Vector-LP Radio Beacon Transmitter Technical Instruction Manual Page 5-7Section 5 Maintenance and Troubleshooting Issue 1.1Table 5-1: Troubleshooting and Replacement Tips (Continued)Front PanelLEDStatusMessage Action See Troubleshooting/Replacement ParagraphSee Re-calibrationParagraphOutput Network SWR Shutback RF power has been inhibited due to high reflected power. Check the RF path between the transmitter’s RFoutput and the antenna system. If the instantaneous reflected power exceeds 80 W, the RF output is shutback. The power level will automatically recover to its previous level. If two consecutive SWR shutbacksoccur within a two second period, the RF output is cut back (see SWR Cutback).N/A N/AOutput Network Cutback Level1-18There are 18 steps (or cutback levels) available. The transmitter will continue decreasing or increasing theRF output power until normal operating power is achieved, at which point the SWR alarm will disappear.If two consecutive SWR shutbacks occur within a two second period, the transmitter enters the next highestcutback level (1-18).If the average peak reflected power exceeds 30 W (VR250) or 15 W (VR125), the transmitter enters the nexthighest cutback level (1-18). When the reflected power level falls below 30 W (VR250) or 15 W (VR125), thetransmitter will enter the next lowest cutback level (1-18).During a cutback, the System Diagram’s Output Network alarm lamp blinks and the Diagnostic Displayindicates the cutback level (1-18).N/A N/AChangeover Monitor Changeover Check the accompanying error message to determine the cause of the changeover. N/A N/AChangeover Monitor Shutdown Check the accompanying error message to determine the cause of the shutdown. N/A N/AExternal Alarm Ext Interlock Open An external interlock circuit is open. Check the integrity of the circuitry connected between terminals TB1-19and TB1-20 of the remote interface PWB (A3).N/A N/AExternal Alarm Charger Alarm Check for battery charger failure. N/A N/AExternal Alarm Low Battery Voltage The battery voltage is below the low voltage threshold. Check battery. N/A N/AExternal Alarm ATU Not Responding The associated ATU is not responding. Check connection between transmitter and ATU. N/A N/AExternal Alarm RCMI Not Responding The NDB site interface PWB is not responding. Replace the NDB site interface PWB. N/A 4.3.5.14.3.5.3
