Gigabit QAM Modulator Model D9479 Hardware Installation and ...

Chapter 5 Troubleshooting the GQAMLCDDescriptionRF (1-4) DCLock detecterrorSee also RF (1-4) UC Lockdetect errorRF (1-4) DCPLL unlockedRF (1-4)EEPROMfailureRF (1-4)Exceeded maxtempRF (1-4) levelnot calibratedAlarmLevelProbable CauseMajor • Downconverter (DC) lockdetect signal not functioningcorrectly. During ModulatorMCU Power On Self Test(POST), the lock detect signalfrom the downconverter phaselockedloop (PLL) did notindicate an unlocked conditionwhen one existedNote: Since the MCU cannotcorrectly detect locked orunlocked status, the RF Outputfield displays “MUTED” whenthis condition occurred• The output convertersynthesizer lock detect circuitryhas malfunctionedMajor Downconverter (DC) PLLsynthesizer cannot lock. The outputfrequency may not be correct. TheRF Output field displays “MUTED”when this condition existsMinor Modulator EEPROM failure. TheEEPROM on the modulator board isnot present or is not operational. Ifthis alarm is set, RF calibration datais not available and the “RF (1-4)Level not calibrated” alarm is alsoactiveMinor The internal temperature of theGQAM is more than 70ºC (158ºF)Minor One of the RF Level settings is notcalibrated to the correct frequencyor the EEPROM that stores thecalibration data is not operationalCheck and CorrectContact Cisco ServicesContact Cisco ServicesContact Cisco Services• Remove vent obstructions• Provide more cooling andventilation• Check the exhaust fans• Contact Cisco ServicesImportant: You shouldcheck the temperature onthe GQAM daily or morefrequently if possible.Contact Cisco Services100 78-745431-01 Rev E