Chapter 4. Troubleshooting and Diagnostics ASM-20 Installation and Operation Manual
4-4 Local Test - Analog Loopback 11/4/99 12:34
4.5 Modem Self Test
The modem self test verifies that ASM-20 is operating correctly.
To verify that ASM-20 is operating correctly:
1. Press the ANA (Analog Loopback) push button on the front panel. Both
the TEST and DCD LEDs should light up. If the DCD LED does not light
up, check that the CARRIER jumper is ON or that the RTS signal is ON
(high).
2. Press the PATT push button. Verify that:
• DCD LED is still lit up
• TEST LED is still lit up
• ERR LED lights up for a short period.
The ERR LED should then turn off. If it lights up or blinks, then ASM-20
is faulty and should be replaced. If the test executes correctly, restore all
the push buttons and jumpers to the required position.
4.6 Local Test - Analog Loopback
This test checks the performance of the local modem, the local data terminal
and the cables connecting them. Perform it separately at the local and
remote sites.
ANA
Pressed
LINE
ASM-20
XMTR
RCVR
DATA
TERMINAL
CLK
CLK
DATA
Figure 4-3 Local ASM-20 in Analog Loopback