HP TM 11-6625-2779-14&P manual Specifications, Voice Frequency Level Measurements 20Hz to 20kHz

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Section I

Model 3555B

Table 1-1. Specifications

VOICE FREQUENCY LEVEL MEASUREMENTS (20Hz to 20kHz)

Range: -91dBm to +31dBm

Level accuracy: 20Hz to 20kHz: +0.5dB 40Hz to 15kHz: +-0.2dB (Levels greater than -60dBm)

Note: For levels greater than +1 dBm, level accuracy specification applies only for frequencies above 100Hz.

Input: will terminate or bridge 600 ohms or 900 ohms balanced.

Bridging loss: less than 0.3 dB at 1kHz.

Return loss: 30dB min. (50Hz to 20kHz) TERM

Return loss: 30dB min. (50Hz to 2kHz) TERM only.

Balance:

greater than 80dB at 60Hz greater than 70dB to 6kHz greater than 50dB to 20kHz

Holding circuit: 700 ohms dc resistance, 60mA max. loop current at 300Hz. With holding circuit in, above specs apply from 300Hz to 4kHz.

NOISE MEASUREMENTS

Range: -1 dBm to +121dBm

Weighting filters: 3kHz flat, 15kHz flat, C-message, and program. Meets joint requirements of Edison Electric Institute and Bell Telephone System.

Input: same as for level measurements.

Noise to ground:

80 kilohms across line

100 kilohms to ground

-40dB relative to 600 ohms noise metallic at 1kHz.

CARRIER FREQUENCY LEVEL MEASUREMENTS (30Hz to 3MHz)

Range: -61dBm to +11dBm

Level accuracy:

600 ohms balanced 1kHz to 150kHz: ±0.5dB

135 ohms balanced (or 150 ohms balanced) 1kHz to 600kHz: ±0.5dB

10kHz to 300kHz: ±0.2dB 75 ohms unbalanced

100Hz to 600kHz: ±0.2dB

30Hz to 1MHz: ±0.5dB

1MHz to 3MHz: ±0.5dB ±10% of meter reading in dBm.

Input: will terminate or bridge 600 ohms or 135 ohms

balanced and 75 ohms unbalanced. Return loss: TERM ONLY

600 ohms: 26dB min 3kHz to 150kHz

135 ohms: 26dB min to 600kHz

75 ohms: 30dB min to 3MHz Bridging loss: less than 0.05dB at 10kHz Balance:

greater than 70dB to 10kHz greater than 60dB to 100kHz greater than 40dB to 600kHz

GENERAL

Temperature range: 0°F to 120°F 0 to 95% relative humidity

The 3555B will operate at -40°F under reduced specifications. At this temperature, attention should be given to noting condition of battery as indicated on Battery Test (DIAL/BAT).

Meter: linear dB scale indicates rms value of input signal. 12dB range.

Meter response

Normal: 200ms to indicate a reading to 0dBm on meter.

Damp: 500ms to indicate a reading to 0dBm on meter.

Maximum input voltage

Tip to ring: 150V peak

Tip or ring to ground: 500V peak

(This is maximum instantaneous voltage. Input circuit will withstand 48V dc CO battery with superimposed 90V rms 20Hz ringing voltage or

±130V carrier supply.)

Maximum longitudinal voltage: 200V rms at 60Hz

AC Monitor: 0.27V rms for 0dBm on meter.

Rout = 8 kilohms. Available at DIAL/AC MON jacks. Sufficient to drive WE 1011B or 52 type headset.

DC Monitor: 1 volt for 0dBm on meter. Rout = 2 kilohms. Jack accepts 310 plug (tip negative).

Input jacks: will accept Western Electric (WE) 241, 309, 310, 358 plugs. Binding posts accept banana plugs, spade lugs, phone tips or bare wires. Removable shorting bar between sleeve and ground binding posts.

Dial/AC Monitor jacks: will accept WE 289, 310, 347 plugs. Accepts WE 1011B lineman's handset or 52 type headset.

Power requirements:

Internal battery: single NEDA 202 45V "B" battery included. Expected battery life - 180 hours at 4 hours per day at 70° F.

AC: 115V or 230V, 48-440Hz, <1W

External battery: 24V or 48V office battery; jack accepts 310 plug (tip negative) less than 15mA.

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Contents HEADQUARTERS, Department of the Army Reporting Errors and Recommending Improvements TM 11-6625-2779-14&PTechnical Manual Headquarters Department of the Army NSNReplaceable Parts Iii List of IllustrationsList of Tables Scope Maintenance Forms, Records, and ReportsSection Introduction Reporting Equipment Improvement Recommendations EIR Administrative StorageDestruction of Army Electronics Materiel Items Comprising an Operable Equipment Specifications Voice Frequency Level Measurements 20Hz to 20kHzSection Section General Information IntroductionAccessory Equipment Supplied Accessory Equipment SuppliedInstrument Identification BAL ModificationSection Installation Inspection Warranty ExceptionPower Requirements BatteryInstallation and Removal of Battery Cover RemovalControls Connectors Indicators BatterySection 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 Identifying Noise Characteristics Transmission Loss MeasurementsCrosstalk Measurements Crosstalk Correction FactorMeasurements in DBC Reinstall the set in its case 0dBmInput jacks are connected in parallel. If a 600 ohm 135 BALStep Procedure Level Measurement Noise Metallic MeasurementsNoise-to-Ground Measurements Balance Measurement Recorder CalibrationExample Transmission Loss MeasurementBlock Diagram Description Section Theory of Operation IntroductionDetailed Circuit Description Simplified Dial BAT FunctionInput Amplifier A3. Schematic No Range Attenuator A2Setting Attenuation FILTERS. Schematic NoRange Attenuator 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 Section Maintenance Introouction Instrument Recommended Type Required Characteristics ModelFactory Selected Values BAL ConversionPerformance Checks Level Accuracy ChecksFunction CARRIER, 75 Unbal TMS, TermUnbal Carrier Accuracy Check RangeFrequency 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 MSG dBm 3kHz Flat dBm 15kHz Flat dBm Program dBm Filter Response ChecksFilter Response Checks Input Balance Bridging LossTMS Brdg Input TMS BrdgAdjustment and Calibration Procedure Power Supply CheckUnbal Calibration Attenuator CalibrationBalance Check Frequency Response AdjustmentCommon Mode Adjustment Filter Calibration Assembly RemovalTroubleshooting Procedures Troubleshooting Tree Front Panel Trouble Analysis Dial BATFront Panel Troubleshooting Function TroubleshootingRange Troubleshooting Front Panel Trouble Analysis ContdTroubleshooting Input Amplifier Filter TroubleshootingTroubleshooting the Meter Amplifier and Detector Defective FunctionFunction Switch Resistance Values Function Input Jacks DIAL/AC MON JacksTip to Ring Tip to Ground Ring to Ground Brdg TermRange dBm Pin 1 to Pin 2 to 11. Factory Selected Values10. Resistance Checks Performance Check Test Card Description CheckCarrier 75 Unbal Level Accuracy Check Carrier 135 BAL Level Accuracy CheckPerformance Check Test Card Contd Carrier 600 BAL Level Accuracy CheckReturn Loss Check Filter Response Checks MSGProgram 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 Replacement National Part Stock Number Fscm Part Number National Stock Number Cross Reference IndexFscm National Stock NumberPage Model 3555B Appendix a Code List of Manufacturers Circuit Diagrams Functional Block DiagramSchematic Diagrams 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 ReferencesMaintenance Allocation Section I. Introduction General Maintenance FunctionAppendix B Column EntriesTool and Test Equipment Requiremen ts Sec Remarks SecAudio Level Meter TA-885/U TM 11-7725-2779-14&P REF Code NumberTransmission and Noise Measuring SET Appendix CManual Backdating Changes Delete CR6 across M1 Government Printing Office 1980-603-128/66General, United States Army Chief of StaffMajor General, United States Army Adjutant General Active ArmyPage PIN
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