Section 6 Troubleshooting Guide TRACER 4108/4208 System Manual60 © 2003 ADTRAN, Inc. 612804208L1-1Bsuitable RF signal. Suitable RF power levels for low error rate communication will range from-30 dBm to -90 dBm (TRACER 4108) or -30 dBm to -85 dBm (TRACER 4208) measured at theN-type connector input on the TRACER 4108/4208 unit.10. Resolve any signal level issues before proceeding.11. Examine the RF LOW LED on the front panel of each TRACER 4108/4208. If this LED isilluminated, then the TRACER 4108/4208 is receiving a relatively weak signal; however, if the RFDOWN LED is not illuminated, then the received signal is being suitably processed by theTRACER 4108/4208 system. If you are receiving a weak signal (RF LOW is ON), please verifythat the weak signal is not being caused by a faulty cable, an insufficiently tightened cable, orsome other installation-related problem. Also, make sure an unreasonably large attenuation valuehas not been selected if you are using an attenuator on a workbench setup.Use the tables in Section 2, Microwave Path Engineering Basics, of this manual to select theproper free-space attenuation value (in dB) based on the estimated length of the microwave path.Remember to subtract both antenna gains (local and remote) from the attenuator setting.12. Initiate a line loopback on the local TRACER 4108/4208 unit and run a test pattern from theconnected T1 equipment. This will verify the connection between the T1 equipment and the localTRACER 4108/4208 unit.13. Command a link loopback on the remote TRACER 4108/4208 unit and run a test pattern from theconnected T1 equipment. This will verify the data path across the RF link.Installing/Configuring T1 Hardware1. If possible, attach any or all of the intended T1 hardware to the TRACER 4108/4208 units usingthe same workbench setup. This step offers the perfect opportunity to configure your T1 hardwarefor proper functioning with the TRACER hardware.2. To significantly reduce the probability of an unsuccessful field installation, resolve any remainingT1 equipment-to-TRACER 4108/4208 configuration issues before field installation. See pages 57and 58 for more information on resolving T1 interface alarm conditions.External pattern generators are required to test data path integrity. A T1 BERT tester issuggested.