Black Box 3600 MODEM manual Modem and Telephone Line Check, Part

Hardware Options

Modem and Telephone Line Check

Part I

1)Configure the modem for LOCAL ANALOG LOOP WITH TEST PATTERN. This terminates the local modem telephone lines into 600 ohms and connects the local modem transmit output amplifier back to its own receiver through the AGC. Transmit input data from the terminal is inhibited and is substituted with a V.52 test pattern.

2)This test checks operation of the local modem modulator and demodulator circuitry and should be attempted at both local and remote sites if operators are available.

3)When random errors are present, the TEST PATTERN ERRORS display counts receive errors.

4)If the circuitry is working properly, the front panel indicators show the following:

5)Configure the modem for LOCAL ANALOG LOOP to switch the transmitter back to its normal data input.

6)If the transmit data input is in a mark hold condition, both the TD and RD indicators should remain off.

7)If the transmit data input is in a space hold condition, both the TD and RD indicators should come on. All other indicators should remain the same.

8)If the indicators are correct, the modem is probably operating correctly.

9)If the preceding tests were not successful, call Technical Services. Refer to the “Calling Technical Support” section on page 12-2.

D-2 Modem 3600