) T EST
The RDL test (Figure 7-6) allows testing of the local modem, remote modem
and telephone line from the local site.
In Hayes mode only, initiate the RDL test using the command &T6 (preceded
by AT). In any mode, initiate the RDL test from the Modem’s front panel.
Both modems should be on-line and should be tested at the DTE’s data rate.
Ensure that the DTR circuit is on. If TR is present on the EIA status screen,
the DTR circuit is on.
Figure 7-6. Remote Digital Loopback Test (RDL).
DATA TERMINAL EQUIPMENT
(DTE) AT LOCAL SITE
LOCAL
MODEM
RECEIVER
REMOTE MODEM
TRANSMITTER
RECEIVER
TRANSMITTER