HP TM 11-6625-2779-14&P manual Front Panel Trouble Analysis, Dial BAT

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Section V				Model 3555B
	Table 5-6. Front Panel Trouble Analysis

		3555B SHOULD INDICATE	SET ACTUALLY	CORRECTIVE
INPUT CONDITIONS	FUNCTION	(RANGE + METER)*	INDICATES	ACTION
FUNCTION: VF/Nm	DIAL BAT	In green area, BAT GOOD		Replace battery
1kHz, 0dBm, 600 BAL	Input: TMS, TERM
	VF/Nm: 600 BAL	0dBm ±0.2dBm		Refer to Paragraph 5-34
	Change INPUT to BRDG
	RANGE to +10dBm	+6dBm ±0.2dBm		Refer to Paragraph 5-34
	Depress 900 BAL	+4.2dBm ±0.2dBm		Refer to Paragraph 5-34
	INPUT to TERM
	RANGE to 0dBm	-0.1 5dBm ±0.2dBm		Refer to Paragraph 5-34
FILTERS	INPUT: NOISE TERM	0dBm		Refer to Paragraph 5-37
	NOISE WTG: 3kHz FLAT
	VF/Nm, 600 BAL	0dBm ±0.2dBm		Refer to Paragraph 5-37
	Change to C MSG	0dBm +±0.2dBm		Refer to Paragraph 5-37
	Change to 15kHz FLAT	0dBrn ±0.2dBm		Refer to Paragraph 5-37
	Change to PROG	0dBm ±1dBm		Refer to Paragraph 5-37
FUNCTION: CARRIER
20kHz, 0dBm	INPUT: TMS, TERM
600 BAL	FUNCTION: CARRIER	0dBm		Refer to Paragraph 5-34
	600 BAL
	Change INPUT to BRDG
	RANGE to +10dBm	+6dBm ±0.5dBm		Refer to Paragraph 5-34
	Depress 135 BAL
	RANGE to +20dBm	+12.6dBm ±0.5dBm		Refer to Paragraph 5-34
	Change INPUT to TERM
	RANGE to 0dBm	-2.2dBm ±0.5dBm		Refer to Paragraph 5-34
Change to 75	UNBAL INPUT: TMS, TERM
	FUNCTION: 75 UNBAL	0dBm ±0.2dBm		Refer to Paragraph 5-34
	RANGE: 0dBm
	Change INPUT to BRDG
	RANGE to 10dBm	±6dBm +0.2dBm		Refer to Table 5-8
	Change INPUT back to
	TERM
	RANGE to 0dBm	0dBm ±0.2dBm		Refer to Table 5-8
RANGE
1kHz, 600 BAL,
LEVEL +10dBm	Change RANGE to +10dBm
	FUNCTION: VF/Nm 600 BAL	+10dBm ±0.2dBm		See Paragraph 5-35
LEVEL -10dBm	Change RANGE to -10dBm	-10dBm ±0.2dBm		See Paragraph 5-35
LEVEL -20dBm	Change RANGE to -20dBm	-20dBm ±0.2dBm		See Paragraph 5-35

5-12

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Contents HEADQUARTERS, Department of the Army Technical Manual Headquarters Department of the Army Reporting Errors and Recommending ImprovementsTM 11-6625-2779-14&P NSNReplaceable Parts List of Tables List of IllustrationsIii Section Introduction Maintenance Forms, Records, and ReportsScope Destruction of Army Electronics Materiel Administrative StorageReporting Equipment Improvement Recommendations EIR Items Comprising an Operable Equipment Specifications Voice Frequency Level Measurements 20Hz to 20kHzSection Section General Information IntroductionInstrument Identification Accessory Equipment SuppliedAccessory Equipment Supplied BAL ModificationPower Requirements Section Installation InspectionWarranty Exception BatteryInstallation and Removal of Battery Cover RemovalSection Controls Connectors IndicatorsBattery Operating InstructionsFront Panel Controls, Indicators, and Connectors Front, Side and Rear Pane Side Panel Controls and Connectors Level and Noise Measurements Level MeasurementsPage Noise Measurement Recorder Compatibility ApplicationsRecorder Compatibility Chart Crosstalk Measurements Identifying Noise CharacteristicsTransmission Loss Measurements Crosstalk Correction FactorMeasurements in DBC Input jacks are connected in parallel. If a 600 ohm Reinstall the set in its case0dBm 135 BALStep Procedure Level Measurement Noise Metallic MeasurementsExample Noise-to-Ground Measurements Balance MeasurementRecorder Calibration Transmission Loss MeasurementBlock Diagram Description Section Theory of Operation IntroductionDetailed Circuit Description Simplified Dial BAT FunctionInput Amplifier A3. Schematic No Range Attenuator A2Range Attenuator Setting AttenuationFILTERS. Schematic No Pads UsedKHz Flat and Program Weighting Curves C-MSG and 1SkHz Flat Weighting Curves Meter AMPLIFIER. Schematic No DETECTOR. Schematic NoPower Supply and Series Regulator Schematic No Factory Selected Values Section Maintenance IntroouctionInstrument Recommended Type Required Characteristics Model BAL ConversionFunction CARRIER, 75 Unbal Performance ChecksLevel Accuracy Checks TMS, TermFrequency Unbal Carrier Accuracy CheckRange 30Hz to 1MHz 100Hz to 600kHz 1MHz to 3MHzReturn Loss Check 20Hz to 20kHz 40Hz to 15kHz 100Hz to 20kHz 100Hz to 15kHzReturn Loss Test Set-Up Filter Response Checks Filter Response ChecksMSG dBm 3kHz Flat dBm 15kHz Flat dBm Program dBm TMS Brdg Input BalanceBridging Loss Input TMS BrdgUnbal Calibration Adjustment and Calibration ProcedurePower Supply Check Attenuator CalibrationCommon Mode Adjustment Frequency Response AdjustmentBalance Check Troubleshooting Procedures Assembly RemovalFilter Calibration Troubleshooting Tree Front Panel Trouble Analysis Dial BATRange Troubleshooting Front Panel TroubleshootingFunction Troubleshooting Front Panel Trouble Analysis ContdTroubleshooting the Meter Amplifier and Detector Troubleshooting Input AmplifierFilter Troubleshooting Defective FunctionTip to Ring Tip to Ground Ring to Ground Function Switch Resistance ValuesFunction Input Jacks DIAL/AC MON Jacks Brdg Term10. Resistance Checks 11. Factory Selected ValuesRange dBm Pin 1 to Pin 2 to Carrier 75 Unbal Level Accuracy Check Performance Check Test CardDescription Check Carrier 135 BAL Level Accuracy CheckPerformance Check Test Card Contd Carrier 600 BAL Level Accuracy CheckProgram Return Loss CheckFilter Response Checks MSG Bridging Loss CheckSection Replaceable Parts Introduction Ordering InformationReplaceable Parts 03555-66507 PC Board Assy functionReplaceable Parts Contd 03555-66508 Board Assy amplifierA3 Contd 03555-66506 PC Board Assy filter A4 Contd Chassis Mounted Components Chassis Mounted Components Contd MiscellaneousMiscellaneous Contd Fscm Replacement National Part Stock Number FscmPart Number National Stock Number Cross Reference Index National Stock NumberPage Model 3555B Appendix a Code List of Manufacturers Schematic Diagrams Circuit DiagramsFunctional Block Diagram Reference DesignationsSection Model 3555B Functional Block Diagram 7-4A1 Function Assembly Schematic and Component Location 7-67-8 A4 Filter Schematic and Component Location 7-1011/7-12 Appendix a ReferencesAppendix B Maintenance Allocation Section I. Introduction GeneralMaintenance Function Column EntriesTool and Test Equipment Requiremen ts Sec Remarks SecAudio Level Meter TA-885/U TM 11-7725-2779-14&P REF Code NumberManual Backdating Changes Appendix CTransmission and Noise Measuring SET Delete CR6 across M1 Government Printing Office 1980-603-128/66Major General, United States Army Adjutant General General, United States ArmyChief of Staff Active ArmyPage PIN