HP TM 11-6625-2779-14&P manual TM 11-7725-2779-14&P, REF Code Number

Page 78

TM 11-7725-2779-14&P

SECTION III. TOOL AND TEST EQUIPMENT REQUIREMENTS

FOR

AUDIO LEVEL METER TA-885/U

TOOL OR
TEST	MAINTENANCE		NATIONAL/	TOOL
EQUIPMENT	CATEGORY	NOMENCLATURE	NATO STOCK	NUMBER
REF CODE			NUMBER
1	H,D	OSCILLATOR SG-1128/U, HP #654A	6625-00-450-7590
2	H,D	OSCILLATOR AN/URM-127	6625-00-783-5965
3	H,D	TRANSFORMER (LINE MATCHING) MX-8385/U	6625-00-567-5837
4	H,D	MULTIMETER AN/USM-451	6625-01-060-6804
5	H,D	AMPLIFIER HP-467A	6625-00-458-2480
6	H,D	VOLTMETER, ELECTRONIC ME-30 E/U	6625-00-643-1670
7	O	COMMON TOOLS NECESSARY TO THE PERFORMANCE OF
		THIS MAINTENANCE FUNCTION ARE AVAILABLE TO
		MAINTENANCE PERSONNEL FOR THE MAINTENANCE
		CATEGORY LISTED.

B-4

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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 Illustrations List of TablesIii Maintenance Forms, Records, and Reports Section IntroductionScope Administrative Storage Destruction of Army Electronics MaterielReporting 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 CalibrationFrequency Response Adjustment Common Mode AdjustmentBalance Check Assembly Removal Troubleshooting ProceduresFilter 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 Term11. Factory Selected Values 10. Resistance ChecksRange 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 NumberAppendix C Manual Backdating ChangesTransmission 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