RAD Data comm ASM-20 operation manual Modem Self Test, Local Test Analog Loopback

Chapter 4. Troubleshooting and Diagnostics ASM-20Installation and Operation Manual

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.

A N A

P re sse d

D ATA

TE R M IN A L

C L K

C L K D ATA

X M TR

R C V R

L IN E

A S M -2 0

Figure 4-3 Local ASM-20 in Analog Loopback

4-4 Local Test - Analog Loopback