Motorola V.3600 manual Testing the Local Modem, Local Analog Loopback &T1

Test Mode Operation

Testing the Local Modem

Test local operation with the modem offline in command mode. Use LAL and LAL/TP to test the local modem and the communications to the local DTE.

Note

Figures 7-1 through 7-5 include LED test indications. These indications are valid when DTE options are set by factory option set #1 and RTS is active from the DTE. Where indicated, RD and/or TD may be on, off, or flashing depending on the type of DTE and its operating state.

Local Analog Loopback — &T1

In Local Analog Loopback the modem transmitter connects to its receiver so the analog signal normally sent over the telephone line is received locally.

If operating on leased lines, the lines are terminated into 600 ohms (Figure 7-1). If off hook on a dial-up line, the modem is forced on hook.

Figure 7-1. Local Analog Loopback

(4-Wire Operation and 2-Wire Operation)

For 2-wire operation, Analog Bilateral Loopback is invalid. In 4-wire operation, Analog Bilateral Loopback connects the receive line to the transmit line through a buffer amplifier.

Test the local DTE and cable by entering the &T1 command. Enter a test message and verify it is echoed on the screen. If it is not returned exactly as entered, the terminal equipment or data cable is at fault.

V.3600 7-3