DataComm V.34 PL, Operation Manual

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Tests Analog Loopback (ANALOOP)
4-2 DataComm V.34 PL Modem 060R115-000
Installation and Operation Issue 1
Analog Loopback (ANALOOP)
The Analog Loopback (AL) test mode, illustrated below, is provided to isolate problems in the
modem operation and the DTE interface. Specifically, AL tests modem modulator/demodulator
operation, DTE receive/transmit operation, and DTE interface operation.
Table 4-1 Analog Loopback
Step Front Panel
1. To start the test, press AL.
2. The modem flashes the TM LED and displays
the test name (LL) while it is setting up the
test, then lights the TM LED and decimal
point three while the test is running.
3. Enter test data at the DTE. Compare the data
that was entered at the DTE with the data that
is looped back and displayed by the DTE. If
errors occur frequently, a problem may exist
in the modem, the DTE, or the DTE-to-
modem connection. Refer to
Figure 4-1 , Fault
Isolation Sequence.
4. To end the test, press AL, RDL or DL.
Modem transmitter
Modem receiver
Send data
Received data
DTE
Communications line
Local loopback
V.34 PL
TR SD RD MR RS CS CO GD TM ALM OH
AL ST RDL DL SEL RST
ADV
1. To start the test, press AL.
2. TM flashes and the test name (LL) appears on the LCD while it is setting up the test, then TM lights
and decimal point three appears while the test is running.
3. Enter test data on DTE. Compare this data with the data
that was looped back and displayed on the DTE.
4. To end the test, press AL.