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HP TM 11-6625-2779-14&P User's Manual

1. R TMS 1 7 30 dB lt 30 dB 20 dB 10 dB aA 9000 CAL R20 1 2 1 4 5 2 PF 1 4 9 2 PF 24 92 PF 5K lt 3 TO GRD WITH eae 500 3 Y BAL 24PF 47PF EE NE E 3 1 1 Senni crs DEPRESSED M RA RT T it 96 84 90K tot B F F r 5 GRO WITH OUTPUT OF 75 FUNCTION SWITCH did 590 2 1 7 1 UNBAL 3010 4280 2222 B 6000 CAL 500 nnl 20 GRD WITH 5 3 0 2 1 o 1 RI 7 cbe _ cee St DEPRESSED E 4 c34 22 R22 1 107 20 i 2 R67 o o 6000 CAL 28688 90 dBm CRI9 E R3 65 27 msi 518 Rel rig 82254 nen OR 1 62 R69 3 266K 3 266 ce 46 28K 62 KHz 865 430 13 i I A sx pe ORA 1 SIA R SiB R SIC R R3 02 ES R9 9 lt 5 wor R8 o o A2 RANGE ASSEMBLY lt i ina e 2 AND
2. mmn cu Am 4 6 en nm s MASKEN NNNNA HII TH m H 1 CURED 1L LEGEND C MESSAGE 15 FLAT IH HAIR LG ALLE EH u 35558 8 1853 100KHz OR V 3555 Model 3555 identical operation only the first will discussed detail 4 27 Referring td Figure 7 4 the signal is applied to the assembly through pin 22 If C MSG is selected the signal is first attenuated by A4R1 A4R2 and A4R3A Potentiometer A4R3A is for C MSG level adjustment for OdB at 1kHz The signal is then
3. u rotary pM no standard type number ground ed neon assigned selected or NO LL LED normally open selenium special type m henry ies PO negative positive zero M section s mercury 4 4 zero temperature coefficient i Sili E sod hertz cycle s per second Dupont de Nemours DECMAL MULTIPLIERS Prefix Symbols Multiplier Prefix Symbols Multiplier tear T 10 10 G 10 milli m 10 mega M or Meg 10 micro 109 kilo Kork 10 nano n 10 hecto h 10 pico p 102 10 femto f 1075 10 atto a 1078 DESIGNATORS transistor TS terminal strip QCR transistor diode vacuum tube bulb Bou M resistor photocell etc mm ned thermistor cable switch P Socket transformer XDS lampholder TB board XF fuseholder mechanical thermocouple crystal Poa test point ee network 6 1 Model 35558 Table 6 1 Replaceable Parts REFERENCE hp TQ DESCRIPTION MFR MFR PART NO DESIGNATOR PART NO A1 03555 66507 1 PC Board Ass y function hp C1 0170 0055 1 C fxd mylar 0 1uF 20 200 56289 192P10402 PTS C2 C3 0180 0089 2 C fxd Al elec
4. 4 Filter Schematic and Component Simplified Average Detection LOCATON 7 9 7 10 3kHz FLAT PROGRAM A3 Meter Amplifier Detector and Series Weighting Regulator Schematic Component C MSG and 15kHz FLAT Weighting Curves 4 6 LIST 5 Number Page Number Page Specifications L 1 0 5 1 Required Test Equipment Em Accessory Equipment Supplied 1 2 5 2 75 UNBAL Carrier Accuracy Suitable Batteries Meeting 5 3 Carrier 600 BAL and 135 BAL Level NEDA 202 Specifications 2 1 Accuracy 5 3 Front Side and Rear Panel Controls 5 4 VF Nm Level Accuracy Checks 600 BAL Indicators and Connectors 3 3 8 and 900 BAL 80 dBm Through 30 dBm Filter Response 5 6 Front Panel Trouble Analysis Function Troubleshooting FUNCTION Switch Resistance Values Balance Measurement Range Attenuation Amplifier Gain 5 16 Recorder Calibration Resistance Checks 5 16 Transmiss
5. attenuation for longitudinal noise For carrier frequencies 600 ohm 135 ohm and 75 ohm impedances are provided The 600 and 135 function can be either balanced or unbalanced bridged or terminated The 75 function is unbalanced only Bridging impedance is over 100 kilohms allowing measurements with a bridging loss of less than 0 05dB The meter indicates in dBm for any selected input impedance 1 4 35558 includes flat C Message a Program 15kHz flat filter each easily selectable by a front panel control These filters conform to the standards set up by the Bell System and Edison Electric Institute Other filters are available upon request Figure 1 1 Model 3555B Transmission and Noise Measuring Set 1 1 Section 1 5 noise to ground Ng function is included which permits the measurement of longitudinal noise When making noise to ground measurements the impedance between INPUT terminals is greater than 80 kilohms is 100 kilohms between each terminal and ground A HOLD function permits holding the line while noise measurements are being made The input circuitry provides 40dB of longitudinal noise attenuation when noise to ground measurements are being made 1 6 A DIAL BAT function permits connecting a lineman s handset to the line for the purpose of dialing and at the same time connects the front panel meter to the power supply so that the battery voltage or unr
6. 3 Ec EE RN TII 3 Level and noise measurements Level 3 Noise Recorder compatibilily UL EC MEM Transmission loss SECTION M APPENDIX A APPENDIX SECTION IV APPENDIX C OPERATING INSTRUCTIONS Cont Crosstalk Identifying noise nennen Measurements in cd sets edat Duc voee cada dcr ta d eie Measurement 150 BAL conversio EM THEORY OF OPERATION INTRODUCTION Block diagram descriptions Detailed circuit description Range attenuator Input amplifier gira 4 4 Meter amplifier neris c EL Ra ELI M Mte Power supply and series regulator nnns MAINTENANCE Introduction Factory selected 150 BAL conversi
7. Hudson Falls N Y 01009 Alden Products Co Brockton Mass 01121 Allen Bradley Milwaukee Wis 01255 Litton Industries Inc Beverly Hills Cal 01281 TRW Semiconductors Inc Lawndale Cal 01295 Texas Instruments Inc Transistor Products Dalas Texas 01349 Alliance Mfg Alliance Ohio 01538 SmallPartsInc Los Angeles Cal 01589 Pacific Relays Inc Van Nuys Cal 01670 Gudebrod Bros Silk New York N Y 01930 Amerock Corp Rockford 01960 Pulse Engineering Santa Clara Cal 02114 Ferroxcube Corp of Saugerties 02116 Wheelock Signals Inc Long Branch N J 02286 Cole Rubber and Plastics Inc Sunnyvale Cal 02660 Amphenol Borg Electronics CORPS egere Broadview Ill 02735 Radio Corp of America Semi conductor and Materials Division Somerville N J 02771 Vocaline Co of America Ine er Eos Old Saybrook Conn 02777 Hopkins EngineeringCo San Fernando Cal 02875 Hudson Tool amp Newark N J 03296 Nylon Molding Springfield N J 03508 G E Semiconductor Prod Dept d Syracuse N Y 03705 Apex Machine amp Tool Co Dayton Ohio 03797 Eldema Corp Compton Calif 03818 Parker Seal Los Angeles Cal 03877
8. Sos NOTE 20 WIRE DESTINATIONS 1 Some earlier instruments did not have 2 6 56 Refer to Appendix change 4 i for backdating NUMBER NUMBER 2 and 2 were located at a different place in some earlier instruments Refer to Appendix C change 1 for back dating Figure 7 5 A3 Meter Amplifier Detector and Series Regulator Schematic and Component Locations 7 11 7 12 310 4 310 7 11 6625 320 12 11 6625 683 15 11 6625 2953 14 38 750 740 90 1 750 244 2 APPENDIX 5 Index of Technical Manuals Technical Bulletins Supply Manuals Types 7 8 and 9 Supply Bulletins and Lubrication Orders US Army Equipment Index of Modification Work Orders Operator s and Organizational Maintenance Manual Voltmeters ME 30A U and voltmeters Electronic ME 30B U ME 30C U and ME30E U Operator s Organizational Direct Support General Support and Depot Maintenance Manual Signal Generator AN URM 127 NSN 6625 00 783 5965 Operator s Organizational Direct Support and General Support Maintenance Manual Multimeter AN USM 451 NSN 6625 01 060 6804 The Army Maintenance Management System 5 Administrative Storage of Equipment Procedures for Destruction of Electronics Materiel to Prevent Enemy Use Electronics Command A 1 APPENDIX MAINTEN
9. 11 6625 2779 14 amp TECHNICAL MANUAL OPERATOR S ORGANIZATIONAL DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL INCLUDING REPAIR PARTS AND SPECIAL TOOLS LISTS FOR METER AUDIO LEVEL TA 885 U HEWLETT PACKARD MODEL 3555B NSN 6625 00 255 1083 HEADQUARTERS DEPARTMENT OF THE ARMY 11 MARCH 1980 11 6625 2779 14 amp P This manual contains copyrighted material reproduced by permission of Hewlett Packard Company All rights are reserved TECHNICAL MANUAL HEADQUARTERS DEPARTMENT OF THE ARMY No 11 6625 2779 14 amp P WASHINGTON DC 77 March 1980 OPERATOR S ORGANIZATIONAL DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL INCLUDING REPAIR PARTS AND SPECIAL TOOLS LISTS FOR METER AUDIO LEVEL TA 885 U HEWLETT PACKARD MODEL 3555B NSN 6625 00 255 1083 REPORTING ERRORS AND RECOMMENDING IMPROVEMENTS You can help improve this manual If you find any mistakes or if you know of a way to improve the procedures please let us know Mail your letter or DA Form 2028 Recommended Changes to Publications and Blank Forms or DA Form 2028 2 located in back of this manual direct to Commander US Army Communications and Electronics Materiel Readiness Command ATTN DRSEL ME MQ Fort Monmouth NJ 07703 In either case a reply will be furnished direct to you This manual is an authentication of the manufacturer s commercial literature which through usage has been found to cover the data required to operate
10. Anaheim Cal Philco Corporation Lansdale Division eS E Lansdale Pa Western Fibrous Glass Products wai Francisco Cal Van Waters n Rogers Inc San Francisco Cal Tower Mfg Corp Providence R 1 Cutler Hammer Inc Lincoln Ill Gould National Batteries Inc St Paul Minn General Mills Inc Buffalo N Y Graybar Electric Oakland Cal G E Distributing Corp Schenectady N Y Security Detroit Mich United Transformer Co Chicago Ill United Shoe Machinery Corp Beverly Mass U S Rubber Co Consumer Ind amp Plastics Prod Div Passaic N J Belleville Speciality Tool Mfg Inc PEE Belleville Ill United Carr Fastener Corp Chicago Ill Bearing Engineering Co San Francisco Cal ITT Cannon Elect Inc Salem Div ee n n mn n n nn nn Salem Mass Connor Spring Mtg San Francisco Cal Miller Dial amp Nameplate Co El Monte Cal Radio Materials Co Chicago Augat Inc Attleboro Mass Dale Electronics Inc Columbus Nebr Elco Corp Willow Grove Epiphone Inc New York Gremar Mfg Inc Wakefield Mass K F Development Co Redwood City Cal Malco Mfg Inc BEPERKEN Chicago CODE LIST OF MANU
11. Kansas City Kansas Newbury Park Calif Resistor Santa Cal American Components Inc Conshohocken Pa ITT Semiconductor a Div of Int Telephone and Telegraph Corporation West Palm Beach Hewlett P ckard Company Loveland Colo Cornell Dublier Electric Newark N J Corning Gl ss Works Corning N Y Electro Cube San Gabriel Cal Williams Mfg Co San Jose Cal The Little Falis N J Webster Electronics New York N Y Scionics 2 Northridge Cal Adjustable Bushing Co N Hollywood Cal Micron Electronics Garden City Long Island N Y Amprobe Inst Corp Lynbrook N Y Cabletronics Costa Mesa Cal Twentieth Century Coil ring Santa Clara Cal Fenwal Elect Framingham Mass Ine Mountain View Cal Spruce Pine Mica Co Spruce Pine Omni Spectra Inc Detroit Ill Computer Diode Corp Lodi N J Electroid Co Union N J Boots Aircraft Nut Corp Pasadena Cal Ideal Prec Meter Inc De Jur Meter Div Brooklyn N Y Delco Radio Div of M Corp Kokomo Ind Thermonetics Inc Canoga Park Cal Company Mountain View Ham
12. Model 3555B Specifications balanced and 75 ohms unbalanced Return loss TERM ONLY 600 ohms 26dB min 2 to 150kHz 135 ohms 26dB min to 600kHz 75 ohms 30dB min to 2 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 35558 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 OdBm on meter Damp 500ms to indicate a reading to OdBm 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 27 rms for 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 OdBm on meter Rou 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 Remova
13. VIEWED FROM THE COMPONENT SIDE OF BOARD WAVEFORM AND VOLTAGE MEASUREMENTS WERE MADE WITH RESPECT TO CHASSIS GROUND USING A HIGH INPUT IMPEDANCE GREATER THAN 1 OSCILLOSCOPE AND TRANSISTOR VOLTMETER VOLTAGE LEVELS SHOWN ARE NOMINAL AND MAY VARY SOMEWHAT FROM ONE INSTRUMENT TO ANOTHER A VARIATION OF 10 IN MEASUREMENTS SHOULD ALLOWED 7 2 750 750 ASCB ADJ TERMINATIONS INPUT CONDITIONS FUNCTION FILT FLAT 600 841 INPUT FLAT TERM LEVEL OdBm 775 IKHz RANGE ATTENUATOR INPUT AMPLIFIER 775V RMS IKHz 2045mV RMS CARRIER 1351 CAL IKHz 26 6000 CAL A3R20 80 dBm 9000 CAL IKHz 5 A3C30 012 014 i INPUT INPUT TMS XA3 9 5 55 2 RMS 6 4 5 401 04 A407 QIO A4Q15 Q18 A4QI9 Q2 AC OUTPUT 27 1 270mv RMS FOR INPUT 048 ON METER IRMS C MSG ADJ IKHz OdBm A4R3D MSG ADJ 3KHz 2e 5d8m A3CRIG W 6 A405 06 A3R3B PROG ADJ KHz Od8m 4 VOLTAGE t 1 1 1 5 FLAT A4R3C 3KHz IS5KHz FLAT ADJ 1KHz OdBm MI AU esj 310 IV FOR 098 DC MON METER DEFLECTION 9 NORM Ril 2320 RESPONSE 55 DIAL AC MON Figure 7 1 Fu
14. ea DENS Rochester N Y Products Co of America Chicago Amatom Electronic Hardware Co Inc New Rochelle N Y Beede Electrical Instrument Co Ie sua eua Penacook N H General Devices Co Indianapolis Ind Components Inc Ariz Phoenix Arizona Torrington Mfg Co West Div Van Nuys Cal Varian Assoc Etmac Div San Carlos Cal Kelvin Electric Van Nuys Cal Digitran Co Cal Transistor Electronics Minneapolis Westinghouse Electr c Corp Electronic Tube Div Elmira N Y Filmohm York N Y Cinch Graphik Co City of Industry Cal Silicon Transistor Corp Carle Place N Y Avnet Culver City Cal Fairchild Camera amp Inst Corp Semiconductor Div Mountain View Cal Minnesota Rubber Co Minneapolis Minn Birtcher Corp The Monterey Park Cal Sylvania Elect Prod Inc Mt View Operations Technical Wire Products i i Cranford N J Bodine Elect Chicago 11 Continental Device Corp Hawthorne Cal Raytheon Mfg Co Semi conductor Div Hewlett Packard Co New Jersey Division Rockaway N J U S Engineering Los Angeles Cal Blinn Delbert Pomona Cal
15. CB1541 CB1805 CB2211 CB2221 CB3921 CB4731 CB6821 CB8211 CB8221 EAC 301 MDL15 100 MPS 3563 MT 331 MT 332 B MT 3428 RD5288 SKA1 124 SPS3322 SPS361 1 SPS3612 553651 TAS396K015PIC TYPE GA TYPE LN821 0698 4521 LLA 1014A 11A 1242A 150D107X0010R2D 19C251AL CDH 192P10402 PTS 2N2904A 2600 1W 78PCG5 80994 HB 01121 01121 01121 01121 01121 01121 01121 01121 01121 01121 01121 82389 71400 04713 82389 82389 82389 07933 01295 04713 04713 04713 04713 37942 78488 04713 28480 82389 82389 56289 56289 56289 04713 71286 74868 04009 5905 00 989 8653 5905 00 254 7432 5905 00 726 5345 5905 00 833 0718 5905 00 721 0131 5905 00 726 6433 5905 00 755 0795 5905 00 985 5609 5905 00 721 0671 5905 00 755 0796 5905 00 721 0674 5935 00 233 6728 5920 00 665 3074 5961 00 122 8671 5935 00 201 8993 5935 00 192 4825 5935 00 500 7439 5961 00 222 6128 5961 00 137 4608 5961 00 224 5601 5961 00 137 0966 5961 00 137 0967 5961 00 137 0999 5910 00 816 2474 5910 00 577 1219 5961 00 804 7548 5905 00 489 2050 5930 00 402 6752 5930 00 406 8746 5910 00 850 0830 5910 00 852 2644 5910 00 797 9742 5961 00 941 2056 5325 00 449 3024 5935 00 919 6391 5930 00 929 1970 6 10 RCR07G100JS RCRO7G104JS RCR07G154JS RCR07G180JS RCR07G221JS RCR07G222JS RCR07G392JS RCR07G473JS RCR07G682JS RCR07G821JS RCR07G822JS F03B250V15 100A JJ086 RD5288 M39003 01 2979 81349 81349 81349 81349 81349 81349
16. FLAT and note the meter indication If it differs from the indication set up in step c adjust A4R3C to split the difference between these two indications e Change the 35558 NOISE WTG switch to C MSG and adjust A4R3A for OdBm indication on the 3555B meter f Change the 654A frequency to 3 00kHz and adjust A4R3D for an indication of 2 15dBm on the 3555B meter g Repeat steps e and f until both points are within specifications h Change the 3555B NOISE WTG switch to PROG and change the 654A frequency back to 1 001Hz with the output level still set to OdBm Adjust A4R3B for OdBm indication on the 3555B meter 5 25 ASSEMBLY REMOVAL 5 26 To gain access to the various assemblies in the 3555B use the following procedure a Turn the set off and remove it from the case by removing four front panel screws Unplug the small cable on the assembly 5 10 Model 3555B c Remove the two screws that secure the A3 board d Gently lift up the bottom of the A3 board to unplug it from the A1 FUNCTION assembly e Hold the bottom of the A3 board high enough to clear the FUNCTION board and pull the A3 assembly out This is easily accomplished by gently rocking the board back and forth while pulling it down toward the FUNCTION board f Once the A3 assembly has been removed the Al FUNCTION board can be removed by pulling it out g To gain access to the RANGE attenuator A2 Input switch and the NOISE WTG switch the
17. R68 0698 4503 1 R fxd met flm 66 5 kilohms 1 1 8W 91637 MF 1 10 32 obd R69 0698 4491 1 R fxd met flm 30 9 kilohms 1 1 8W 91637 MF 1 10 32 obd R70 R71 06841001 R fxd comp 10 ohm 10 1 4W 01121 001 R72 0684 2701 fxd comp 27 ohm 10 1 4W 01121 CB2701 R73 0684 1021 fxd comp 1000 ohm 10 1 4W 01121 CB1021 R74 R75 0684 8221 2 R fxd comp 8200 ohm 10 1 4W 01121 CB8221 XA1 1251 1941 1 Connector PC 6 pin 71785 252 06 30 310 W1 0355 61616 1 Cable hp A4 03555 66506 1 PC Board filter hp C1 0140 0177 1 C fxd mica 400pF 1 72136 RDM15F3C C2 0180 0291 4 fxd Ta elect 1uF 10 35 56289 150D105X9035A2 DYS C3 C4 0160 2130 C fxd mice 865pF 1 100 72136 RDM15F 865 F1C C5 0140 0203 5 C fxd mica 5 72136 RDM15F421F3C C6 0180 0228 C fxd elect 22uF 10 15 vdcw 37942 TAS226K015PIC C7 0140 0163 6 C fxd mice 4751pF 1 300 vdcw 72136 RDM20F 4751 F3S C8 0160 3024 4 C fxd mica 1700pF 1 100 vdcw 72136 RDM19F 72215 C9 0140 0203 C fxd mice 30pF 5 72138 RDM15F421F3C C10 0160 3024 C fxd mice 1700pF 1 100 vdcw 72138 RDM19F172F1S C11 0180 0228 C fxd elect 22uF 10 15 vdcw 37942 TAS226KOIPIC C12 0140 0163 C fxd mica 4751pF 1 300 vdcw 72136 RDM20F 4751 F3S C13 thru C15 Not assigned C16 0160 3024 C fxd mice 1700pF 1 100 vdcw 72136 RDM19F172F1S C17 0140 0203 C fxd mica 30pF 5 72136 RDM15F421F3C C18 0160 3024 C fxd mica 1700pF 1 100 vdcw 7213
18. Se Switching RANGES 1 2 3 4 30 X X x 20 X X x 10 X X 0 x x 10 x x 20 30 x 40 50 60 A2R13 A2R14 70 A2R13 80 Ranges Affected 30 20 30 20 60 70 If Defective 20 0 10 10 30 30 40 50 thru 30 60 70 80 Designator Purpose C4 Adjust balance at 600kHz 135 BAL A1C5 Padding capacitor for A1 C4 A1C9 Adjust balance 20kHz 600 BAL VF Nm A1C8 Padding capacitor for A1C7 A1C10 and Frequency response correction for A1TI A1R12 A1R14 600 BAL VF Nm calibration A3C1 Padding capacitor for A2C12 15 Frequency response 20 2 80dBm 600 BAL VF Nm A3R46 Adjust the bias level for A3Q10 10V at side of A3C24 A3R72 Response 20Hz 600 BAL VF Nm 70dBm and 20Hz 900 BAL 0dBm Compromise between these two settings A3R74and Meter tracking at 1 3 full scale Resistors A3R75 should be the same value Table 5 10 Resistance Checks RANGE dBm Pintto3 Pin2to3 ______ 1 2 154 kilohms 13 kilohms 2 33 kilohms 0 28 64 28 64 kilohms 28 64 kilohms Infinity 41 6 kilohms 31 kilohms 28 64 kilohms CHECK TEST CARD Hewlett Packard Model 3555B Transmission and Noise Measuring Set Serial No Tests Performed By Date DESCRIPTION CHECK CARRIER 75 UNBAL LEVEL ACCURACY CHECK 30Hz to 1MHz 10dBm Range OdBm Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dB
19. Si NPN 2N3391 01295 SKA1124 Q13 1853 0086 TSTR Si PNP 2N50B7 04713 SPS 3322 Q14 thru Q16 1854 0071 TSTR Si NPN 2N3391 01295 SKA1124 017 1853 0086 TSTR Si 2 5087 04713 5 5 3322 18 thru 020 1854 0071 TSTR Si 2N3391 01295 SKA1124 Q21 1853 0086 TSTR Si PNP 2N5087 04713 SPS 3322 Q22 1854 0071 TSTR Si NPN 2N3391 01296 SKA1124 R1 0757 0450 2 R fxd et flm 22 1 kilohms 1 118W 75042 CEA obd R2 0038 4412 1 fxd met flm 17 4 kilohms 1 1 8 91637 MF 1 10 32 obd R3 2100 0406 1 R var carbon comp 5 kilohms 30 4 sec 71590 Series 5 Type 70 4 R4 0698 7373 1 fxd met flm 98 941 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R5 R6 0698 7374 2 fxd met flm 217Jkilohms 0 1 1 8W 91637 CMF 1 10 32 obd R7 A B C 1810 0027 5 carbon flm network 2 10 kilohms 10 56289 178C5 R8 0698 7372 1 R fxd met flm 108 94 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R9 0698 7376 1 fxd met 11 397 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R10 0698 6313 5 fxd met flm 20 kilohms 0 1 118W 91637 CMF 1 10 32 obd R11 0698 7375 fxd met flm 28 640 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R12 R13 0757 0476 2 fxd met flm 301 kilohms 1 1 8W 14674 C4 obd R14 0684 6821 1 fxd comp 6800 ohms 10 1 4 01121 CB6821 R15 0604 4731 fxd comp 47 kilohms 10 11 4W 01121 84731 R16 0698 3557 1 fxd met flm 806 ohms 1 1 8W 14674 C4 obd R17 0698 3519 1 R fxd met flm 12 4 kilohms 1 1 8W 91637 MF 1 10
20. Transitron Electric Corp Wakefield Mass 03888 Pyrofilm Resistor Co Ine Cedar Knolis N J 03954 Singer Diehl Div Finderne Sumerville N J 04009 Arrow Hart and El ct Hartford Conn 04013 Taruus Corp Lambertville N J 04062 Arco Electronic 100 Great Neck N Y 04217 Essex Wire Los Angeles Cal 04222 Hi Q Division of Aerovox Myrtle Beach S C 04354 Precision Paper Tube Co Wheeling Ill 04404 Palo Alto Division of Hewlett Packard Palo Alto Cal 04651 Sylvania Electric Products Microwave Device Div Mountain View Cal 04673 Dakota Engr Inc Culver City Cal 04713 Motorola Inc Semiconductor Prod Div Phoenix Arizona 04732 Filtron Co Western Div 2 Culver City Cal 04773 Automatic Electric co PE Northlake 04796 Sequoia Wire Co Redwood City Cal 04811 Precision Coil Spring Co El Monte Cal 04870 Motor Westchester 04919 Component Mfg Service os P W Bridgewater 05006 Twentieth Century Plastics Los Angeles 05277 Westinghouse Electric Corp Semiconductor Dept Youngwood 00015 49 CODE LIST OF MANUFACTURERS The following code numbers are from the Federal Supply Code for Manufacturers Cataloging Handbooks H4 1 Name to Code and 4 2 Co
21. procedure at a frequency of 10kHz The 400FL indication should not drop by more than 0 05dB Change the equipment setup by connecting a 300 ohm 1 resistor in series with the 400FL input and change the resistor connected across the 400FL input to 900 ohms 1 TEST SC 6000 FEED THRU TERMINATION piio95A HH 35538 8 490 Section V With the 400FL set to the OdB range adjust the 654A output level for exactly OdB indication on the 400FL Change the 3555B FUNCTION to VF Nm 900 and connect the 3555B input to the 400FL input terminals The 400FL indication must not drop by more than 0 3dB INPUT BALANCE a Set the 3555B controls as follows FUNCTION VF Nm 600 INPUT TMS BRDG RANGE 0dBm Connect the 654A 600 ohm output to the tip and ring input of the 35558 Set the output frequency of the 654 to 60Hz and adjust the amplitude control for OdBm indication on the 3555B meter Change the equipment setup to that shown in Figure 5 7 Change the 3555B RANGE switch to 80dBm The 3555B indication meter RANGE setting must be down at least 80dB Change the 3555B RANGE switch to 70dBm and tune the 654A to 6kHz The 3555B indication must be down at least 70dB Change 3555B RANGE to 60dBm and tune the 654A to 20 2 The 35558 indication must be down at least 50dB Change the 3555B FUNCTION switch to hp3555B TRANSMISSION 8 NOISE MEAS
22. 0 2dBm Sed Paragraph 5 35 LEVEL 40dBm LEVEL 500dBm LEVEL 60dBm LEVEL 70dBm LEVEL 80dBm LEVEL 0dBm NG CHECK 75 UNBAL Connect UNBAL signal Change RANGE to 400dBm Change RANGE to 50dBm Change RANGE to 60dBm Change RANGE to 70dBm Change RANGE to 80dBm RANGE to 0dBm INPUT TMS TERM RANGE 0dBm FUNCTION VF Nm 600 BAL 40dBm 0 2dBm 50dBm 0 2dBm 60dBm 0 2dBm 70dBm 0 2dBm 80dBm 0 2dBm Sed Paragraph 5 35 between tip and ring Change input connection Connect signal between tip and ring and sleeve tip and ring shorted together ground lead to sleeve Depress NG button Change RANGE to 40dBm Some meter jitter may be experienced but the reading should be within the tolerance indicated Measure 270mV 0 2dBm jacks Paragraph 5 38 Adjust oscillator level for OdBm on 3555B meter 40dBm Refer to Table 5 8 c Schematics The schematic diagrams contain dc voltage levels and signal levels for a specified input condition This will assist in troubleshooting individual circuits 5 31 FRONT PANEL TROUBLESHOOTING 5 32 Before attempting to troubleshoot the set first determine from the front panel controls exactly which functions are performing properly and which ones are not In this way many troubles can be isolated to a specific area and sometimes to a component 5 33 Table 5 6 a step by step procedure for check
23. 1 8W 91637 CMF 1 1032 obd R42 R43 0698 7369 2 fxd met flm 73803 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R44 A B C 1810 0027 R carbon flm network 2X100K 10 kilohms 10 56289 178C5 R45 0698 7368 1 fxd met flm 36 901 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R46 0698 6943 fxd met flm 20 kilohms 0 1 91637 CMF 1 10 32 obd 6 6 Model 35558 Section Table 6 1 Replaceable Parts Cont d REFERENCE hp TQ DESCRIPTION MFR MFR PART NO DESIGNATOR PART NO 4 Cont d R47 0698 7370 1 fxd met flm 17 579 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R48 0684 1051 R fxd comp 1 megohm 10 1 4W 01121 CB1051 R49 0684 1021 fxd comp 1000 ohms 10 1 4 01121 CB1021 03565 60104 1 Chassis Ass y power supply hp CHASSIS MOUNTED COMPONENTS BT1 1420 0026 1 Battery 45V 83740 No 482 C1 0180 2230 1 fxd A1 elect 150uF 10 100 200 vdcw 56289 62D10046 DFP C2 0180 0149 1 C fxd A1 elect 65uF 60 vdcw hp C3 0180 0393 fxd Ta elect 39uF 10 10 vdcw 37942 TAS396K010P1C C4 0160 0987 1 C fxd mica 12pF 5 72136 RDM15C120J5S C5 0150 0023 1 C fxd cer 20000F 20 1000 vdcw 56289 20C295A2 CDH C6 0160 0195 1 C fxd cer 1000 pF 2095 250 vac 56289 19C251A1 CDH CR1 4 1901 0025 4 Diode Si 100 wiv 12pF 100mA 24446 55410 CR6 1901 0040 1 Diode Si 30 V 50 hp DS1 DS2 2140 0298 2 Neon lamp 74276 A230 F1 2110 0320 2 Fuse 0 15A 125V Slo Blo 71400 MDL 15 100 1400 0085 2
24. 20dBm 20 0 5 20 0 2 30dBm 30 0 5 30 0 2 40dBm 40 0 5 40 0 2 50dBm 50 0 5 50 0 2 Section V Table 5 2 75 UNBAL Carrier Accuracy Check the 3440A 3445A and reconnect the output of the 654A to the input of the 3555B Maintain the 654A meter reference throughout the remainder of the following checks The 35558 meter should indicate 0 1 dBm Check all the RANGES and frequencies listed in Table 5 2 for the specified tolerances Be sure to maintain the 654A reference established in step b Change the 654A to 600 BAL and change the 3555B to CARRIER 600 BAL Connect the 654A 600 BAL output to the 3555B input using a balanced cable f heck the RANGES and frequencies in Table 5 3 using the same procedure g described for the 75 UNBAL function Change the 654A to 135 BAL and change the 3555B to 135 BAL Repeat step e for the same RANGES tolerances indicated for the CARRIER 600 BAL function in Table 5 3 Change the 3555B to VF Nm 600 BAL and change the 654A to 600 BAL Check the 10dBm thru 80dBm ranges Table 5 4 for the tolerances indicated Change the 3555B to 900 BAL and connect a 150 ohm 1 resistor in series with each input lead Readjust the 654A for OdBM Repeat the checks in Table 5 4 for the same tolerances To check the top two ranges connect the equipment as shown in Figure 5 3 Bnd set the 3555B controls as follows FUNCTION VF Nm 600 BA
25. 20uA line to the right until it intersects the top line at 48 kilohms The value of R1 will then be 48 kilohms 2 kilohms input impedance 46 kilohms 3 44 Recorders with input characteristics that fall above the compatibility area in Figure 3 4 bannot be used to monitor the 3555B dc output since full scale deflection of the recorder cannot be accomplished by the 3555B 35558 DC MON z RECORDER INPUT OUTPUT 22 Figure 3 3 Matching 35558 Recorder 3 45 APPLICATIONS 3 46 Sometimes it is necessary to transmit send tone on a line and then measure the received signal coming back on the same line Rather than change connections back and forth between the 3555B and 236A Oscillator when changing from SEND to RECEIVE and thus take a chance on dropping the line it is much more convenient to make one set of connections and then select SEND or RECEIVE by means or a switch Refer to 3 47 By utilizing the test set up shown irl Figure 3 5 send and receive can be accomplished with a minimum number of operations To dial set both function switches to DIAL and dial the desired line on the butt in To send change the 3555 Section RECORDER 5 RECORDER FULL SCALE 3555 8 1177 Figure 3 4 Recorder Compatibility Chart hp35558 OSCILLATOR TRANSMISSION NOISE hp 236A MEASURING SET PATCH CORD Fi
26. 45 volts when new to 24 volts at cut off which is the end of useful life The cut off voltage corresponds to the left end of the green BAT GOOD area on the meter The condition of the battery and the approximate time to cut off can be estimated by observing the position of the meter pointer in the BAT GOOD area 3 10 The internal battery is of the carbon zinc type with its attendant limitations due to temperature The service obtained from carbon zinc batteries depends on factors such as current drain discharge temperature discharge time and storage prior to use The battery supplied with the 3555B should provide in excess of 180 hours of operation based on a 4 hours day duty cycle at 77 F 25 C At other temperatures this time will change At temperatures above 131 F 55 the batteries may fail suddenly while at temperatures below 40 F 20 C the service life will be short Section 3555 5 5 NORM RANGE dBrn f 77 48m 50 30 PPM 20 60 BROG FUNCTION mmm PER MON 309 75 30 347 3555A C 781 Figure 3 1 Front Panel Controls Indicators and Connectors 3 2 3555 Section Table 3 1 Front Side Rear S and G Jacks Binding posts accepting banana plugs spade lugs phone tips or bare wires for connection to the case ground G and sleeves S of all INPUT ja
27. 5dBm 1dBm 1kHz OdBm Ref 2kHz 1 3dBm 1dBm 2 5kHz 1 4dBm 2dBm 4kHz 14 5dBm 3 5kHz 28 5dBm 3dBm 2 FLAT 60Hz 1 75dBm 250Hz 1dBm 1kHz OdBm Ref 2kHz 0 5dBm 1 75dBm 2 5kHz 1 5dBm 2dBm 3kHz 3dBm 3dBm 15kHz FLAT 60Hz 1 75dBm 250Hz 1 1kHz OdBm Ref 5kHz 1dBm 10kHz 0 5dBm 1 75dBm 12 5kHz 1 5dBm 2dBm 15kHz 3dBm 3dBm PROGRAM 200Hz 17 3dBm 2 500Hz 6 6dBm 1dBm 1kHz OdBm Ref 2kHz 4 8dBm 2dBm 4kHz 6 5dBm 2dBm 5kHz 6 5dBm 2dBm 6kHz 6 4dBm 3dBm 8kHz 4dBm 3dBm 10kHz 8 5dBm 4dBm BRIDGING LOSS CHECK F Nm 900 BAL tkHz 0 3dBm VF Nm 600 BAL 1kHz lt 0 3dBm CARRIER 600 BAL 10kHz lt 05dBm INPUT BALANCE CHECK VE Nm 600 BAL 60Hz gt 80dB 6kHz gt 70dB 20kHz gt 50dB CARRIER 600 BAL 1 2 to 10kHz gt 70dB 1 2 to 100kHz gt 60dB 1 2 to 600kHz gt 40dB 3 3555 Section SECTION REPLACEABLE PARTS 6 1 INTRODUCTION 6 2 This section contains information for ordering replacement parts Table 6 1 lists parts in alphameric order of their reference designators and indicates the description hp part number of each part together with any applicable notes and provides the following a Total quantity used in the instrument TQ column The total quantity of a part is given the first time the part number appears b Description of the part See list of abbrevi
28. 600kHz 10kHz 300kHz 600 1kHz 150kHz 10kHz 100kHz Increase specification by 0 135 ohms or 150 ohms when not battery powered Section V AUDIO OSCILLATOR hp 201C DIGITAL VOLTMETER p 3440A 5 10 RETURN LOSS CHECK a b To make a return loss check it will first be necessary to construct a balanced bridge utilizing 0 1 resistors for each of the four 35558 impedances Figure 5 4 shows the equipment test set up to be used For this check to be meaningful all test leads should be kept short The leads connecting the 3555B to the bridge should be short clip leads and should be kept away from each other and from other leads Keep all the instruments away from other instruments that may be referenced to earth ground Connect the equipment as shown Figure 5 4 and set the 3555B controls as follows Model 3555B hp 35558 TRANSMISSION amp NOISE MEASURING SET 35558 8 2520 FUNCTION VF Nm 600 BAL INPUT iiie TMS TERM RANGE nee The 35558 does have to turned for this check at any frequency the 3555B return loss check is out of specification check the reference at that frequency as described in the following procedure C Set the 654 frequency to 1kHz Temporarily close 51 Figure 5 4 and adjust the 654A output level for an up scale indication on the 400FL AC Voltmeter Table 5 4 VF Nm Level A
29. 6804 AMPLIFIER HP 467A 6625 00 458 2480 VOLTMETER ELECTRONIC ME 30 E U 6625 00 643 1670 COMMON TOOLS NECESSARY TO THE PERFORMANCE OF THIS MAINTENANCE FUNCTION ARE AVAILABLE TO MAINTENANCE PERSONNEL FOR THE MAINTENANCE CATEGORY LISTED 000 Model 3555 APPENDIX MANUAL BACKDATING CHANGES Model 3555B TRANSMISSION AND NOISE MEASURING SET This manual backdating sheet makes this manual applicable to earlier instruments Instrument component values that differ from those in the manual yet are not listed in the backdating sheet should be replaced using the part number given in the manual Instrument Serial Prefix Make Manual Changes Instrument Serial Prefix Make Manual Changes 916 00500 and below 916 00509 and below 953 00544 and below 0992A03537 and below 7 953 00825 below 0992401395 below 0992403536 below Change 1 In instruments with S N 916 00500 below 2 the power supply were located as shown the following figure Change No 2 Table 6 1 and figure 7 3 change 2 8 to 33pF part no 0160 2150 A2C9 to 320pF part no 0140 0226 A2C10 to 39pF part no 01400175 A2C11 to 51 pF part no 0160 2201 Change No 3 change the pin connections as follows 7 to 6 13 to 12 16 to 15 15 to 13 Instruments with serial numbers 953 00544 and below had a 03555 66506 Revision A board in them This board is not
30. 71590 1332 obd T1 9100 1458 1 Transformer carrier frequency hp T2 9100 1460 1 Transformer audio hp W1 03555 61616 1 Cable Ass y function hp A2 03555 66509 1 PC Board Ass y range switch hp C1 0121 0128 4 C var 1 4 9 2pF air trim 74970 189 503 5 C2 0160 0196 2 C fxd mica 24pF 5 72136 RDM15C240J3S C3 0160 2130 4 C fxd mica 865pF 1 100 vdcw 72136 RDM15F 865 F1C C4 0121 0128 C var 1 49 2pF air trim 74970 189 503 5 C5 0160 0196 C fxd mica 24pF 5 72136 RDM15C240J3S C6 0160 2130 C fxd mica 865pF 1 100 vdcw 72136 RDM15F 865 F1C C7 0121 0128 C var 1 4 9 2pF air trim 74970 189 503 5 C8 0160 2307 1 C fxd mica 47pF 5 00853 RDM15E470J3C 1 9 0160 3482 1 mica 195 300 vdcw 14655 RDM15F431F3C C10 0160 3586 1 C fxd mica 43pF 300 vdcw 72136 RDM15E4300D3C TC11 0160 3083 1 C fxd mica 62pF 196 500 V 72136 RDM15D620F5C C12 0121 0128 C var 1 4 9 2pF air trim 74970 189 503 5 R1 0698 7330 2 fxd 96 84 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R2 0698 7329 2 fxd met firm 3 266 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R3 0684 2701 2 fxd 27 ohms 41 1096 1 4W 01121 CB2701 R4 0698 7330 fxd 96 84 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R5 0698 7329 fxd met firm 3 266 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd 1 See backdating ir Appendix C 3555 Section Table 6 1 Replaceable Parts Cont d REFERENCE hp TQ DESCRIPTION MFR
31. 75 UNBAL hp 5000 7134 1 Decal pushbutton 135 BAL hp 5000 7135 1 Decal pushbutton 150 BAL hp 5000 7136 2 Decal pushbutton 600 BAL hp 5000 7138 1 Decal pushbutton HOLD hp 5000 7139 1 Decal pushbutton DIAL BAT hp 5000 7140 1 Decal pushbutton NG hp 5000 7147 1 Decal pushbutton 900 BAL hp 8120 1518 1 Cord Set power 70903 obd 6 8 Model 35558 Table 6 1 Replaceable Parts Cont d REFERENCE hp TQ DESCRIPTION MFR MFR PART NO DESIGNATOR PART NO MISCELLANEOUS Cont d 1251 1145 1 Plug battery 72825 7364 525C 49A 2 Handle panel hp 00236 04105 1 Cover battery hp 1390 0186 Stud fastener cadmium plated steel 71286 26542 4 00741 01212 2 Bracket meter hp 03555 00206 1 Panel front hp 03555 00204 1 Panel sub hp 0340 0732 1 Insul Bdg Post hp 03555 26510 1 Test board blank hp 03555 60604 1 Shield Ass y amplifier hp 03555 61204 1 Retainer Ass y cord headphone hp 0355541203 1 Retainer headphone hp 03556 64507 1 Cover assembly hp 03556 64508 1 Case Assembly hp 03556 90007 1 Manual operating and service hp 6 9 6 2 PART NUMBER NATIONAL STOCK NUMBER CROSS REFERENCE INDEX REPLACEMENT NATIONAL NATIONAL STOCK PART TM 11 6625 2779 14 amp P STOCK NUMBER FSCM NUMBER NUMBER 5 NUMBER 1001 CB1041
32. Burgess Battery FUERTES Niagara Falls Ontario Canada Deutsch Fastener Corp Los Angeles Cal Bristol Co The Waterbury Conn Sloan Company Sun Valley Cal ITT Cannon Electric Inc Phoenix Phoenix Arizona National Radio Lab Inc Paramus N J CBS Electronics Semiconductor Operations Div of CBS Inc General Electric Co Mountain View Cal Mountain View Cal Lowell Mass Miniature Lamp Dept Cleveland Ohio Mel Rain Indianapolis Ind Babcock Relays Div Costa Mesa Cal Electronic Enclosures Inc Texas Capacitor Co Tech Ind Inc Atohm Los Angeles Calif Houston Texas RUE Burbank Cal Electro Assemblies Chicago Ill Components Inc Newton Mass Mallory Battery Co of Canada 144 Toronto Ontario Canada Pennsylvania Florocarbon Clifton Heights Penn Burndy Norwalk Conn General Transistor Western Los Angeles Cal Berkeley Carborundum Niagara Falls 6 11 Code No 11236 11237 11242 11312 11314 11453 11534 11711 11717 11870 12136 12361 12574 12697 12728 12859 12881 12930 12954 13019 13061 13103 13327 13396 13835 14099 14193 14298 14433 14493 14655 14674 14752 14960 15106 15203 15287 15291 15558 15566 15631 15772 15801 15818
33. Fischer Special Mfg Cincinnati Ohio General Industries The Elyria Ohio Goshen Stamping amp Tool Co Goshen Ind Electronics Brooklyn N Y Jennings Radio Corp San Jose Cal Groove Pin Corp Ridgefield N J Signalite Inc Neptune J H Winns and Sons Winchester Mass Industrial Condenser 4 Chicago R F Products Division of Amphenol Borg Electronic Corp aM S q wiy Danbury Conn E F Johnson Waseca International Resistance Philadelphia Keystone Carbon Inc St Marys Pa CTS Knights Inc Sandwich Electric Corp Mt Vernon N Y Lenz Electric Mfg Chicago Littlefuse Inc Des Plaines Lord Mfg Erie Pa Marwedel San Francisco Cal General Instrument Corp Micamold Division James Millen Mfg Co Inc J W Miller Los Angeles Cal Cinch Monadnock Div of United Carr Newark N J Fastener Corp San Leandro Cal Mueller Electric Co Cleveland Ohio National Union Newark N J Oak Manufacturing Co The Bendix Corp Electrodynamics Div Crystal Lake N Hollywood Cal Pacific Metals San Francisco Cal Phaostran I
34. HOLD function is not operative on any of the carrier functions 4 6 A variety of INPUT and DIAL jacks are provided which accept Western Electric type 241 and 289 dual plugs 309 310 347 and 358 single plugs dual banana plugs clip leads and bare wires 4 7 BLOCK DIAGRAM DESCRIPTION 4 8 illustrates a simplified block diagram of the Model 3555B Transmission and Noise Measuring BALANCED INPUT FUNCTION SWITCH INPUT sal FUNCTION switch where the input circuitry is set up to accommodate the type of measurement being made For voice frequencies impedances of 900 ohms or 600 ohms can be selected bridged or terminated Voice frequencies are then applied to a transformer with a frequency range of 20Hz to 20kHz The HOLD function places a high inductance bridge across the INPUT terminals to simulate an off hook condition For carrier frequencies impedances of 600 ohms and 135 ohms can be selected terminated or bridged balanced or unbalanced Carrier frequencies at these impedances are applied to a transformer having a frequency range from 5kHz to 600kHz For 75 ohm carrier frequencies an unbalanced input is provided This input can be either terminated or bridged HOLD is not possible on any of the carrier functions 4 10 For longitudinal measurements an Ng function is provided which places a 40dB attenuator across the INPUT terminals The HOLD function bridges the input with a holding coil while measurements are
35. Park Cleveland Ohio 24655 General Radio Co West Concord Mass 24681 Memcor Inc Comp Div Huntington Ind 26365 Gries Reproducer Corp New Rochelle N Y 26462 Grobert File Co of America Inc Carlstadt N J 26851 Compac Hollister Hollister Cal 26992 Hamilton Watch Lancaster Pa 28480 Hewlett Packard Co Palo Alto Cal 28520 Heyman Kenilworth N J 30817 Instrument Specialties Co OC Little Falls N J 33173 Receiving Tube Dept Owensboro Ky 35434 Lectrohm Inc Chicago 36196 Stanwyck Coil Products Lid Hawkesbury Ontario Canada 36291 Cunningham W W amp Hil Dtd cq EID Toronto Ontario Canada 37942 Mallory amp Co Inc Indianapolis Ind 39543 Mechanical Industries Prod Co Akron Ohio 40920 Miniature Precision Bearings Inc Keene N H 40931 Honeywell Inc Minneapolis Minn 42190 Muter Co Chicago Ill 43990 Norgren Co Englewood Colo 44655 Ohmite Mfg Skokie 46384 Penn Eng amp Mfg Corp Doylestown Pa 41904 Polaroid Corp Cambridge Mass 48620 Precision Thermometer amp Inst 4 99 y Southampton Pa 49956 Microwave amp Power Tube Div Waltham Mass 52090 Rowan Controller Westminster Md 52983 HP Co Med Elec Div Waltham Ma
36. San Fernando Elec Mig San Fernando Cal Thomson Ind Inc Long Island N Y Industrial Retaining Ring Co Irvington N J Automatic amp Precision Mfg Englewood N J Reon Resistor Corp Yonkers N Y Litton System Inc Adler Westrex Freeport Commun Div New Rochelle N Y R Tronics Inc Jamaica N Y Rubber Teck Inc Gardena Cal Hewlett Packard Co Medical Elec Div Pasadena Cal Microdot Inc So Pasadena Sealectro Corp Mamaronech N Y Zero Burbank Cal Inc SA pare Cleveland Ohio General Mills Inc Electronics Div We Rhett Minneapolis Division Hewlett Packard Palo Alto Cal North Hills Electronics Inc Glen Cove N Y International Electronic Research Corp a pn Burbank Cal Columbia Technical Corp New York N Y Varian Associates Palo Alto Cal Atlee Corp Winchester Mass Marshall Ind Capacitor Div Monrovia Cal Control Switch Division Controls Co of America El Segundo Cal Delevan Electronics Corp East Aurora N Y Wilco Corporation Indianapolis Ind Branson Corp Whippany N J Rembrandt Boston Mass Hoffman Electronics Corp Semiconductor Division Technol
37. Section V RESPONSE DAMP Set the 654A 600 BAL output level to 0dBm at a frequency 20Hz The 35558 meter should Becaorr 0 1SdBm 0 3dBm Note this indication Change the 654A output level to 70dBm at a frequency of 20Hz Change the 3555B RANGE switch to 70dBm and change the FUNCTION to VF Nm 600 BAL The 3555B meter should indicate OdBm 0 3dBm Note the exact indication Compensation should be made between the 900 BAL OdBm check step c the 600 BAL 70dBm check step d To raise the level increase the value 72 until the 900 BAL check indicates high by the same amount that the 600 BAL 70dBm check indicates low The total difference should not exceed 0 3dBm COMMON MODE ADJUSTMENT a Connect the equipment as shown ir Figure 5 5 and set the 3555B controls as follows FUNCTION VF Nm 600 BAL dS TMS TERM RANGE tct Set the 654A frequency to 20kHz and adjust the output level of the 654A for OdBm indication on the 35558 meter Disconnect the left output terminal on the 654A and short the tip and ring together on the cable Down range the 3555B RANGE switch for an on scale indication Adjust A1C7 for minimum indication on the 3555B meter This indication must be down at least 60 dB Change the 3555B FUNCTION switch to CARRIER 600 BAL and change the 654 frequency to 100kHz Use the procedure described abov
38. The battery test operates on internal battery office battery or ac power source Select either NOISE TERM or NOISE BRDG depending on the measurement being made Select the impedance to match the circuit to be tested using the FUNCTION pushbuttons The 900 BAL VF Nm pushbuttons only should be used for noise metallic measurements in the frequency range of 20Hz to 20kHz The HOLD function can be used in NOISE TERM if desired Select the appropriate weighting filters using the NOISE WTG switch Set the RANGE switch to 110dBrn Connect the set to the circuit to be tested using a suitable patch cord and down range for an on scale indication Observe the meter fluctuations for two or three minutes and take a reading where the meter pointer appears to be most of the time disregarding any occasional peaks NOTE For rapidly fluctuating noises such as atmospheric noise or switching noise operate the RESPONSE switch to DAMP and read the level of the most frequently occurring peaks Noise level is equal to the sum of the blue RANGE switch setting in dBrn and the indication on the blue meter scale in dBrn EXAMPLE RANGE 40dBrn METER 5dBrn NOISE LEVEL 45dBrn Section 3555 Table 3 6 Balance STEP PROCEDURE Table 3 5 Noise to Ground Measurements STEP PROCEDURE Turn the 3555B POWER switch to ON and depress the DIAL BAT pushbutton The meter should indicate in the green BAT GOO
39. actual input level to the set as Section indicated on the recorder will be the algebraic sum of the RANGE 3 28 NOISE MEASUREMENT 3 29 One of the primary functions of this set is to measure message circuit noise both metallic and noise to ground The weighting filters built into this set are switch selected and their characteristics conform to the standards set up by the Bell System and Edison Electric Institute 3 30 In general noise metallic measurements are made by connecting the circuit under test to the INPUT jacks with a suitable patch cord selecting the proper bridging or terminate condition and impedance selecting the proper weighting filter and operating the RANGE switch to provide an on scale meter indication Noise measurements involve many of the same_operations as the level measurements discussed parece S llana only the differences will be discussed 3 31 Four filters are supplied for noise measurements C MESSAGE and 3kHz FLAT for message circuit noise measurement a PROG and 15kHz FLAT for broadcast studio transmitter links and telephone company program circuits These filters are necessary to allow the measuring set to approximate the response of the human ear and give an indication representative of a person s subjectiveness to noise The frequency response of these filters is shown Figures 4 5 4 6 3 32 Once a circuit has been connected the RANGE switch is adjusted until the noise fluctuat
40. amplifier 18 and A3Q19 The output of the differential amplifier is amplified by 20 and applied to 21 which controls the conduction of the series transistor 022 The output of this series regulator is held at 20 volts 1 volt The maximum ac ripple and noise on the output voltage is 200uV rms 4 40 It should be noted that when operating the set from either the battery or from an ac source capacitor C2 will always be charged whether the set is turned on or not Caution should be exercised when servicing the power supply 3555 Section V SECTION V MAINTENANCE 5 1 INTROOUCTION can be substituted provided they meet the required 5 2 This section of the manual contains information specifications necessary in the maintenance of the hp Model 3555B Transmission and Noise Measuring Set Included are performance checks adjustment calibration procedures and troubleshooting 5 3 The test equipment needed to properly maintain and service the Model 3555B is listed in Table 5 1 Included Table 5 1 jis the equipment to be used required specifications and recommended model If the recommended model is not available other equipments 5 4 FACTORY SELECTED VALUES 5 5 Factory selected values are denoted on the schematic diagrams by an asterisk The nominal value is shown The value in your instrument may be different or the part may be omitted 5 6 150 BAL CONVERSION a To convert
41. and maintain this equipment The manual was not prepared in accordance with military specifications therefore the format has not been structured to consider categories of maintenance Para Page SECTION 0 INTRODUCTION SCOPE CE O Indexes of Publications Maintenance forms records and 0 Administrative 5 0 Destruction of Army electronics materiel ene 0 Reporting of equipment improvements recommendations Items comprising an operable equipment 22000 10000 m GENERAL INFORMATION api rore 1 Accessory equipment 1 Instrument identification U 150 BAL INSTALLATION 2 Waranty exception ME 2 Power 2 Three conductor power 2 sss a sasa Ut MI MILI Installation and removal of 2 CoverrTemoVdl eit conr Ce iiu Itu i Repackaging for 5 OPERATING INSTRUCTIONS Mint OU CLG Wass oie Er 3 Controls connectors
42. applied to the first in a series of amplifiers The first amplifier consists of A4Q1 through A4Q4 Differential amplifier A4Q1 and A4Q2 amplifies the signal and applies it to A4Q3 and A4Q4 The emitter circuit A4Q4 provides two feedback signals positive feedback through A4R8 and A4C4 to the base of A4Q1 and negative feedback to the base of A4Q2 The gain of this amplifier is controlled by the ratio of the value of A4R10 to the value of A4R9 For example increasing the value of A4R9 would increase the negative feedback and reduce the amplifier gain Gain can be calculated by the equation A4R10 Gain 1 A4R9 Positive feedback to the base of A4Q1 determines the frequency response of this amplifier and is controlled by the value of A4C4 and A4R8 All five of the amplifiers are used in C Message weighting 4 28 The Program weighting filter utilizes amplifiers No 2 and No 3 as shown in Figure 7 11 These amplifiers are identical to the one described in the preceeding paragraph except for the value of the positive feedback utilized for shaping and the negative feedback used for gain control This negative feedback is modified by resistance in the feedback divider at the base of 4012 Transistors A4Q5 406 provide additional gain required for Program weighting Potentiometer A4R3B is used for PROG level adjustment at 1kHz Section IV 4 29 3kHz FLAT 15kHz FLAT weighting filters utilize only amplifier as
43. be encountered the low ranges particularly if other instruments are connected in any way to the 3555B In order to eliminate this problem operate the set from its own internal battery or use the C MSG filter If the C MSG filter is used perform the filter calibration described in Paragraph 5 24 then perform the following step e Change the 654A to 80dBm output level at 1 00kHz Change the 3555B RANGE switch to 80dBm Adjust 26 for 0dBm indication on the 3555B meter Change the 654A to 135 BAL 150 BAL and change the 3555B FUNCTION to 135 BAL 150 BAL Adjust A3R24 for OdBm indication on the 3555B meter Change the 3555B RANGE switch to 5OdBm INPUT switch to TMS TERM and the FUNCTION switch to VF Nm 600 BAL Change the 654A to 1kHz at an output level of 50dBm 600 BAL Adjust the AMPLITUDE control for exactly OdBm indication on the 3555B meter Change the 3555B FUNCTION switch to 900 BAL without changing anything else Adjust A3R20 for 0 15dBm indication on the 3555B meter FREQUENCY RESPONSE ADJUSTMENT a The following adjustment consists of selecting fixed values for frequency compensation at 20Hz 600 BAL 70dBm and 20kHz 600 BAL 70dBm Connect the 654A 600 BAL output to the 3555B input Set the 3555B controls as follows FUNCTION VF Nm 900 BAL 5 RANGE OdBm 5 9 5 22 5 23
44. between tip and ring and 200 volts rms at 60Hz between either tip or ring and ground 3 26 The switch marked RESPONSE determines the speed of the meter response and is usually left in the NORM position for transmission measurements 3 27 The jack marked DC MON accepts a Western Electric 310 or 347 plug with connections to the tip and sleeve The dc voltage supplied by this jack can be used to operate a dc potentiometric recorder requiring 1V or a dc galvanometric recorder requiring 500uA The dc output is proportional to input level on any one range and not meter deflection since the meter is logarithmically scaled Knowing the current required to drive the recorder full scale and the input impedance of the recorder enter these numbers into the recorder compatability Figure 3 4 to determine if the recorder is suitable for use with this set If these numbers do not fall within the compatability area refer to Paragraph 3 41 Connect an input voltage to the set and adjust the RANGE switch until a near full scale indication is observed on the meter Connect the recorder plug with the tip negative to the DC MON jack and adjust the input level until the meter indicates Mark this point which should be near full scale on the recorder paper Decrease the input level until the meter indicates 1dBm Mark this point on the recorder paper Continue until the recorder has been calibrated for each major dBm division on the meter The
45. indicated in 7 1 The only difference between these two active filters is in the positive feedback used for shaping and in the negative feedback used for gain The negative feedback is altered by adding resistance to the feedback divider at the base of A4Q12 4 30 METER AMPLIFIER Schematic No 4 4 31 The meter amplifier consists A3Q6 through A3Q10 The signal is first amplified by differential amplifier A3Q6 and A3Q7 The signal is taken from the collector of A3Q6 and then amplified by A3Q9 and A3Q10 Transistor A3Q8 provides isolation between A3Q7 and A3Q9 to prevent undesired feedback Two signals are taken from A3Q10 The collector circuit supplies a signal to the DIAL AC MON jacks for the purpose of listening to the measured signal The emitter circuit of A2Q10 provides a drive signal for the detector circuit 4 32 DETECTOR Schematic No 4 4 33 The detector is a class B rms detector which combines the features of an average detector and a peak detector When the average detected signals and the peak detected signals are combined in the proper proportion an equivalent rms response is produced 4 34 First consider the average detection in this circuit Sed Figure 7 5 Transistors 12 13 and 15 16 are functionally symmetrical This means that A3Q14 and A3Q17 are driven by the same signal When the signal at the base of A3017 and 14 goes negative A3Q 4 turns on and 17 tu
46. interchangeable with the Revision B board The above pin connections are for the Revision A board Change No 4 Delete S6 figure 7 5 in Table 6 1 Earlier instruments did not have this switch See the following figure for earlier instruments C 1 Model 35558 Change part the case assembly to 03555 04505 hange cover part no to 03555 04504 Table 6 1 Change the part no of the power cord to 81 20 0249 Change the part no of the power connector J1 to 1251 0148 Fi 230v AC es Change 5 Table 6 1 Change to the following gray parts Cover battery 00236 04104 Bracket meter 00741 0 1209 Panel front 03555 00203 Assy cover 03555 64504 Assy case 03555 64506 Knob pushbutton 0370 0440 Change No 6 Change C2 to 0180 0110 8 uF Delete CR2 4 1901 0025 Change T1 part no to 9100 1457 Delete CR2 4 from the Power Supply Rectifier Change No 7 Delete CR6 1901 0040 Delete CR6 across M1 U S GOVERNMENT PRINTING OFFICE 1980 603 128 66 C 2 Order the Secretary the Army E C MEYER General United States Army Official Chief of Staff J C PENNINGTON Major General United States Army The Adjutant General DISTRIBUTION Active Army HISA Ft Monmouth 21 USAICS 3 USAINSCOM 2 MAAG 1 COE 1 USARMIS 1 1 USAERDAA 1 USAARENBD 1 USAERDAW 1 1 Ft C
47. provide the necessary gain at all impedances This amplifier is normalized at 600 ohms and the following discussion is for the 600 ohm function 4 22 Diodes A3CR1 thru A3CR4 serve as protection for the input amplifier Signals greater than 7 volts peak to peak will be conducted to ground through these diodes The gain of this amplifier is determined by the negative feedback from the emitter of A3Q5 to the base of 2 This feedback is first determined by the ratio of to the sum of 14 and 15 In position 1 of the RANGE switch 80DBM this feedback is further divided by the ratio of A3R11 to the sum of A3R25 and A3R26 position 2 700 of the RANGE switch the feedback is determined by the ratio of 11 to the sum of A2R13 25 and A3R26 In position 3 60DBM of the switch the feedback is determined by the ratio of to the sum of A2R13 A2R14 25 and 26 Section Model 3555 Table 4 1 Range Attenuation and Amplifier Gain 30dBm 20dBm 10dBm 10dBm 20dBm 30dBm 40dBm 50dBm 60dBm 70dBm 80dBm In positions 4 thru 12 SODBM thru 30DBM A3R11 is bypassed for maximum feedback The gain of the amplifier in these nine positions is a constant 2 5dB Potentiometer 26 is for calibration of the 80DBM range 600 ohm function Resistor A3R27 is used to maintain a charge on A3C22 to prevent transients when changing ranges 4 23 In order th
48. shield must be removed To do this remove the two screws on each side of the set and lift out the shield h To reassembly the set use the reverse of the procedure described above 5 27 TROUBLESHOOTING PROCEDURES 5 28 following information is supplied to assist in locating a malfunction in the set in a minimum of time It should first be determined that a malfunction does indeed exist and that the trouble is not external to the set 5 29 Before starting to troubleshoot the set use the front panel controls to determine exactly which function if any is operating properly Table 5 6 can aid you in this analysis In many cases a good front panel analysis of the symptoms can lead you directly to the trouble 5 30 simplify troubleshooting the following information is supplied a Troubleshooting Tree The troubleshooting tree is based on the half split method of troubleshooting a set The trouble can be isolated to a general area or block using this tree Once the trouble has been isolated to an area a reference is given to a paragraph where more specific information can be found b Functional Block Diagram The functional block diagram can also be used to isolate the trouble to block The diagram contains all of the essential blocks that make up the set and includes voltage levels test points and adjustments The troubleshooting tree and functional block diagram are keyed together by the numbers with a ci
49. step procedures for measuring levels and noise balance recorder calibration and transmission loss using the 3555B For a more detailed discussion on level and noise measurements refer to paragraphs 3 12 through 3 69 150 BAL CONVERSION 3 12 3 70 The 3555B comes equipped with all the necessary parts for converting the 135 BAL function to a 150 BAL function following is a simplified procedure for making the modification a Remove the set from the case and remove the FUNCTION board Clip the shorting wire from across A1R17 sed Figure 7 2 and reinstall the FUNCTION board Leave the set out of the case b Set the 3555B controls as follows RANGES n A OdBm FUNGI ION nies 135 BAL INPUT trees 5 Remove the 150 BAL decal from the envelope supplied with the set Remove the backing from the decal and place it over the 135 BAL function pushbutton d Connect a 150 ohm balanced source to the input of the 35558 at a level of OdBm 387 rms at a frequency of 1kHz Turn the 3555B ON and adjust 24 3 0dBm indication on the 35558 meter e Reinstall the set in its case 3555 Section Table 3 4 Noise Metallic Measurements STEP PROCEDURE STEP PROCEDURE Table 3 3 Level Measurement the 3555B ON and depress the DIAL BAT pushbutton The meter should indicate in the green BAT GOOD area f it does not replace the battery or check the pow
50. the maximum of the frequently occurring peaks disregarding the occasional high peaks The meter indication in dBm is equal to VU volume units Model 3555B 3 40 Crosstalk measurements involve low level measurements and part of the meter indication may be 3 8 Model 3555B caused by noise in addition to crosstalk The general technique is to measure with crosstalk and noise present and then measure noise alone A correction factor must then be applied and can be found in Table 3 2 3 41 RECORDER COMPATIBILITY 3 42 If an external recorder is to be used to monitor the dc output of the 3555B the Recorder Compatibility graph Figure 3 4 should be consulted to determine if your particular recorder can be used Recorders with input characteristics that fall below the compatibility area can be used provided a suitable resistor is used between the 3555B dc output and the recorder input 9 43 To choose the value of this resistance simply follow the line designating the full scale current of your recorder horizontally until it intersects the top line in the Recorder Compatibility graph From this intersection follow the vertical line to find the total impedance RT required for full scale deflection see The input impedance of the recorder should be subtracted from this value RT to determine the value of R1 For example assume that your particular recorder has an input impedance of 2000 ohms with a full scale sensitivity of 20uA Follow the
51. 1 10 32 obd R7 0757 0290 1 fxd met flm 6 19 kilohms 1 1 8 14674 C4 obd R8 0698 3158 fxd met flm 23 7 kilohms 1 1 8W 91637 MF 1 10 32 obd R9 0698 3245 1 fxd 20 5 kilohms 1 1 8W 14674 Cr obd R10 0757 0455 1 fxd met flm 36 5 kilohms 1 1 8W 14674 C4 obd R11 0698 4434 1 fxd met firm 2 32 kilohms 1 1 8 91637 CMF 1 10 32 obd 51 3100 1794 1 Switch lever input 76854 1332 obd 52 03555 61904 1 Switch Ass y weighting hp 53 3101 0045 1 Switch slide 82389 11 1014 54 55 3101 0001 2 Switch toggle SPST 04009 80994 HB 56 3101 1234 1 Switch slide 82389 11 1242 T1 9100 1457 1 Transformer power hp W1 03555 69503 1 Cable Ass y hp 03555 69504 1 Cable Ass y hp 03555 69502 1 Cable Ass y W4 03555 69505 1 Cable Ass y hp W5 Not assigned W6 03555 69501 1 Cable Ass y hp W7 03555 61611 1 Cable Ass y interconnecting and range hp MISCELLANEOUS 0340 0099 4 Insulator binding post hp 0340 0100 2 Insulator binding post single hp 0370 0035 1 Knob bar w arrow black hp 0370 0046 2 Knob lever switch black hp 0370 0440 8 Knob pushbuttons grey hp 1390 0137 4 Washer retaining 1 4 turn fastener 71286 2600 1W 1390 0186 4 Stud 1 4 turn fastener 71286 265424 1400 0062 1 Clip cable 78553 C21891 017 24 1400 0076 2 Clip fuse 75915 101002 1520 0001 1 Wafer cap plate mtg 4 lug 56137 Grade X 831 4040 0476 1 Insulator jack hp 5000 7126 1 Decal pushbutton
52. 10 1 4 01121 1011 18 0684 1041 1 comp 100 kilohms 10 1 4 01121 1041 19 0698 3154 1 fxd met flm 4 22 kilohms 1 1 8W 91637 MF 1 10 32 obd R20 2100 2829 R var carbon comp 5 kilohms 30 71590 Type E8 83716 R21 0698 3155 1 fxd metflm 4 64 kilohms 1 1 8W 91637 MF 1 10 32 obd R22 0698 4405 1 fxd met flm 107 ohms 1 1i8W 14674 C4 obd R23 0684 2221 1 fxd comp 2200 ohms 10 1 4 01121 CB2221 R24 2100 2829 R var carbon comp 500 ohms 30 71590 Type E8 83716 R25 0698 4014 1 R fxd met flm 787 ohms 1 1 8W 14674 C4 obd R26 2100 2829 R var carbon comp 500 ohms 30 71590 Type E883716 R27 0698 4521 fxd met flm 154 kilohms 1 1 8W 14674 C4 obd R28 R29 Not assigned R30 0684 3341 1 R fxd comp 330 kilohms 10 1 4W 01121 CB3341 R31 0684 1541 3 fxd comp 150 kilohms 10 1 4W 01121 CB1541 R32 0684 1011 R fxd comp 100 ohms 10 1 4W 01121 CB1011 R33 0684 1221 fxd comp 1 2 kilohms 10 1 4W 01121 CB1221 R34 0684 1021 6 R fxd comp 10000 ohms 10 1 4W 01121 C81021 R35 R36 0684 1541 R fxd comp 150 kilohms 10 1 4W 01121 CB1541 R37 0684 4721 R fxd comp 4700 ohms 10 114W 01121 C84721 R38 0698 4454 1 R fxd met flm 523 ohms 1 1 8W 91637 MF 1 10 32 obd R39 0684 3921 3 R fxd comp 3900 ohms 10 1 4W 01121 CB3921 6 4 3555 Section Table 6 1 Replaceable Parts Cont d REFERENCE hp TQ DESCRIPTION MFR MFR P
53. 16037 16179 16352 16554 16585 16688 16758 17109 17414 17675 17745 17856 17870 18042 18083 18324 18476 18486 18565 18583 18612 18873 18911 19315 19500 19589 Manufacturer Address CTS of Berne Inc Chicago Telephone of California So Pasadena Cal Bay State Electronics Corp Waltham Mass Teledyne Inc Microwave Div eese Palo Alto Cal National Seal Downey 1 Precision Connector Corp Jamaica Y Duncan Electronics Inc Costa Mesa Cal General Instrument Corp Semiconductor Division Products Group Newark N J Imperial Electronic Inc Buena Park Cal Melabs Inc Palo Alto Cal Philadelphia Handle Co Camden Grove Mfg Co Inc Shady Grove Pa Gulton Ind Inc Data Div YR Albuquerque N M Clarostat Mig Co Dos Work pone Dover N H Elmar Filter w Haven Conn Nippon Electric Co Ltd Tokyo Japan Metex Electronics Clark N J Delta Semiconductor Inc Newport Beach Cal Dickson Electronics Corp Scottsdale Arizona Airco Supply Co Inc Witchita Kansas Wilco Products Detroit Mich Thermolloy Dallas Texas Solitron Devices Inc N Y Telefunken GmbH Hanover Germany Midland Wright Div of Pacific Industries Inc
54. 2 C15 0180 0228 C fxd elect 22uF 10 15 vdcw 37942 TAS226K015P1C C16 0180 0393 3 C fxd elect 39uF 10 10 vdcw 37942 TAS396KO10PIC C17 0160 2964 fxd cer 0 01uF 80 20 25 vdcw 72982 5835000 Y5U0 1032 C18 Not assigned C19 0180 0197 C fxd 2 2uF 10 20 vdcw 56289 150D225X9020A2 DYS C20 0160 0763 C fxd mica 5pF 10 72136 RDM15C050K5SS C21 0180 1702 1 C fxd Ta elect 180uF 20 6 vdcw 37942 obd C22 0160 2964 C fxd cer 0 01uF 80 20 25 vdcw 72982 5835 000 Y5U0 1032 C23 0180 0197 fxd 2 2uF 10 20 vdcw 56289 150D225X9020A2 DYS C24 0180 0137 1 C fxd Ta 100uF 20 10 vdcw 56289 150D107X0010R2 DYS C25 0180 0197 C fxd 2 2uF 10 20 vdcw 56289 150D225X9020A2 DYS C26 0150 001 1 1 C fxd TiO2 1 5pF 20 500 vdcw 78488 Type GA obd C27 0180 0393 C fxd elect 39uF 10 10 vdcw 37942 TAS396KO10P1C C28 0180 0196 1 fxd 56uF 10 15 37942 TAS566K015P F C29 0180 0374 1 fxd Ta elect 1OuF 10 20 vdcw 37942 5106 020 1 C30 thru C32 0180 0228 C fxd Ta elect 22uF 10 15 vdcw 37942 5226 015 C33 0180 0197 C Ta 2 2uF 10 20 vdcw 56289 150D225X9020A2 DYS C34 0180 1794 1 C Ta elect 22uF 10 35 vdcw 56289 150D226X9035R2 DYS C35 thru C37 0180 1746 fxd Ta elect 15uF 10 20 vdcw 56289 150D156X9020B2 DYS CR1 CR2 1901 0376 2 Diode Si 35 wiv 2pF 07933 RD5288 CR3 CR4 1902 3030 4 Diode zener 3 01V 5 400mW 20mA 04713 5210939 32 5 thr
55. 32 obd R18 0757 0443 1 fxd met flm 11 kilohms 1 1 8W 14674 C4 obd R19 Not assigned R20 0698 7375 R fxd met flm 28 640 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R21 A B C 1810 0027 carbon flm network 2X100K 10 kilohms 10 56289 178C5 R22 07570451 1 fxd met 24 3 kilohms 1 1 8W 14674 C4 obd R23 0757 0450 fxd met flm 22 1 kilohms 1 1 8W 75042 CEA obd R24 0698 0043 fxd met 20 kilohms 4 1 1 8W 91637 CMF 1 10 32 obd R25 0638 1407 1 fxd met flm 44 2 kilohms 1 1 8W 14674 C4 obd R26 A B C 1810 0027 carbon flm network 2X100K 10 kilohms 10 56289 178C5 R27 0698 7365 1 fxd me flm 13 394 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R28 0038 6043 fxd met flm 20 kilohms 4 1 91637 CMF 1 1032 obd R29 0757 0465 1 fxd met 100 kilohms 1 1 8W 14674 C4 obd R30 R31 0684 1051 3 R fxd comp 1 megohm 10 1 4W 01121 C81051 R32 0757 0280 2 fxd met flm 1 kilohm 1 1 8W 91637 CMF 1 10 32 obd R33 0757 0442 fxd met flm 10 kilohm 1 1 8W 91637 MF 1 10 32 obd R34 0757 0448 1 R fxd met flm 1 amp 2 kilohms 1 1 8W 91637 MF 1 10 32 obd R35 R36 0757 0472 R fxd met flm 200 kilohms 1 1 8W 75042 CEA obd R37 R38 0698 7366 2 fxd met flm 109 64 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R39 A B C 1810 0027 R carbon flm network 2X100K 10 kilohms 10 56289 178C5 R40 0638 0043 R fxd met flm 20 kilohm 1 91637 CMF 1 10 32 obd R41 0698 7367 1 fxd met flm 78 028 kilohms 0 1
56. 5 8M coe ATSIPF 1 700 PF R27 3 39 0 mo Ras 36 50 D 20K 1758K HEU 4Q c ee WIRE DESTINATIONS 20 SCHEMATIC NUMBER NUMBER LOCATOR AMPLIFIER DETECTOR 8 SERIES REGULATOR ASSEMBLY 03555 66508 F METER AMPLIFIER DETECTOR 0 DIAL AC MON 5 lt H lt 62 04 v SECOND APPEARANCE res SCHEMATIC 1 750 CAL C20 Ek 2 FROM i R35 9 WEIGHTING FILTERS NOISE 3 R38 INPUT SWITCH OUTPUT TMS 1 5 THRU 1 L C6 RIO 71 RESPONSE 2320 815 C7 E top 2854 R55 48 cso 06 2089 Re2 29 CRIA 9 LI R24 POWER m A3 s di a 20 A 10 hp Part No 03555 66508 fing lt 1 lt i 1 wor 20v ARO POER Str
57. 6 RDM19F172F1S C19 0180 0228 fxd Ta elect 22uF 10 15 vdcw 37942 TAS226KO15P1C 20 21 0180 0291 C fxd Ta elect 1uF 10 35 56289 15OD105X9035A2 DYS C22 Not assigned C23 0180 0197 C Ta 2 2uF 10 20 vdcw 56289 150D225X9020A2 DYS C24 0140 0163 C fxd mica 4751pF 1 300 vdcw 72136 RDM20F 4751 F3S C25 0140 0203 C mice 30pF 1 5 72136 RDM15F421F3G C26 0140 0163 C 4751 1 300 vdcw 72136 RDM20F 4751 F3S C27 0180 0228 fxd Ta elect 22uF 10 15 37942 TAS226K01SPIG C28 C29 0140 0163 C fxd mica 4751pF 1 300 vdcw 72136 RDM20F 4751 F3S C30 0140 0203 C fxd mice 30pF 5 72136 RDM15F421F3G 6 5 Section VI Model 3555B Table 6 1 Replaceable Parts Cont d REFERENCE hp TQ DESCRIPTION MFR MFR PART NO DESIGNATOR PART NO A4 Cont d C31 0180 0228 fxd Ta elect 22uF 10 15 37942 TAS226K015P1C C32 0180 0291 C elect 1uF 10 35 vdcw 56289 150D105X9035A2 DYS C33 0180 0387 1 C fxd Ta elect 47uF 5 20 vdcw 37942 TAS476J020P1F thru CR5 1901 0026 Diode Si 100 wiv 12pF 100mA 24446 55410 01 02 1854 0071 16 TSTR Si NPN 2N3391 01296 SKA1124 Q3 1853 0086 6 TSTR Si PNP 2N5087 04713 SPS 3322 Q4 Q5 1854 0071 TSTR Si NPN 2N3391 01296 SKA1124 Q6 1853 0086 TSTR Si PNP 2N5087 04713 SPS 3322 Q7 Q8 1854 0071 TSTR Si NPN 2N3391 01296 SKA1124 09 1853 0086 TSTR Si 2 5087 04713 SPS 3322 010 thru Q12 1854 0071 TSTR
58. 81349 81349 81349 81349 81349 81349 81349 49956 81349 GAO 47PFPORM5PCT 78488 JAN1N821 192P10452 78PCG5 81349 56289 02660 5905 00 107 0656 5905 00 110 0388 5905 00 114 5339 5905 00 115 7953 5905 00 135 3973 5905 00 105 7764 5905 00 141 0743 5905 00 141 0717 5905 00 110 7622 5905 00 119 8768 5905 00 104 8358 5920 00 661 0530 5935 00 192 4826 5961 00 222 6128 5910 00 192 7180 5910 00 834 9437 5961 00 866 5454 5910 00 984 2845 5935 00 919 6391 cos Manufacturer Address 00000 U S A Any supplier of U S 00136 McCoy Electronics Mount Holly Springs 00213 Sage Electronics Rochester 00287 Inc Danielson Conn 00334 Humidial Colton Calif 00348 Valley Stream N Y 00373 Garlock Inc Cherry Hill N J 00656 Aerovox Bedford Mass 00779 Amp Inc Harrisburg 00781 Aircraft Radio Corp Boonton N J 00809 Croven Ltd Whitby Ontario Canada 00815 Northern Engineering Laboratories Burlington Wis 00853 Sangamo Electric Co Pickens Div Pickens S C 00866 Goe Engineering City of Industry Cal 00891 E Holmes Corp Los Angeles Cal 00929 Microlab Livingston N J 01002 General Electric Co Capacitor
59. 853 0036 TSTR Si PNP 2N3906 04713 SPS 3612 Q13 1854 0092 2 TSTR NPN 2N3563 04713 MPS 3563 Q14 1853 0049 2 TSTR Si PNP 04713 hp Q15 1854 0215 TSTR Si NPN 2N3904 04713 SPS 3611 Q16 1853 4049 TSTR Si PNP 04713 hp Q17 1854 0401 1 TSTR NPN 04713 hp Q18 Q19 1853 0235 3 TSTR Si PNP 2N3547 12040 NS62048 Q20 1854 0022 1 TSTR NPN 01295 591294 Q21 1853 0235 TSTR Si PNP 2N3547 12040 NS62048 Q22 1853 0037 1 TSTR Si PNP 04713 2N2904A R1 0757 0334 1 R fxd met fIm 301 ohms 1 1 4W 91637 MF 1 8 44 obd R2 0698 4521 2 R fxd met fIm 154 kilohms 1 1 8W 14674 0698 4533 1 fxd met 294 kilohms 1 1 8W 14674 C4 obd R4 0684 4731 2 fxd comp 47 kilohms 10 1 4 01121 CB4731 R5 0684 1221 2 fxd comp 1 2 kilohms 10 1 4W 01121 CB1221 R6 0684 1011 5 R fxd comp 100 ohms 10 1 4W 01121 CB1011 R7 R8 0684 2241 2 R fxd comp 220 kilohms 10 1 4W 01121 C82241 R9 0684 4721 3 fxd comp 4700 ohms 10 1 4 01121 CB4721 R10 0684 1011 fxd comp 100 ohms 10 1 4W 01121 CB1011 R11 0698 7375 3 fxd met flm 28 64 kilohms 0 1 1 8W 91637 CMF 1 10 32 obd R12 0684 1011 fxd comp 100 ohms 10 1 4W 01121 CB1011 R13 R14 0757 0273 2 fxd met flm 3 01 kilohms 1 1 8W 91637 MF 1 10 32 obd R15 2100 2829 1 var carbon comp 500 ohms 30 1 4W 4 71590 8 83716 16 0698 4458 1 fxd met 590 ohms 1 1 8W 14674 17 0684 1011 fxd comp 100 ohms
60. ANCE ALLOCATION Section INTRODUCTION B 1 General This appendix provides a summary of the maintenance operations for TA 885 U It authorizes categories of maintenance for specific maintenance functions on repairable items and components and the tools and equipment required to perform each function This appendix may be used as an aid in planning maintenance operations B 2 Maintenance Function Maintenance function will be limited to and defined as follows Inspect To determine the serviceability of an item by comparing its physical mechanical and or electrical characteristics with established standards through examination b To verify serviceability and to detect incipient failure by measuring the mechanical or electrical characteristics of item and comparing those characteristics with prescribed standards c Service Operations required periodically to keep an item in proper operating condition i e to clean decontaminate to preserve to drain to paint or to replenish fuel lubricants hydraulic fluids or compressed air supplies d Adjust To maintain within prescribed limits by bringing into proper or exact position or by setting the operating characteristics to the specified parameters e Align To adjust specified variable elements of an item to bring about optimum or desired performance f Calibrate To determine and cause corrections to be made or to be adjusted on instruments or test m
61. ART NO DESIGNATOR PART NO Cont d R40 0684 4721 fxd comp 4700 ohms 10 1 4 01121 CB4721 R41 R42 0698 3382 2 R fxd met flm 5 49 kilohms 1 1 8W 91637 MF 1 10 32 obd R43 2100 1770 1 R var ww 00 ohm 100 1 2W trimmer 80294 3 365P E88 101 R44 0698 3223 1 R fxd met flm 1 24 kilohms 1 1 8W 91637 MF 1 10 32 obd R45 0684 2231 3 fxd comp 22 kilohms 10 1 4 01121 CB2231 R46 0684 3921 R fxd comp 3900 ohms 10 1 4W 01121 CB3921 R47 0684 8211 2 R fxd comp 820 ohms 10 1 4W 01121 CB8211 R48 0684 2231 fxd comp 22 kilohms 10 1 4 01121 CB2231 R49 0757 4442 3 R fxd met flm 10 kilohms 1 1 8W 91637 MF 1 10 32 obd R50 0684 1031 2 fxd comp 10 kilohm 10 1 4W 01121 CB1031 R51 0084 8211 fxd comp 820 ohm 10 1 4W 01121 CB8211 R52 0767 0280 fxd met flm 1 kilohm 1 1 8W 91637 CMF 1 10 32 obd R53 R54 0684 1211 2 fxd comp 120 ohm 10 1 4W 01121 CB1211 R55 0757 0442 fxd met 10 kilohms 1 1 8W 91637 MF 1 10 32 obd R56 thru R58 Not assigned R59 0757 4468 1 fxd met 130 kilohm 1 1 8W 14674 C4 obd R60 0684 3331 1 fxd comp 33 kilohms 106 1 4W 01121 CB3331 R61 0684 1001 3 fxd comp 10 ohm 100 1 4W 01121 CB1001 R62 0684 3921 R fxd comp 3900 ohms 10 1 4W 01121 CB3921 R63 0684 1031 fxd comp 10 kilohms 100 1 4W 01121 CB1031 R64 0684 2231 fxd comp 22 kilohms 10 1 4W 01121 CB2231 R65 thru R67 0684 1021 R fxd comp 1000 ohms 10 1 4W 01121 CB1021
62. Bm Range OdBm Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range 10dBm 0 5dBm 0dBm 0 5dBm 10dBm 0 5dBm 20dBm 0 5dBm 30dBm 0 5dBm 40dBm 0 5dBm 50dBm 0 5dBm 10dBm 0 2dBm 0 2dBm 10dBm 0 2dBm 20dBm 0 2dBm 30dBm 0 2dBm 40dBm 0 2dBm 50dBm 0 2dBm VF Nm 600 BAL and 900 BAL LEVEL ACCURACY CHECK 20Hz to 20kHz OdBm Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range 60dBm Range 70dBm Range 80dBm Range 40Hz to 1SkHz OdBm Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range 60dBm Range 100Hz to 20kHz 30dBm Range 20dBm Range 10dBm Range 100Hz to 15kHz 30dBm Range 20dBm Range 10dBm Range 600 ohms 2 900 ohms 0 5dBm 10dBm 0 5dBm 20dBm 0 5dBm 30dBm 0 5dBm 40dBm 0 5dBm 50dBm 0 5dBm 60dBm 0 5dBm 70dBm 0 5dBm 80dBm 0 5dBm 0 2dBm 10dBm 0 2dBm 20dBm 0 2dBm 30dBm 0 2dBm 40dBm 0 2dBm 50dBm 0 2dBm 60dBm 0 2dBm 30dBm 0 0 5dBm 20dBm 0 5dBm 0 5dBm 30dBm 0 2dBm 20dBm 0 2dBm 10dBm 0 2dBm CHECK TEST CARD RETURN LOSS CHECK VF Nm 30Hz to 20kHz CARRIER 600 ohms 1kHz to 150kHz 135 ohms 1kHz to 600kHz 75 ohms 1kHz to 3MHz 600 ohms 900 ohms gt 30dB gt 26dB gt 26dB gt 30dB FILTER RESPONSE CHECKS C MSG 60Hz 55 7dBm 2dBm 200Hz 25dBm 2dBm 500Hz 7
63. D area If it does not replace the battery or check the power source The battery test operates for internal battery office battery or ac power source Set the INPUT switch to NOISE BRDG Select the appropriate weighting filter using the NOISE WTG switch Set the RANGE switch to 110dBrn Depress the NG pushbutton and connect the set to the circuit to be tested Down range for an on scale indication NOTE Dial and talk may be accomplished on the metallic circuit and the connection held by depressing the HOLD pushbutton Table 3 7 Recorder Calibration Determine the input impedance and full scale sensitivity of of 2 recorder and refer to and it your acorder is suitable TT use with this set The dc voltage supplied by the DC MON 310 jack will drive a dc potentiometric recorder requiring 1V or a dc galvanometric recorder requiring 500uA Connect an input voltage to the set and adjust the RANGE switch until a near full scale indication is observed on the meter Connect the recorder plug with the tip negative to the DC MON jack and adjust the input level until the meter indicates OdBm Mark this point on the recorder paper which should be near full scale Decrease the input level to the set until the meter indicates 1dBm Mark this point on the recorder paper Continue this procedure until every major dBm division on the meter has been calibrated on the recorder paper The actual level t
64. ER RESPONSE 30dB down from the reference 1 Set the 654A frequency to 1kHz adjust the output level for 0dBm 5 11 FILTER RESPONSE CHECKS 2 Check the frequencies listed in Table C MSG FILTER RESPONSE 5 5 fbr the tolerances indicated 15kHz FLAT FILTER RESPONSE Table 5 5 Filter Response Checks FREQUENCY PROGRAM dBm 60Hz 200Hz 17 3 2 250Hz 90042 6 6 1 1kHz 0 Ref 0 Ref 2kHz 0 5 1 75 4 8 2 2 5kHz 1 5 2 3kHz 3 3 6 5 2 4kHz 6 5 2 5kHz 6 5 2 6kHz 6 4 3 8kHz 4 3 10kHz 0 5 1 75 8 5 4 12 5kHz 1 5 2 15kHz 3 3 3555 1 Reset the 654A output level for 0dBm indication on the 3555B meter at a frequency of 1kHz 2 Check the frequencies listed in r the tolerances indicated PROG FILTER RESPONSE 1 Reset the 654A frequency to 1kHz and adjust the output level for OdBm indication on the 3555B meter 2 Check the frequencies listed in Table r the tolerances indicated BRIDGING LOSS a Connect the equipment as shown Figure 5 6land set the 35558 controls as follows FUNCTION VF Nm 600 INPUT TMS BRDG OdBm Adjust the output of the 654A 600 ohm function for indication on the 400FL at a frequency of 1kHz Connect the 3555B to the 400FL input The indication on the 400FL should not drop more than 0 3dB Change the FUNCTION switch CARRIER 600 and repeat the above
65. FACTURERS Continued Code No 91929 91961 92180 92367 92607 92702 92966 93332 93369 93410 93632 93929 94137 94144 94148 94154 94197 94222 94330 94375 94682 94696 95023 95146 95236 95238 95263 95265 95215 95348 95354 95566 95712 95984 95987 96067 Manufacturer Address Honeywell Inc Micro Switch Division PR EY Freeport Nahm Bros Spring edes Oakland Cal Tru Connector Corp Peabody Mass Elgeet Optical Co Inc Rochester N Y Tensolite Insulated Wire Co Inc ter Tarrytown N Y IMC Magnetics Corp Westbury L I N Y Hudson Lamp Kearney N J Sylvania Electric Prod Inc Semiconductor Div Woburn Mass Robbins Myers Inc Pallisades Park N J Stemco Controls Div of Essex Wire Mansfield Ohio Waters Mfg Culver City Cal G V Controls Livingston N J General Corp Bayonne N J Raytheon Co Comp Div Ind Comp Operations Quincy Mass Scientific Electronics Products Loveland Colo Wagner Elect Tung So Div Newark N J Curtiss Wright Corp Electronics Div East Patterson N J South Chester Corp Chester Pa Wire Cloth Products Inc Bellwood 11 Automatic Metal Products Co Brookly
66. Holder fuse 75915 342004 J1 1251 2357 1 Connector AC power cord receptacle 82389 EAC 301 J2 1251 1900 4 Jack telephone 82389 22A obd J3 1200 0163 1 Receptacle 5 pin 74868 78PCG5 J4 1251 1144 1 Jack telephone 82389 MT 342B J5 1251 1143 Jack telephone 82389 MT 332B J6 J7 1251 0065 4 Jack telephone 82389 MT 331 J8 J9 1510 0084 2 Binding post red hp J10 1510 0087 1 Binding post Ass y hp J11 1510 0531 1 Binding post Ass y hp J12 J13 1251 0065 Jack telephone 82389 MT 331 J14 1251 1143 Jack telephone 82389 MT 332B J17 1250 1053 1 Jack coaxial 70674 CJ 1010 J18 1251 1143 Jack telephone 82389 MT 332B L1 9100 1390 1 Inductor audio hp L2 9140 0088 1 Inductor fxd 33uH 5 200mA 95262 NB 0 37 PS M1 1120 0909 1 Meter log calibrated hp 6 7 Section 3555 Table 6 1 Replaceable Parts Cont d REFERENCE hp TQ DESCRIPTION MFR MFR PART NO DESIGNATOR PART NO CHASSIS MOUNTED COMPONENTS Cont d 03555 67902 1 Power Supply Ass y hp R1 0757 0795 1 fxd met flm 75 ohms 1 1 2W 91637 MFF 1 2 T 1 obd R2 0698 4205 1 fxd met flm 21 kilohms 1 1 8W 91637 MF 1 10 32 obd R3 0698 7371 2 fxd met flm 20 605 kilohms 0 1 1 91637 CMF 1 10 32 obd R4 0698 3158 2 fxd met flm 23 7 kilohms 1 1 8W 91637 MF 1 10 32 obd R5 0698 4488 1 fxd met flm 26 7 kilohms 1 1 8W 91637 MF 1 10 32 obd R6 0698 7371 fxd met flm 20 605 kilohms 0 1 91637 CMF
67. L TMS TERM RANGE te 20dBm Adjust the 201C 7 75 on the 3440A 3445A at 100 2 5 3 3555B INDICATION dBm 1MHz to 3MHz 10 0 5 10 of meter indication in dBm 0 20 5 10 of meter indication in dBm 10 0 5 0 of meter indication in dBm 20 0 5 10 of meter indication in dBm 30 0 5 10 of meter indication in dBm 40 0 5 10 of meter indication in dBm 50 0 5 10 of meter indication in dBm Tune the 201 from 100Hz to 20kHz maintaining 7 75V the 3440A 3445A Between 100Hz and 15kHz the 3555B indication must not change more than 0 2dBm Between 15 kHz and 20kHz the indication must not change more than 0 5dBm Check the 30dBm range using the procedure described in Steps j through 1 except change the 3555B range to 30dBm and change the 201C output level for 24 49V n To check the 900 ohm function on the 20dBm and 30dBm ranges connect a 300 ohm 0 1 resistor in series with the 35558 input in Figure 5 3 Change the 3555B to 900 BAL and change the range to 20dBm p Adjust the 201 C output for 9 49V as indicated on the 3440A 3445A Check for the tolerances indicated in 5 4 fbr the 20dBm range Change the 35558 range switch to 30dBm and adjust the 201C for 30V on the 3440A 3445A Check for the tolerances indicated in Table 5 4 for the 30dBm range Table 5 3 Carrier Level Accuracy 3555B Indication dBm 135 1kHz
68. MFR PART NO DESIGNATOR PART NO A2 Cont d R6 0683 1805 1 fxd comp 18 ohms 5 1 4W 01121 CB1805 R7 0698 4342 1 R fxd met flm 90 kilohms 0 1 1 8W 91637 MF 1 10 32 obd 8 0698 4339 1 fxd met flm 11 11 kilohms 0 1 1 8W 91637 1 10 32 R9 0698 5095 1 fxd carbon comp 12 ohms 10 1 2W 01121 CB1201 R10 0698 7328 1 fxd met flm 68 38 kilohms 0 1 1 8W 91637 MF 1 10 32 obd R11 0698 7331 1 met flm 46 28 kilohms 0 1 1 8W 91637 MF 1 10 32 obd R12 Not assigned R13 0698 3150 1 fxd met flm 2 37 kilohms 1 1 8W 91637 1 102 14 0698 3264 1 fxd met flm 11 8 kilohms 1 1 8W 14674 C4 obd 51 3100 1791 1 Switch rotary range 76854 1332 obd A3 03555 66508 1 Board Ass y amplifier hp C1 0160 0763 2 C fxd mica 5pF 10 72136 RDM15COFOKSS C2 0180 0197 5 C fxd 2 2 10 20 vdcw 56289 150D225X9020A2 DYS C3 0180 1746 4 C fxd elect 15uF 10 20 vdcw 56289 150D156X9020B2 DYS C4 0160 2964 6 C fxd cer 0 01uF 80 20 25 vdcw 72982 5835000 Y5UO 10 32 C5 0160 0205 C fxd mica 10pF 5 72136 RDM15C100J58S C6 C7 0160 0378 2 C fxd mica 27pF 5 72136 RDM15E270J5S C8 0121 0105 C var 9 35pF 72982 538400694D C9 0140 0196 1 C fxd mica 150pF 5 72136 RDM15F151J3C C10 0180 0228 10 fxd Ta elect 22uF 10 15 vdcw 37942 TAS226K015P1C C11 0180 0106 1 C fxd 60uF 20 6 vdcw 56289 90803 C12 thru C14 0160 2964 C fxd cer 0 01uF 80 20 25 vdcw 72982 5835000 Y5U 103
69. POWER SUPPLY ASSEMBLY Ci5 D 5 RIA D 528 R29 ROE R67 ROB n22 ES A ores 9 WIRE DESTINATIONS RIg LI 1 So f 0 i 93 20 R24 8 B Si 12 SCHEMATIC LOCATOR A3 UMBER NUMBER hp Part No 03555 66508 1 LUZ W Las COPYRIGHT 1969 BY HEWLETT PACKARD COMPANY Figure 7 3 A2 Range Attenuator and A3 Input Amplifier Schematic and Component Location 7 7 7 8 3595 6 1860 Ra 46 R42 847 R43 CR5 Rag c29 E uM ae R30 1 2 R40 C302 29 CR4 A R288 R28 TR R7 cs ai Ce 4 RI RIO II c2 RI co A4 hp Part 03555 66506 NOTE 1 Refer to Appendix C change no 3 for backdating o eo FROM POWER SUPPLY Aa 10335700000 mE 1 PROG ADJ 048M FLAT 1 1700 F SEE NOTE 1 18 20 Figure 7 4 Filter Schematic and Component Location 7 9 7 10 R26B 100K C MSG 2044 2 1
70. The number of taskhours specified by the work time figure represents the average time required to restore an item assembly subassembly component module end item or system to a serviceable condition under typical field operating conditions This time includes preparation time troubleshooting time and quality assurance quality control time in addition to the time required to perform the specific tasks identified for the maintenance functions authorized in the maintenance allocation char Subcolumn of column 4 are as follows C Operator Crew O Organizational Direct Support H General Support D Depot e Column 5 Tools and Equipment Column 5 specifies by code those common tool sets not individual tools and special tools test and support equipment required to perform the designated function Column 6 Remarks Column 6 contains an alphabetic code which leads to the remark in section IV Remarks which is pertinent to the item opposite the particular code B 4 Tool and Test Equipment Requirements a Tool or Test Equipment Reference Code The number in this column coincide with the numbers used in the tools and equipment column of the MAC b Maintenance Category The codes in this column indicate the maintenance category allocated the tool or test equipment c Nomenclature This column lists the noun name and nomenclature of the tools and test equipment required to perform the maintenance functions d Na
71. UENCY LEVEL MEASUREMENTS 20 2 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 20 2 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 40GB 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
72. URING SET Figure 5 7 Input Balance Test Set Up 5 7 Section V CARRIER 600 and repeat the above procedure Between 1kHz and 10kHz the balance must be greater than 7098 Between 10kHz and 100kHz the balance must be better than 60dB Between 100kHz and 600kHz balance must be better than 40dB 5 14 ADJUSTMENT AND CALIBRATION PROCEDURE 5 15 The following is a complete adjustment and calibration procedure for the Model 3555B These adjustments should be performed only after it has been determined by the performance checks that the set is not operating within its published specifications 5 16 POWER SUPPLY CHECK 5 17 Before attempting the following calibration procedures first check the power supply voltage to be sure that it is correct and that the ripple voltage is not abnormal To do this perform the following steps NOTE Calibration of the 3555B should be performed with the set operating from the internal battery except for the power supply ripple check in the following steps Operate the set from the ac power source long enough to make this check and then return the set to internal battery operation This is accomplished by changing the position of the slide switch mounted on the side of the set When operating from the battery disconnect the ac power cord from the set a Remove the set from the case and connect the 3440A 3445A dc voltmeter between the 20V supply and ground The negative side
73. anual 2 3 WARRANTY EXCEPTION 2 4 The battery supplied with the 3555 is warranted for a period of 60 days beginning at the time of receipt of the set This warranty is based on an expected battery life of 180 hours at 4 hours per day at 700 as specified Table 1 1 in this Manual 2 5 POWER REQUIREMENTS 2 6 This set is designed to operate from an internal 45 volt dry cell battery an external 24 to 48 volt CO battery or from an ac power source 115 230V 48 to 440Hz The power source is selected by the AC BAT switch on the side of the set The line voltage is selected by the 115 230 volt slide switch on the rear of the set The set is protected by a 0 1 5A slow blow fuse 2 7 THREE CONDUCTOR POWER CABLE 2 8 To protect operating personnel the National Electrical Manufacturers Association NEMA recommends that the panel and cabinet be grounded This set is equipped with a three conductor power cable which when plugged into an appropriate receptacle grounds the set The offset pin on the power cable three prong connector is the ground wire This power cable is detachable from the set and is stored inside the front cover 2 9 illustrates the standard power plug configurations that are used throughout the United States and in other countries The hp part number shown directly below each plug drawing is the part number for a 3555B power cord equipped with the proper plug If the appropriate power cord is not inc
74. arson 5 TRADOC 2 Ft Gillem 10 OS Maj Comd 4 Ft Gordon 10 TECOM 2 CERCOM Ofc USACC 4 USA Dep 1 MDW 1 Sig Sec USA Dep 1 Armies 2 Army Dep 1 except Corps 2 LBAD 14 Svc Colleges 1 SAAD 30 USASIGS 5 TOAD 14 USAADS 2 SHAD 3 USAFAS 2 Units org under fol TOE USAIS 2 29 207 2 USAFS 2 29 610 2 ARNG None USAR None For explanation of abbreviations used see AR 310 50 RECOMMENDED CHANGES EQUIPMENT TECHNICAL PUBLICATIONS SOMETHING WRONG wim ms FROM YOUR UNIT COMPLETE ADORESS THEN DOWN THE ABOUT ON THIS FORM CAREFULLY TEAR OUT FOLD IT AND DROP IT IN THE MAIL PUBLICATION NUMBER PUBLICATION DATE BE EXACT PIN POINT WHERE IS idi D AC 2028 2 PREVIOUS EDITIONS 5 YOUR OUTFIT WANTS TO KNOW ABOUT YOUR RECOMMENDATION MAKE CARBON COPY OF THIS AND GIVE IT TO YOUR HEADQUARTERS IN THIS SPACE TELL WHAT 18 WRONG AND WHAT SHOULD DONE ABOUT IT Qu qw s qu s Q w mua s r s TEAR ALONG PERFORATED LINE wawas amam omama rss GENER sq a 043606 000
75. at the meter always indicate in DBM regardless of the impedance selected additional gain switching must be performed When the 75 function is chosen A3K2 energizes and places 16 in parallel with A3R14 and 5 This reduces the negative feedback with respect to the 600 function and increases the amplifier gain by 9dB When the 135 function is selected A3R22 R23 R24 are connected in series with A3R16 This combination is then in parallel with A3R14 and 15 reducing the feedback and increasing the amplifier gain by 6 4dB with respect to the 600 function When the 900 function is depressed 17 9 and 20 are connected in parallel with A3R13 increasing the negative feedback and ATTENUATOR PAL p reducing the amplifier gain by 1 7dB Relays A3K1 thru are controlled by the FUNCTION switch when any of the impedance functions except 600 are selected 4 24 Transistors and 2 form a differential amplifier The signal is taken from the collector of A3Q1 amplified by A3Q4 and A3Q5 with A3Q5 providing feedback to the base of A3Q2 Transistor provides isolation between A3Q2 and A3Q4 to prevent undesired feedback This results in a greater bandwidth than could be achieved without its use The output signal is coupled through A3R17 and A3C10 to the INPUT switch 4 25 FILTERS Schematic No 3 4 26 The 3555B contains 3kHz FLAT weighting filter C MSG weighting filte
76. ations below Typical manufacturer of the part in a five digit code Sod spoon list manufacturers d Manufacturer s part number 6 3 Miscellaneous parts are listed at the end of 6 4 ORDERING INFORMATION 6 5 part note the manufacturer s part number 6L MFR PART NO and then cross reference that number in the cross reference index Table 6 2 Order the part through normal channels If the NSN is not listed for the part in Table 6 2 order by MFR PART NO and the manufacturer s identification number listed under the MFR number in Table 6 1 ABBREVIATIONS Do silver inside 103 seconds SPDT single pole double throw impg impregnated nar not separately replaceable SPST single pole singe throw incd incandescent insulation ed 0 2 ohm s Nac T E T tantalum order by description temperature coefficient kilohm s 10 ohms outside diameter MiO c titanium dioxide cer ceramic kilohertz 10 en eee OP toggle coef coefficient Pau u unn naa peak tol inductor Pa picoampere s trimmer comp composition lin
77. being made The output of the 40dB attenuator is always applied to the voice frequency transformer 4 11 The DIAL BAT function serves two functions First it connects the DIAL AC MON jacks to the INPUT jacks so that a handset can be used for dialing Secondly the meter is connected to the unregulated power supply so that the battery condition can be monitored 4 12 After the signal is conditioned by the input circuitry it is coupled to the RANGE attenuator where the signal level is adjusted to provide the proper input for the Input Amplifier The RANGE attenuator provides from OdB to 80dB of attenuation It also provides gain switching for the Input Amplifier OETECTOR 35538 8 056 Figure 4 1 Simplified Block Diagram 4 1 Section 4 13 The output the Input Amplifier goes to the INPUT switch where noise filters are set up for selection by the NOISE WTG switch the NOISE position either 3kHz FLAT weighting C Message weighting 15kHz FLAT weighting or PROGRAM weighting can be selected by the NOISE WTG switch the TMS position of the INPUT switch the filters are bypassed for transmission level measurements 4 14 The output from the INPUT switch goes to the meter amplifier This amplifier provides an ac signal to the DIAL AC MON jacks so that a handset can be used to listen to the signal being measured This is particularly useful in determining noise characters 4 15 The detector circuit provides an equiva
78. ble 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 15 Model 35558 Section GENERAL INFORMATION 1 1 INTRODUCTION provided balanced or unbalanced bridged or terminated For noise measurements a noise to ground 1 2 The Hewlett Packard Model 3555 Ng function is provided which provides 40dB of Transmission and Noise Measuring Set is a versatile set designed for uses testing telecommunications equipment The extreme sensitivity of this set linked with its wide and flat frequency response make it suitable for noise and level measurements at voice program and carrier frequencies Levels from 80dBm to 30dBm 10dBm to 120dBm full scale can be measured and displayed on a meter calibrated to indicate both in dBm for level measurements and in dBm for noise measurements 1 3 The set combines the features of a voice and noise frequency measuring set and the features of a carrier frequency measuring set For voice and program frequencies impedances of 900 ohms and 600 ohms are TRANSMISSION amp NOISE WIASURW SET
79. ccuracy Checks 600 BAL and 900 BAL 80dBm through 30dBm RANGE 30dBm 20dBm 10dBm 10dBm 20dBm 30dBm 40dBm 50dBm 60dBm 70dBm 80dBm z0Hzto20kHz aotizto 100Hzto 20kHz 100Hz to 30 0 5 30 0 2 20 0 5 20 0 2 10 0 5 10 0 2 Model 3555 VOLTMETER 400FL TEST hp654A LINE MATCHING TRANSFORMER L 35555 5 887 Section IV hp3555B TRANSMISSION amp NOISE MEASURING SET SHORT CLIP LEADS Figure 5 4 Return Loss Test Set Up Open 51 and down range the 400FL for an on scale indication This indication subtracted from the reference established in step c is the bridge balance and should be greater than the return loss specification Unplug or disconnect in Figure 5 4 hnd connect the 3555B tip and ring in its place Be sure to use short clip leads Momentarily close S1 and recheck the reference on the 400FL S1 in Figure 5 4 hnd down range the 400FL for an on scale indication This indication must down at least 30dB from the reference Tune the 654A from 50Hz to 20kHz The 400FL indication must remain at least 3048 down from the reference TEST OSCILLATOR 654A DEPRESS ES 0 BALe 35558 8 1880 USE CABLE FIG 5 FIG 5 1 h Change the 3555B FUNCTION to CARRIER 600 BAL and repeat steps f and g between 3kHz and 150kHz Return loss must be at least 26dB
80. cks 12 and DIAL AC MON jacks 10 11 Shorting Strap swing away shorting strap connecting the S and G terminals together which may be used to isolate the jack sleeves from case ground Not for use with type 347 plugs WTG Switch Selects weighting filters for noise measurements These filters are selectable only when the INPUT switch is in one of the two NOISE positions 3kHz FLAT C MSG 15kHz FLAT and PROG filters all conform to the standards set up by the Bell System and Edison Institute for measuring message circuit noise RANGE SWITCH Selects dBm or dBm ranges of input sensitivity The RANGE switch markings correspond to the 0 markings on the meter scale 6 The black markings are dBm for transmission measurements and the blue markings are dBrn for noise measurements RESPONSE Switch Selects NORM meter response for transmission level measurements or DAMP for noise measurements where noise is impulsive in nature Meter A taut band individually calibrated meter with shaped pole pieces to provide a linear dBm indication with equal accuracy and resolution over the entire meter scale The dBm scale is marked in black and has 0 14 resolution for transmission measurements The 0 marking at the right end of the scale corresponds to the black RANGE switch setting The dBm scale is marked in blue for noise measurements The 0 marking at the left end of the scale corresponds to the blue RANGE switch setting The gree
81. cteristics of this set with no warm up time required allows turning off between measurements NOTE If the battery voltage indication drops below the left end of the arc on the meter face the set will not operate properly This will be noted by a slow oscillation of the meter If this symptom is encountered depress the DIAL BAT pushbutton and check the battery condition If the indication is to the left of providing connection to the input circuitry of the measuring set When the DIAL BAT pushbutton is depressed the INPUT jacks are connected in parallel with the DIAL AC MON jacks Battery Cover Removeable by four 1 4 turn screw fasteners 10 expose the internal battery for replacement 48V 310 A jack accepting a Western Electric 310 plug with tip negative and sleeve ground to supply external office battery power to the set Insertion of a 310 plug into this jack disconnects the internal battery The BAT AC switch 16 must be set to BAT for office battery operation CAUTION WHEN OPERATING FROM AN EXTERNAL BATTERY CORD SHOULD BE CONNECTED TO MEASURING SET FIRST THEN PLUG INTO BATTERY SUPPLY TO AVOID SHORTING THE OFFICE BATTERY 15 0 15A SPARE Fuse A 0 154 slo blo fuse and spare for measuring set protection when operating from AC power Fuses are not used when the set is battery powered BAT AC Switch A slide switch for selecting the ac power source or the internal battery and office battery jack 14 power source T
82. cy band as the desired signal and can be detected 3 56 Referring tol Figure 3 7 one line is designated A B and the other designated C D with A and C representing the near end of one of the pairs and band D representing the far end of the other pair First measure the transmission loss between A and B Then measure the transmission loss from A to D The crosstalk coupling loss in dBx is the difference in the reading from A to B and the reading from Ato D 3 57 IDENTIFYING NOISE CHARACTERISTICS 3555 TRANSMISSION 8 NOISE MEASURING SET Figure 3 6 Typical Test Setup for Measuring Insertion Loss 3 10 3555 hp3555B OSCILLATOR hp236A MEASURING SET DISTURBING 8 PAIR A TRANSMISSION amp NOISE Section 35558 TRANSMISSION 8 NOISE MEASURING SET OSCILLATOR lt NN CROSSTALK COUPLING eben 35558 8 i875 Figure 3 7 Test Setup for Measuring Crosstalk Coupling Loss 3 58 Normally a frequency selective voltmeter is used to identify the characteristics of transmission line interference in order to trace it down to its origin and apply the appropriate corrective action As an expedient for troubleshooting there several subjective measurements that the 236A 3555B can make to help identify the interference characteristics 3 59 Since power line noise is the most common nuisance a quick check with the 3555B should be mad
83. d from the amplifier ac output and connected to the INPUT Jacks This permits connecting the lineman s handset to the balanced line for the purpose dialing Ng Se Figure 4 3 The Ng pushbutton connects a 40dB attenuator across the balanced input terminals for longitudinal measurements This attenuator consists of A1R5 thru A1R8 and A1C1 The output is taken from the junction of AIC1 and A1R8 This output is referenced to ground and applied to the voice frequency transformer A1T2 900 Vf Nm The 900 function switch 54 selects terminating resistors and A1R9 for 900 ohm terminations The INPUT switch must be in _ the TERM position to complete the circuit for this termination The 900 function switch also places a ground on the 900 ohm relay A3K1 which provides gain switching in the Input Amplifier so that the meter will indicate in dBm The 900 ohm signal is applied to the voice frequency transformer A1T2 HOLD can be accomplished on this function Figure 4 2 Simplified DIAL BAT Function 3555 TIP INPUT RING INPUT Section IV Figure 4 3 Simplified NG Function e 600 Vf Nm The 600 function switch S5 selects terminating resistors A1R2 and A1R10 for a 600 ohm termination The INPUT switch completes the circuit for this termination The 600 Vf Nm signal is applied to T2 gain switching is performed in this function since the set is normalized at 600 ohms HOLD can be accomplished o
84. d measurement is 40dB less sensitive than the noise metallic measurement because of the voltage divider in the input circuit This requires adding 40dB to the meter indication to arrive at the correct noise to ground level The level is the algebraic sum of the blue RANGE switch setting and the blue meter scale indication plus 40dB For example RANGE is set to 20dBm and the meter indicates 3dBm The noise to ground level is 20 3 40 63dBm Some telephone company operating procedures disregard the 40dB correction factor in which case the noise to ground level would be 20 3 23dBm 3 38 The Nm and Ng indications can be used to compute the balance of a facility since balance is defined as the degree of rejection of longitudinal signals The degree of balance in dB where the major part of noise metallic is due to noise to ground is given by the equation Balance in dB Nm Ng For example if the noise metallic level of a circuit is 26dBm and the noise to ground of the same circuit is 9OdBmC the balance in dB is 26 90 64dB In the case mentioned above where the 40dB correction factor is neglected the balance in dB Nm Ng 40 3 39 Other general purpose uses of the 35558 are volume and crosstalk measurements ballistic characteristics of the set make it approximately correct for VU measurements The RANGE switch should be adjusted until the meter pointer fluctuations are on scale and should be observed for
85. de to Name and their latest supplements The date of revision and the date of the supplements used appear at the bottom of each page Alpha betical codes have been arbitrarily assigned to suppliers not appearing in the H4 Handbooks Revised May 1970 Code No 05347 05397 05574 05593 05616 05624 05728 05729 05783 05820 06004 06090 06175 06402 06540 06555 06666 06751 06812 06980 07088 07126 07137 07138 07149 07233 07256 07261 07263 07322 07387 07397 07700 07829 07910 07933 07980 08145 08289 08358 08524 08664 08717 08718 08727 08792 08806 08984 09026 09097 09134 09145 09250 09353 09569 09795 09922 10214 10411 10646 Manufacturer Address Ultronix Inc San Mateo Cal Union Carbine Corp Elect Divi chases WR Rhe New York N Y Viking Ind Inc Canoga Park Cal Icore Electro Plastics Inc Sunnyvale Cal Cosmo Plastic c o Electrical Spec Cleveland Ohio Barber Colman Co Rockford Ill Tiffen Optical Co TA wtb Genius Roslyn Heights Long Island Metro Tel Westbury N Stewart Engineering Co Santa Cruz Cal Wakefield Engineering Inc Wakefield Mass Bassick Co Div of Stewart Warner Corp Raychem Corp Bausch and Lomb Optical Bridgeport Conn Redwood City Cal
86. down from the reference Change the bridge resistors ith Figure 5 4 to 900 ohms f 0 1 use 300 ohms 0 1 in series with 600 ohms 0 1 and change the 3555B FUNCTION to VF Nm 900 BAL Be sure to reset the reference level after the resistors are changed Check the return loss between 50 Hz and 20 kHz The return loss must be better than 30 5558 TRANSMISSION 8 NOISE MEASURING SET Figure 5 5 Filter Response Test Set UP Section 3555 55558 TRANSMISSION 8 NOISE MEASURING SET AC VOLTMETER TEST hp 400FL 6 54 Figure 5 6 Bridging Loss Test Set Up j Change the bridge resistors irl Figure 5 4 to 1 Connect the equipment as shown in 135 ohms 0 1 and change the 3555B Figure 5 5 with S1 in position 1 FUNCTION to 135 BAL Check the return set the 3555B controls as follows loss between 1kHz and 600kHz The return loss must be better than 26dB down FUNCTION VF Nm 600 from the reference INPUT NOISE BRDG k Change the 3555B input connection to the RANGE 75 UNBAL jack Change the resistors Figure 5 4 75 ohms 0 1 and change 2 Adjust the output of the 654A for the 3555B FUNCTION to CARRIER 75 OdBm at a frequency of 1 kHz UNBAL 3 Check the frequencies listed Table Check the return loss between 1kHz and 5 5 fbr the tolerances indicated 2 The return loss must be better than b 3kHz FLAT FILT
87. e first By noting the difference in noise readings between the 3kHz FLAT and C message weighted modes an indication of line frequency disturbance can ascertained if the 2 flat mode shows a substantially higher reading 3 60 As a further aid in identifying noise the lineman s handset can be connected to the AC MONITOR terminals and an aural analysis made Although the handset will not respond to 60Hz line interference is usually very rich in odd harmonics and 180Hz can easily be identified This test also helps to identify babble and other audio frequency interference 3 61 Vagrant noise such as atmospheric noise can be analyzed by connecting a strip chart recorder to the DC MONITOR terminals Long term seasonal and temperature effects can also be measured very conveniently with a recorder 3 62 Frequency of strong interfering periodic signals such as radio transmitters can be roughly determined with the 236A and 35558 The 236A is connected to one end of the line and the 3555B to the remote end as with transmission loss measurements The oscillator output is increased until the test meter barely indicates a signal above the noise The oscillator frequency is then changed very slowly while the repairman observes the 35558 for a beat By tuning for a beat the frequency of the interfering signal can be read directly off the 3 11 oscillator frequency dial to an accuracy of approximately 2395 In practice this measurem
88. e and adjust A1C4 for minimum indication on the 3555B meter This indication must be down at least 40dB BALANCE CHECK a First check the balance as described in paragraph 5 13 to be sure that the balance does not meet specifications If it does disregard this step If it does not perform the following procedure Since there are no adjustments for balance it will be necessary to change the value of a fixed factory selected capacitor To adjust the balance on the Section V CARRIER function change C4 To change the balance on VF Nm change the value of A1C9 c To determine whether the value of these capacitors should be increased or decreased lightly touch the tip and ring banana jack insulators and watch the direction in which the meter indication goes The side tip or ring that causes the meter indication to decrease needs added capacitance The capacitance should be changed in very small steps and checked again FILTER CALIBRATION a Connect the equipment as shown 5 S1 in position 1 and set the 35558 controls as follows 5 24 INPUT SE NOISE TERM NOISE WTG 3kHz FLAT b Connect a frequency counter to the 3555B AC MON terminals and adjust the 654A frequency to exactly 1 00kHz as indicated on the frequency counter Adjust the 654A output level for exactly 0dBm Adjust A4R3C for 0dBm indication on the 3555B meter d Change the NOISE WTG switch to 15kHz
89. eable equipment to like new condition in accordance with original manufacturing standards Rebuild is the highest degree of materiel maintenance applied to Army equipment The rebuild operation includes the act of returning to zero those age measurements hours miles etc considered in classifying Army equipments components B 3 Column Entries a Column 1 Group Number Column 1 lists group numbers the purpose of which is to identify components assemblies subassemblies and modules with the next higher assembly b Column 2 Component Assembly Column 2 contains the noun names of components assemblies subassemblies and modules for which maintenance is authorized c Column 3 Maintenance Functions Column 3 lists the functions to be performed on the item listed in column 2 When items are listed without maintenance functions it is solely for purpose of having the group numbers in the MAC and RPSTL coincide d Column 4 Maintenance Category Column 4 specifies by the listing of a work time figure in the appropriate subcolumn s the lowest level of maintenance authorized to perform the function listed in column 3 This figure represents the active time required to perform that maintenance function at the indicated category of maintenance If the number or complexity of the tasks within the listed maintenance function vary at different maintenance categories appropriate work time figures will be shown for each category
90. ear taper pc printed circuit TSTB transistor connection ogarithmic taper picofarad s 1072 farads 8 deposited mA milliampere s 10 amperes Vacw alternating current double pole double throw MHZ megahertz 1079 hertz working voltage MM double pole single throw megohm s 10 ohms position s variable mot DINE a uu uuu metal film poly polysterene UOC electrolytic mfr manufacturer pot potiometer je encapsulated ms millisecond p p peak to peak watt s HI RR mounting PON ces parts million i farad s WAY millivolt s 10 volts precision temperature FET effect transistor microfarad s coefficient long term sta o fixed US microsecond s bility and or tolerance RE UN ESN E uV microvolt s 10 volts GaAs gallium arsenide W Reuss resistor optimum value selected at gigahertz 10 hetz 0 0 rhodium factory average value guard ed nanoampere s 10 amperes Foot mean square shown part may be omitted Ge germanium T unas ME normally closed rot
91. easuring and diagnostic equipments used in precision measurement Consists of comparisons of two instruments one of which is a certified standard of known accuracy to detect and adjust any discrepancy in the accuracy of the instrument being compared 9 Install The act of emplacing seating or fixing into position an item part module component or assembly in a manner to allow the proper functioning of the equipment or system h Replace The act of substituting a serviceable like type part subassembly or module component assembly for unserviceable counterpart Repair The application of maintenance services inspect test service adjust align calibrate replace or other maintenance actions welding grinding riveting straightening facing remachining resurfacing to restore serviceability to an item by correcting specific damage fault malfunction or failure in a part subassembly module component or assembly end item or system B 1 j Overhaul That maintenance effort service action necessary to restore an item to a completely serviceable operational condition as prescribed by maintenance standards DMWR appropriate technical publications Overhaul is normally the highest degree of maintenance performed by the Army Overhaul does not normally return an item to like new condition k Rebuild Consists of those services actions necessary for the restoration of servic
92. ecision Electric Co Skokie Ill Sperti Faraday Inc Copper Hewitt Electric Div Hoboken N J Regolatot Corp Norwalk Corn Jeffers Electronics Division of Speer Carbon Co Fairchild Camera amp Inst Corp Space amp Defense Systems Div N J Magurie Industries Inc Greenwich Conn Sylvania Electric Prod Inc Electronic Tube Division Astron Newark Harrison J Du Switchcraft Inc Chicago Ill Metals amp Controls Inc Spencer Products Attleboro Mass Phillips Advance Control Joliet Research Products Corp Madison Wis Rolton Mfg Co Inc Woodstock N Y Vector Electronic Glendale Cal Carr Fastener Cambridge Mass New Hampshire Ball Bearing Inc Peterborough N H General Instrument Corp Capacitor Div Darlington S C ITT Wire and Div Los Angeles Cal Victory Eng Corp Springfield N J Bendix Corp Red Bank Red Bank N J Hubbell Corp Mundelein Ill Rosan Inc Newport Beach Cal Smith Herman H Inc Brooklyn N Y Tech Labs Palisades Park N J Central Screw Chicago Wire and Cable Co Div Amerace Brookfield Mass Burroug
93. eet will be supplied to make this manual compatable with newer instruments or the backdating information in Appendix d will adapt this manual to earlier instruments All correspondence with Hewlett Packard should include the complete serial number 1 13 150 BAL MODIFICATION 1 14 The Model 3555B is shipped from the factory with a 135 BAL function If a 150 BAL function is desired instead of the 135 BAL function the set can be converted by simply clipping a shorting wire within the set applying a 150 BAL decal supplied with the set over the 135 BAL decal and making only one adjustment 1 15 For detailed instructions on modification of the set refer to Paragraph 5 6 If your set is known to be within specification tolerances a simplified procedure can be used to modify the set and is described in Paragraph 3 69 Model 35558 Section ll SECTION II INSTALLATION 2 1 INSPECTION Table 2 1 Suitable Batteries Meeting NEDA 202 Specifications 2 2 set was carefully inspected both No mechanically and electrically before shipment It should be physically free of mars or scratches and in perfect electrical condition on receipt To confirm this the set should be inspected for physical damage in transit for supplied accessories and for electrical performance outlines the electrical performance checks using test equipment listed in Table 5 1 If there is damage or deficiency see the warranty in the front of this m
94. egulated power supply voltage can be monitored 1 7 Jacks accepting Western Electric type 241 309 310 347 and 358 plugs are provided for INPUT connections to the 3555B Dual binding posts accept banana plugs wires lugs or phone tips and a pair of special connectors permit the attachment of clip leads from a lineman s handset 1 8 The Model 3555B can be operated from either the internal 45V dry cell battery or from the ac line 115 or 230Vac 48Hz to 440Hz A special device is included in the cover to automatically turn the set off when the cover is replaced The set can also be operated from the central office battery A jack is provided on the side of the set for this purpose 1 9 ACCESSORY EQUIPMENT SUPPLIED 1 10 The accessory equipment supplied with the Model 3555B is listed in Table 1 2 1 2 Model 3555B Table 1 2 Accessory Equipment Supplied 8120 1348 Power Cord 1470 0026 Battery 45 Volt dry cell 03555 26510 5000 7135 1 Test Board 1 Decal 150 BAL 1 1 11 INSTRUMENT IDENTIFICATION 1 12 Hewlett Packard uses a two section serial number The first section prefix identifies a series of instruments last section suffix identifies particular instrument within the series If a letter is included with the serial number it identifies the country in which the instrument was manufactured If the serial prefix of your instrument differs from the one on the title page of this manual a change sh
95. either bridging or terminated In this position the set has its maximum frequency range 3 17 The multiple INPUT jacks and binding posts accept the Western Electric 309 310 and 358 single plugs and the 241 or 289 twin plug The two red binding posts marked tip and R ring will accept banana plugs spade lugs phone tips or bare wires These jacks and binding posts are all connected in parallel and only one should be used at a time patching cord such the Western Electric 3P12H consisting of a cord with a 310 plug on one end and a 309 plug on the other end should be kept with the instrument as a universal patch cord The 75 ohm jack accepts Western Electric type 358 plugs for 75 ohms unbalanced carrier measurements 3 18 The sleeves of all the INPUT and DIAL jacks are connected together and to the black binding post marked S The binding post in turn is connected through a swing away shorting strap to a second black binding post marked G This binding post is the measuring set case ground When it is necessary to establish a battery or ground connection on the sleeve for PBX test purposes this shorting strap may be disconnected by loosening the black binding posts and swinging away the strap A cord is then connected to the S terminal and may be connected to the battery or ground for the test Type 347 plugs must not be used when the shorting strap is removed 3 19 The multiple jacks marked DIAL AC MON are connected in pa
96. elect the attenuator pads and or gain switching resistors that match your symptom and check them THE INPUT Check the dc voltages as indicated in Figure 7 3 to determine if a catastrophic failure does exist If the dc voltages are abnormal greater than 10 of the indicated level check for open or shorted components in the area of the abnormal indication 5 36 AMPLIFIER a b Check to see that 2 are operating properly All relays are de energized when either of the 600 BAL FUNCTION pushbuttons is depressed Depress each of the other impedance functions 900 BAL 135 BAL and 75 UNBAL to see that and A3K2 respectively energize and de energize properly If any relay fails to operate 5 14 5 37 a b 5 38 TROUBLESHOOTING Model 3555B properly check the relay and the energizing ground supplied through either pins 1 2 FILTER TROUBLESHOOTING First determine that the set is operating in the TMS input mode This bypasses the filters If the set functions properly in the TMS mode check each of the filters by applying a 1kHz signal at a OdBm level to the set All filters are calibrated for 0dBm indication on the 3555B meter at a frequency of 1kHz Since all the amplifiers Figure 7 1 are used in C MSG the loss of any one will obviously cause the loss of the C MSG weighting However the bad amplifier can be isolated by checki
97. ent would probably be made using a loop around technique The oscillator would be connected to a quiet line at the remote location and this line would be tied to the noisy line back at the central office This permits one man to operate both the oscillator and the test meter 3 63 When a current flows through a conductor it sets up two distinct fields around the conductor the electrostatic capacitive field and the magnetic inductive field Both are capable of inducing longitudinal voltages in adjacent conductors and both increase in proportion to the power and frequency of the current from which they result They differ greatly however in how they affect nearby circuits The voltage resulting from magnetic induction varies inversely with the impedance of the line That is the higher the line impedance the less voltage that can be induced by a magnetic field Capacitively coupled voltage on the other hand increases in direct proportion to line impedance the higher the impedance the greater the Capacitive coupling By means of a simple test it is possible to identify the coupling between two lines as shown in Since induced voltages are inversely proportional to line impedance the voltage coupled from pair A into pair 3 88 will increase as the impedance is lowered shorted Conversely since capacitively coupled voltages are directly proportional to impedance the coupled voltage 388 would
98. er source before attempting to make any measurements The battery test operates for internal battery office battery or ac power source Select either 5 BRDG or TMS TERM depending on the measurement being made The weighting filters are not in the circuit at this time Select the impedance FUNCTION pushbutton to match the circuit to be tested Select either 900 BAL or 600 BAL VF Nm for frequencies between 20Hz and 20kHz Select 600 BAL or 135 BAL CARRIER for balanced measurements between 1 kHz and 600kHz Select 75 UNBAL for 75 ohm unbalanced measurements between 30Hz and 3MHz Set the RANGE switch to 30dBm Set the RESPONSE switch to DAMP Connect the set to the line using a suitable patch cord For balanced measurements use a cord having a 309 or 310 single plug a 241 dual plug or banana plugs bare wires or clip leads For unbalanced carrier measurements 75 ohm only use a cord having a 358 plug NOTE Carrier measurements are limited to the 50dBm RANGE thru the 10dBm RANGE Down range the RANGE switch for an on scale indication Level is equal to the algebraic sum of the black RANGE setting plus the black meter scale indication EXAMPLES RANGE 50dBm METER 1dBm LEVEL 49dBm RANGE 20dBm METER 4dBm LEVEL 16dBm Turn the POWER switch to ON and depress the DIAL BAT pushbutton The meter should indicate in the green BAT GOOD area If it does not replace the battery or check the power source
99. et TMS so that the loss can be measured in both directions If the line that is being tested passes through central office switching equipment the oscillator or TMS at the remote end is placed in the DIAL mode and the lineman s handset connected to the DIAL posts permitting the repairman to bypass the instrument circuitry and dial his test board at the central office Tests are then made in the 600 or 900 ohm HOLD positions which provide a dc path to hold the switching relays OSCILLATOR hp 236A 35558 8 1876 CIRCUIT UNDER TEST Model 3555B 3 53 CROSSTALK MEASUREMENTS 3 54 Crosstalk is interference on a transmission line caused by inductive and capacitive coupling between pairs of transmission lines in close proximity Crosstalk can be classified as near end and far end Far end crosstalk is interference at the end of the transmission line opposite the signal source while near end crosstalk is interference detected at the same end the line as the signal source Table 3 2 Crosstalk Correction Factor dB Correction Factor Crosstalk in dB Crosstalk Noise Minus Correction Factor Crosstalk Noise in dB Minus Noise Alone in dB 4105 6 to 8 9 and above 3 55 Since different frequency bands are used for each direction of transmission on two wire carrier systems near end crosstalk cannot be detected The situation is quite different however for far end crosstalk since it is in the same frequen
100. gure 3 5 Simplified Send Receive Test Set up 3 9 Section 236A FUNCTION switch to 600 HOLD 900 HOLD depending on the impedance required To receive a tone set the 3555B FUNCTION switch to either 600 HOLD or 900 HOLD whichever is appropriate and change the 236 FUNCTION switch to DIAL send again simply change the 236A to 600 HOLD or 900 HOLD If holding is not required or dialing is not required simply select the impedance and switch back and forth on the 236 FUNCTION switch 3 48 TRANSMISSION LOSS MEASUREMENTS 3 49 Transmission loss is defined as the ratio of power from a transmission line by a receiving terminal to the power available from the sending equipment and is dependent on three factors power dissipated by the dc resistance of the line power losses because of impedance mismatch power transferred to other circuits by inductive or capacitive coupling See Figure 3 6 3 50 These factors are difficult to measure separately Their sum however is relatively easy to measure with the hp 236A 3555B combination 3 51 Figure 3 6 shows a typical transmission loss measurement setup The oscillator is adjusted for a reference level and the signal is measured at the other end of the line with a level meter Loss measurements are usually made at various frequencies to determine the response of the line 3 52 Ideally the man at each end of the line will have both an oscillator and a Transmission Measuring S
101. gure 7 1 of the 3555B serves the dual purpose of showing how various circuits are arranged to form the set and at the same time gives voltages and adjustments for use in troubleshooting the set This functional block diagram should be used in conjunction with the troubleshooting procedure described inf Section V 7 5 DIAGRANS 7 6 schematic diagrams Figures 7 2 througH 7 5 lcontained in this section show the detailed circuits in the Model 3555B Components marked with an asterisk are those that are critical in value The value of these components may vary slightly from one set to another due to variations in transistor Beta etc and the values shown on the schematic are average 7 7 Voltage levels have been included the schematics which should greatly assist troubleshooting the set When measuring these voltages a high input impedance voltmeter 1 megohm or greater should be used to prevent circuit loading REFERENCE DESIGNATIONS PARTIAL REFERENCE DESIGNATIONS ARE SHOWN PREFIX WITH ASSEMBLY OR SUBASSEMBLY DESIGNATION S OR BOTH FOR COMPLETE DESIGNATION ASSEMBLY SUBASSEMBLY A2 2 1 NONE NONE Assembly Reference Desi Plug P2 mounted on Assembly or part of the Assembly Board Jack J2 mounted on Chassis or another Assembly J2 Wire Color Color code same as resistor color code First number indicates base color second number indentifies wider st
102. he switch may be operated by a small screwdriver or pointed tool inserted into the slot in the switch AC Power Receptacle A 3 prong power receptacle for the special power cord stored inside the front cover The switch 16 must be positioned to AC for this power source 16 the arc on the meter face replace the battery 3 12 LEVEL NOISE MEASUREMENTS 3 13 Since the 3555B is both a level measuring set and a noise measuring set the procedure for making these measurements will be treated separately Level measurements can be made at voice frequencies and carrier frequencies Since the procedure for making voice Carrier level measurements identical except for the FUNCTION pushbutton utilized only one procedure will be described in detail 3 14 LEVEL MEASUREMENTS 3 15 The 35558 can be used as a wide range and wide Section frequency Transmission Measuring Set TMS for voice program and carrier multiplex measurements The set will operate over a wide range of environmental conditions and maintain a high degree of accuracy 3 16 general transmission level measurements are made by connecting the circuit under test to the INPUT jacks with a suitable patch cord selecting the proper bridging or terminate condition and impedance and then operating the RANGE switch to provide an on scale meter indication Transmission level measurements are made with the INPUT switch in TMS position
103. hs Corp Electronic Plainfield N J Union Carbide Prod York N Y Model Eng and Mfg Inc Huntington Ind Loyd Scruggs Festus Mo Aeronautical Inst 4 Radio Lodi N J Arco Electronics Great Neck N Y A J Glesener San Francisco Cal TRW Capacitor Div Ogallala Neb From Handbook Supplements 4 1 Dated January 1970 Code 810 5454 85471 85474 85660 85911 86174 86197 86579 86684 86928 87034 87216 87473 87664 87930 88140 88220 88698 89231 89473 89479 89665 90030 90179 90365 90763 90970 91146 91260 91345 91418 91506 91637 91662 91673 91737 91827 91886 CODE LIST OF MANUFACTURERS Continued Manufacturer Address Sarkes Tarzian Inc Bloomington Ind Boonton Molding Boonton N J A B Boyd San Francisco Cal R M Bracamonte amp Co San Francisco Cal Koiled Hamden Conn Seamless Rubber Chicago Fafnir Bearing Co Los Angeles Calif Clifton Precision Products Co Inc bs GME as Clifton Heights Pa Precision Rubber Products Corp Dayton Ohio Radio Corp of America Electronic Comp amp Devices Division Harrison N J Seastrom Mfg Glendale Cal Marco Industries
104. increase as the increased i e open circuited Both tests Figure 3 8 should be performed to correlate the result 3 64 MEASUREMENTS IN DBC 3 65 The term dBC means dB Collins and is defined as Section OSCILLATOR hp236A I hp35558 TRANSMISSION NOISE MEASURING SET INDUCTIVE COUPLING 1 1 1 I I I I 1 1 TRANSMISSION NOISE Model 3555B OSCILLATOR hp 236A H hp35558 MEASURING SET CAPACITIVE COUPLING Figure 3 8 Simple Test for Inductive and Capacitive Coupling OdBC 0 775V across any impedance as read on an hp Model 400D AC Vacuum Tube Voltmeter Thus the dBC is strictly a relative term 3 66 Measurements can easily be made in dBC by utilizing the Model 3555B Telephone Test Meter To make these measurements set FUNCTION to 600 and the INPUT switch to TMS BRDG termination required other than 600 ohms must be provided externally and connected across the two binding posts T and R Termination can also be made using a patch cord and any one of the other INPUT jacks since all INPUT jacks are connected in parallel If a 600 ohm termination is to be used the internal termination can be utilized by placing the INPUT switch to the TMS TERM position 3 67 MEASUREMENT PROCEDURES 3 68 Tables 3 3 througH 3 8 liist the step by
105. ing out the front panel controls This table indicates what the results should be for each check along with the specified tolerance A space is provided to enter your results If these spaces are completed for each check they will be of great assistance in making further troubleshooting checks Whenever discrepancy exists between your results and those indicated in column 3 refer to the corrective action column NOTE This table is designed to help locate catastrophic failures your set is only out of the specified tolerances a complete adjustment and calibration procedure should performed as described i 5 34 FUNCTION TROUBLESHOOTING a First determine from the Front Panel Analysis chart Table 5 6 able 5 6 exactly which function is defective Refer to for the probable cause of the malfunction in the FUNCTION switch assembly 5 35 RANGE TROUBLESHOOTING Section V Table 5 7 Function Troubleshooting DEFECTIVE FUNCTION VF Nm CARRIER 75 UNBAL A3K2 135 BAL A1T2 A3K3 A3R22 A3R23 A3L1 A3R24 600 BAL A1T2 600 BAL A1T1 900 BAL A1T1 A3K1 9 ASR20 NG A1R5 thru 1 1 153 L1A B 151 51 DIAL 152 59 First determine from the Front Panel TROUBLESHOOTING Trouble Analysis chart Table 5 9 which range 5 are defective Refer to Table 59 to determine the changes that take place when switching ranges S
106. input level to the set is the algebraic sum of the black dBm meter scale and black RANGE setting For example RANGE is set to 40dBm and the meter indicates 6 3dBm The input level is then 40 6 3 46 3 If the RANGE switch is at 20dBm and the meter indication is 4 7dBm the level is 20 4 7 15 3dBm 3 24 All panel markings corresponding to the proper dBm markings on the RANGE switch and meter face are in black as is the TMS position of the INPUT switch The blue markings correspond to the settings for noise measurements as discussed ian d The response of the meter rectifier circuit is RMS which allows the set to measure the true power of any arbitrary input waveform provided the crest factor does not exceed 4 1 Crest factor is defined as the ratio of the peak value of the waveform to the RMS value of that waveform In most telephonic measurements consideration of this crest factor is not necessary 3 25 The balanced input to the set is achieved through the use of two repeat coils one for voice frequencies from 20Hz to 20kHz and the other for carrier frequencies from 10kHz to 600kHz The maximum high frequency range is achieved through the use of the 75 ohm functions and the 75 ohm jack This input bypasses both input repeat coils thus allowing measurements from 30Hz to 3MHz This high frequency range is limited to 600kHz on the 20 and 30dBm ranges The maximum longitudinal input voltage is 150 volts peak
107. ion Loss Measurement Factory Selected Values 5 16 Range Attenuation and Amplifier Gain 4 4 Replaceable Parts 6 2 Part Number National Stock Number Cross Reference 6 10 SECTION 0 INTRODUCTION 0 1 Scope This manual contains instructions for the operation organizational maintenance and general support maintenance of Audio Level Meter TA 885 U Throughout this manual the equipment is referred to by its commercial designation of Hewlett Packard Model 3555B Transmission and Noise Measuring Set or simply as the 3555B of the manual contains a list of references and appendix B contains the maintenance allocation chart MAC NOTE No direct support maintenance functions are authorized for this equipment 0 2 Indexes of Publications a DA Pam 310 4 Refer to the latest issue of DA Pam 310 4 to determine if there any new editions changes or additional publications pertaining to this equipment b DA Pam 310 7 Refer to DA Pam 310 7 to determine if there are any modification work orders MWO s pertaining to this equipment 0 3 Maintenance Forms Records and Reports a Reports of Maintenance and Unsatisfactory Equipment Department of the Army forms and procedures used for equipment maintenance will be those described by TM 38 750 The Army Maintenance Management System 0 1 b Report of Pac
108. ion are in cabinet checks designed to compare the Model 3555B with its published specifications These checks can be used for incoming inspection periodic maintenance checks and to verify performance after adjustment or repair performance check test card appears at the end of this section which can be used to record the specification performance of your set 5 9 LEVEL ACCURACY CHECKS a Connect only the 654A and 3555B as shown in Figure 5 2 and set the 3555B controls as follows TRANSMISSION amp NOISE MEASURING SET 1 TEST OSCILLATOR 654 83387885 FUNCTION CARRIER 75 UNBAL INPUT TMS TERM RANGE 10dBm Set the 654 frequency to 20 2 IMPEDANCE to 75 UNBAL and adjust the output level for 10dBm If the calibration of the 654 is questionable first connect the output of the 654 through a 75 ohm termination directly to the input of the 3440A 3445A 3555B not connected and measure the voltage This level should be 866mV rms f it is not adjust the 654A amplitude control until it is and note the 654A meter indication for future reference Now that the 654A calibration has been verified disconnect DIGITAL VOLTMETER p3440A 750 FEED THRU TERMINATION Figure 5 2 Level Accuracy Check 3555 100 2 to 600 2 10dBm 10 0 5 10 0 2 0 0 5 0 0 2 10dBm 10 0 5 10 0 2
109. ions appear on scale on the meter with normal response and a two to three minute observation of the pointer fluctuations is made to establish the point at which the pointer appears most of the time disregarding the occasional high peaks For rapidly fluctuating noise such as atmospheric static or switching noise operate the RESPONSE switch to DAMP In this position of the switch the level of the most frequently occurring peaks should be read Noise is specified in dBm decibels above reference noise and the type of filter used is noted for example dBmC meaning C message weighting is used 3 33 The noise metallic level is the algebraic sum of the indication on the blue dBm meter scale and the blue dBm RANGE switch setting For example RANGE is set to 20dBm and the meter indicates 7dBm noise metallic level is 20 7 27dBm The RANGE switch marking indicates the level at the 0dBm mark on the left end of the meter scale 3 34 Occasionally other message circuit weightings such as the older Bell System F1A weighting or the International Telecommunication Union s CCITT psophometric weighting may be required To convert from C message to F1A subtract 6dBm from the C message indication The units for weighting are dBa meaning decibels adjusted To convert from C message to CCITT or psophometric weighting subtract 1dBm from the C message level as read on the black dBm meter scale and RANGE switch setting This
110. k can be used for this function This function does not utilize an input transformer therefore the maximum bandwidth is available on this function This jack accepts a 358 plug 10 DIAL AC MON A set of multiple jacks accepting Western Electric type 310 or 347 plugs 289 dual plugs and a pair of special clip posts marked T and which accept a Western Electric 10111B lineman s handset for the dial and talk operation when the FUNCTION pushbutton marked DIAL BAT is depressed Loop dialing is used and the circuit must supply talk battery When any other FUNCTION pushbutton is depressed the tip and ring of these jacks are connected to the AC MON output of the internal amplifiers for monitoring purposes DC MON Accepts a Western Electric 310 or 347 plug for tip negative and sleeve connections to an external dc recorder Output voltage is proportional to the input voltage on any one setting of the RANGE switch INPUT A set of multiple jacks accepting Western Electric 241 or 289 309 310 and 358 plugs and a pair of binding posts marked T and R for banana plugs spade lugs phone tips or bare wires 3 11 High storage temperature is damaging to dry cells and tends to reduce shelf life Low storage temperature is beneficial to battery life although the battery should be warmed to room temperature prior to use Turning off the set when not in use and consideration of the above factors will maximize battery life The instant turn chara
111. kaging and Handling Deficiencies Fill out and forward DD Form 6 Packaging Improvement Report as prescribed in AR 700 58 NAVSUPINST 4030 29 AFR 71 13 MCO P4030 29A and DLAR 4145 8 c Discrepancy in Shipment Report DISREP SF 361 Fill out and forward Discrepancy in Shipment Report DISREP SF 361 as prescribed in AR 55 38 NAVSUPINST 4610 33B AFR 75 18 MCO P4610 19C and DLAR 4500 15 0 4 Administrative Storage Before placing the TA 885 U in temporary storage 90 days determine the serviceability of the equipment by performing the checks in paragraphs 5 7 throug 0 5 Destruction of Army Electronics Materiel Destruction of Army electronics materiel shall be in accordance with the instructions in TM 750 244 2 0 6 Reporting Equipment Improvement Recommendations EIR If your TA 885 U needs improvement let us know Send us an EIR You the user are the only one who can tell us what you don t like about your equipment Let us know why you don t like the design Tell us why a procedure is hard to perform Put it on an SF 368 Quality Deficiency Report Mail it to Commander US Army Communications and Electronics Materiel Readiness Command ATTN DRSEL ME MQ Fort Monmouth New Jersey 07703 We ll send you a reply 0 7 Items Operable Equipment Audio Level Meter TA 885 U includes the meter with cover and a power cord The power cord is stored inside the cover of the set Section Table 1 1 VOICE FREQ
112. lab Div of Globe Union Inc Milwaukee Wis Commercial Plastics Chicago 11 Cornish Wire The New York N Y Coto Coil Providence Chicago Miniature Lamp Works Chicago Cinch Mfg Co Howard B Jones Div Chicago Dow Corning Corp Midland Mich Electro Motive Mfg Co Inc AUS Willimantic Conn Dialight Corp Brooklyn N Y Indiana General Corp Electronics Div Keasby N J General Instrument Corp Cap Newark N J Drake Mfg Co Harwood Heights Ill Hugh H Inc Philadelphia Pa Gudeman Co Chicago Ill Elastic Stop Nut Corp Union N J Robert M Hadley Co Los Angeles Cal Erie Technological Products Inc Erie Pa Hansen Mfg Co Princeton Ind W W Warper Cmcago Th Helipot Div of Beckman Inst Inc EE Fullerton Cal Hughes Products Division of Hughes Aircraft Newport Beach Amperex Elect Hicksville L I N Y Bradley Semiconductor Corp Q Val pus Carling Electric Inc Hartford Conn Circle Mfg Trenton N J George K Garrett Co Div MSL Industries Philadelphia Federal Screw Products Inc Chicago
113. lent rms detected voltage to drive the meter The meter has shaped pole pieces to provide a linear meter scale both for dBm and dBrn 4 16 DETAILED CIRCUIT DESCRIPTION 4 17 The purpose of the function switch is to set up the input conditions to match the type of measurement being made Impedances can be selected to match the lines to be tested and can be either bridged or terminated Separate transformers are selected for voice frequency and carrier frequency measurements A 40dB attenuator is bridged across the input terminals for longitudinal noise measurements when the Ng pushbutton is depressed The HOLD function places a high inductance holding coil across the input terminals to simulate an off hook condition Each of these functions is described in detail in the following paragraphs a HOLD When the HOLD pushbutton is depressed a high inductance coil Ll is connected across the Model 3555 balanced INPUT terminals if the INPUT TIP 14 AMPLIFIER AC OUTPUT 1 DIAL AC MON RING RING INPUT Model 3555B switch is in the TERM position A bridging HOLD is possible The TERM switch connects the two windings of L1 in series DIAL BAT Sed Figure 4 2 The DIAL BA1 pushbutton serves two purposes First it disconnects the meter from the detector and connects it to the unregulated power supply so that the battery voltage can be monitored Secondly the DIAL AC MON jacks are disconnecte
114. lin Metal Products Corp Ohio Angstrohm Prec Inc No Hollywood Cal Siliconix Sunnyvale Cal McGraw Edison Manchester Power Design Pacific Palo Alto Cal Clevite Corp Semiconductor Div Palo Cal Signetics Corp Sunnyvale Cal Ty Car Mfg Co Inc Holliston Mass TRW Elect Comp Div Des Plaines Chomerics Plainville Mass Curtis Instrument Inc desto t tes PE Mt Kisco N Y Vishay Instruments Inc Malvern E I DuPont and Co Inc Wilmington Del Durant Mfg Milwaukee Wis The Bendix Corp Navigation amp Control Div 22 Teterboro N J Thomas A Edison Industries Div of McGraw Edison West Orange N J Baldwin Park Cal From Handbook Supplements H4 1 Dated January 1970 3555 Manufacturer Address 19644 LRC Electronics Horseheads N 19701 Electra Independence Kansas 20183 General Atronics Corp Philadelphia Pa 21225 Inc Long Island City N Y 21355 Fafnir Bearing Co The New Britian Conn 21520 Fansteel Metallurgical Corp N Chicago 23020 General Reed Metuchen N J 23042 TexscanCorp Indianapolis Ind 23783 British Radio Electronics Ltd Washington DC 24455 G E Lamp Division Nela
115. luded with the instrument notify the nearest Hewlett Packard office and a replacement cord will be provided 2 1 1420 0026 KS 14370 BA 59 482 M 30 VS013 3033 158 30 33 M 202 202 P7830 Hewlett Packard Western Electric Military Eveready Burgess RCA Bright Star Mallory Ray O Vac Sears Wards Wizard Zenith General Marathon National Carbon 2 10 BATTERY 2 11 This set is operated from a single 202 45V dry cell internal battery or an external 48V CO battery when the power selection switch on the side of the case is in the DIAL BAT position Inserting a Western Electric plug into the battery jack disconnects the internal battery See Table 21 Jor batteries suitable for use in this instrument 8120 1351 gt s UL LISTED FOR USE IN THE UNITED STATES OF AMERICA 510 8 4195 Figure 2 1 Power Plugs Section 2 12 INSTALLATION AND REMOVAL OF BATTERY 2 13 To install or replace a battery turn the four 1 4 turn fasteners on the battery cover on the rear of the case counterclockwise to remove the cover Lift off the cover lift the battery out of its recess and unplug the three prong connector 2 14 Reverse the above procedure when installing a new battery 2 15 COVER REMOVAL 2 16 To remove the cover from the instrument release the two spring latches on either side of the instrument then lift cover When replacing the cover first check the la
116. m Range 100Hz to 600kHz 10dBm Range Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range 1MHz to 3MHz 10dBm Range 0dBm Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range CARRIER 135 BAL LEVEL ACCURACY CHECK 1kHz to 600kHz 10dBm Range Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range 10kHz to 300kHz 10dBm Range OdBm Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range 10dBm 0 5dBm 0dBm 0 5dBm 10dBm 0 5dBm 20dBm 0 5dBm 30dBm 0 5dBm 40dBm 0 5dBm 50dBm 0 5dBm 10dBm 0 2dBm 0dBm 0 2dBm 10dBm 0 2dBm 20dBm 0 2dBm 30dBm 0 2dBm 40dBm 0 2dBm 50dBm 0 2dBm 10dBm 0 5dBm 10 of meter indication 0dBm 0 5dBm 10 of meter indication 10dBm 0 5dBm 10 of meter indication 20dBm 0 5dBm 10 of meter indication 30dBm 0 5dBm 10 of meter indication 40dBm 0 5dBm 10 of meter indication 50dBm 0 5dBm 10 of meter indication 10dBm 0 5dBm 0dBm 0 5dBm 10dBm 0 5dBm 20dBm 0 5dBm 30dBm 0 5dBm 40dBm 0 5dBm 50dBm 0 5dBm 10dBm 0 2dBm 0dBm 0 2dBm 10dBm 0 2dBm 20dBm 0 2dBm 30dBm 0 2dBm 40dBm 0 2dBm 50dBm 0 2dBm PERFORMANCE CHECK TEST CARD Cont d CARRIER 600 BAL LEVEL ACCURACY CHECK 1kHz to 150kHz 10dBm Range OdBm Range 10dBm Range 20dBm Range 30dBm Range 40dBm Range 50dBm Range 10kHz to 100 2 10d
117. n N Y Worcester Pressed Aluminum Corp y a Worcester Mass Magnecraft Electric Chicago 11 George A Philbrick Researchers Inc EE Boston Mass Alco Elect Mfg Lawrence Mass Allies Products Corp Diania Fla Continental Connector Corp Woodside N Y Leecraft Mfg Co Inc National Coil Co Vitramon Inc Corp Long Island N Y Sheridan Wyo Bridgeport Conn Bloomfield N J Rolling Meadows Ill Methode Mfg Co Arnold Engineering Co Dage Electric Co Inc Siemon Mfg Co Weckesser Microwave Assoc West Inc Marengo 2 Franklin Ind Wayne Chicago Ill Sunnyvale Cal Code No 96095 96256 96296 96396 96330 96341 96501 96508 96733 96881 97464 91539 97979 97983 98141 98159 98220 98278 98291 98376 98410 98731 98734 98821 98978 99109 99313 99378 99515 99707 99800 99848 99928 99934 99942 99957 Manufacturer Address Hi Q Div of Aerovox Corp Olean N Y Thordarson Meissner Inc Mt Carmel Solar Mfg Los Angeles Cal Microswitch Div of Minn Honeywell Carlton Screw Chicago Ill Microwave Associates Inc Burlington Mass Excel Transformer Co Oakland Cal Xcelite Inc Orchard Park N Y
118. n Gabriel Cal Ucinite Newtonville Mass Waldes Kohinoor Inc Long Island City Y Veeder Root Hartford Conn Wenco Mfg Co Continental Wirt Electronics Corp S ss wiy Wy dre Philadelphia Pa Zierick Mfg Corp New Rochelle N Y Mepco Division of Sessions Clock Co rrr Morristown N J Prestole Corp Toledo Ohio Schnitzer Alloy Products Elizabeth N J Electronic Industries Association Standard tube or semi conductor device any manufacturer Unimax Switch Div Maxon Electronics Re Wallingford United Transformer Corp York N Y Oxford Electric Chicago Bourns Riverside Cal Arco Div of Robertshaw Controls Co EEE ELERE ES Columbus Ohio All Star Products Inc Defiance Ohio Avery Label Monrovia Cal Hammarlund Co Inc Mars Hill Stevens Arnold Inc Boston Mass Dimco Gray Dayton Ohio International Inst Inc Orange Conn Grayhill LaGrange Ill Triad Transformer Corp Venice Cal Winchester Elec Div Litton Ind Inc Oakville Conn Chicago Ill Military Specification International Rectifier Corp Airpax Electronics Inc Cambridge Maryland Barry Controls Div Barry Wright Corp Watertown Mass Carter Pr
119. n arc marked BAT GOOD corresponds to the green DIAL BAT pushbutton for checking the power source The left edge of the arc corresponds to the battery cut off voltage of 24 volts and the right edge meter full scale represents 60 volts which is the maximum voltage that can be used to power the set without internal damage POWER ON OFF Switch turns on all power to the set The set operates from either 115 volts or 230 volts ac the internal 45 volt dry cell battery or from an external office battery supply INPUT Switch Selects TMS either BRDG or TERM for transmission measurements and NOISE either BRDG or TERM for noise measurements For noise measurements the switch must be in Controls Indicators and Connectors either the NOISE BRDG or the NOISE TERM before the NOISE WTG filters can be selected FUNCTION Switch series of interlocking pushbutton switches with the exception of the HOLD switch which is push push type with the following functions a VF Nm 1 HOLD Applies a dc holding bridge across the metallic line for the NG 900 and 600 functions The HOLD pushbutton is the push push type ie push to make and push to break The HOLD function cannot be accomplished when any one of the CARRIER pushbuttons is depressed DIAL BAT Connects the multiple INPUT jacks in parallel with the DIAL AC MON jacks for the dial and talk operation The circuit is arranged for loop dialing and the line under test must supply talk batter
120. n this function f 600 Carrier This function is identical to the 600 Vf Nm function except that the signal is applied to A1T1 and HOLD cannot be accomplished on this function g 135 Carrier The 135 function is identical to the 600 carrier function except that the gain switching in the Input Amplifier is accomplished by one section of the 135 function switch S7 h 75 UNBAL The 75 UNBAL function bypasses the balanced input circuitry and transformer AIT1 and 1 2 Gain switching is performed by one section of this function switch When the 75 UNBAL function is selected the output of the balanced circuitry is disconnected A 75 ohm termination is provided thru the INPUT switch RANGE ATTENUATOR 2 The RANGE attenuator adjusts the input signal This 4 18 4 19 to a suitable level for the Input Amplifier attenuator is composed of four L pads selectable in combinations to provide from to 80dB attenuation Two 30dB pads are selected by A2S1A and A2S1B 20dB pad is selected by 251 and 1098 pad is selected by A2S1D Another section of the RANGE attenuator switch provides gain switching for the Input Amplifier in the 80dBm 70dBm and 60dBm positions Refer to Table 4 1 for more detailed information on range attenuation and amplifier gain 4 20 INPUT AMPLIFIER A3 Schematic No 2 4 21 The purpose of the Input Amplifier is to provide the necessary gain at each setting of the RANGE switch and to
121. nated The terminations when used are provided with a dc blocking capacitor Accidental application of carrier or telegraph battery office battery or ringing voltage will not damage the set The pushbutton marked HOLD bypasses the INPUT switch and terminates the circuit in addition to placing the holding bridge across the line that is connected to the INPUT When the INPUT switch is in either of the NOISE positions weighting filters can be selected by the NOISE WTG switch for noise measurements 3 23 The RANGE switch selects the dBm range of the meter To avoid overloading the set turn the RANGE switch to 309 when connecting a circuit for testing Once the circuit connection is established turn the RANGE switch counterclockwise until an on scale indication is obtained The black dBm marking on the RANGE switch identifies the input level required to deflect the meter to the 0 mark on the black scale The meter uses shaped pole pieces to present linear dBm markings on the scale with marks at 0 1 dBm increments The accuracy and resolution of this type of meter is the same at any point on the scale and it is not necessary to keep the pointer in the upper portion of the scale for maximum accuracy The accuracy of the set is not affected by the position of the set This type of meter will have the pointer off scale to the left 3555 when input signal is present mechanical zero adjust is not required The actual
122. nctional Block Diagram 7 3 7 4 750 RELAY 1350 RELAY 9 2 9000 RELAY 2 METER 4 FROM POWER SUPPLY FROM AMPLIFIER OUT z 55 55 5 5 283 55 ZEE 25 55 8 H3 3 20 uN w 4 6 1 t ur 8 lt zi 25 8 fia aj af al k REMOVE SHORT FOR 150 qe PTT Ej H 2 1 2 ZZZZZ ZZ 2 EET XAI C INPUT SWITCH ASSEMBLY 03555 66507 BOTTOM VIEW ai EMBEDDED WHITE DOT o o A Part 03555 66507 22 o CARRIER Figure 7 2 A1 Function Assembly Schematic and Component Location 7 5 7 6 2 AMPLIFIER DETECTOR 8 SERIES REGULATOR ASSEMBLY 03555 66508 INPUT AMPLIFIER 6 2 RMS hp Part 03555 66509 WEIGHTING FILTERS NOISE 2 30
123. ng the other filters Use the following guide to isolate the trouble to a particular amplifier 1 First be sure that the filters have the correct operating potential applied Check the voltage at the junction of A4R49 and A4C33 to be sure that there is 20 volts 1 volt 2 none of the filters work check A4Q 11 through 4014 3 f the PROG filter does not work but the others do check A6 A4Q5 and A4Q6 4 f C MSG does not work but the others do check A1 A4 and A5 After the trouble has been isolated to an amplifier check the dc potentials indicated on the schematic diagram This will normally isolate the trouble to component If the dc levels are correct but the filter response is out of tolerance no attempt should be made to change the filter characteristics Return the filter to your nearest hp Sales and Service office listed in the back of this manual THE METER AMPLIFIER AND DETECTOR a Inject a 1kHz OdBm signal 775V rms into the 3555B and set the INPUT switch to TMS TERM RANGE to OdBm and the FUNCTION to VF Nm 600 BAL Measure the signal at the input of the meter amplifier XA3 pin 9 The signal level should be 6 2mV rms If not the malfunction is ahead of the meter amplifier refer to troubleshooting tree Figure 5 8 3555 Table 5 8 FUNCTION Switch Resistance Values NOTE Section V The following resistance measurements were made with C1 shorted Be su
124. nstrument and Electronic So Cal Philadelphia Steel and Wire Corp T S Philadelphia Pa American Machine amp Foundry Co Potter 6 Brumfield Div Princeton TRW Electronic Components Div Camden N J General Instrument Corp Rectifier Brooklyn N Y Resistance Products Co Harrisburg Pa Rubbercraft Corp of Calif Torrance Cal Shakeproof Division of Ilinois Tool Works Elgin Ill Sigma So Braintree Mass Signal Indicator Corp New York N Y Struthers Dunn Inc Pitman N J 6 12 Malden Mass Code No 18452 78471 78488 18493 78553 78790 18947 19136 19142 79251 19727 79963 80031 80033 80120 80131 80207 80223 80248 80294 80411 80486 80509 80583 80640 80813 81030 81073 81095 81312 81349 81483 81541 81860 82042 82047 SUAS 82142 82170 82209 82219 82316 82389 82647 82168 82866 82877 82893 83058 83086 83125 83148 83186 83298 83315 83324 83330 83332 83385 83501 83594 83740 83777 83821 83942 84171 84396 84411 Q Manufacturer Thompson Bremer amp Chicago D Tilley Mfg San Francisco Cal Stackpole Carbon Co St Marys Pa Standard Thomson Waltham Mass Tinnerman Products Cleveland Ohio Transformer Engineers Sa
125. ny impedance head phone may be used 3 21 The DIAL BAT function also checks the power source used The green arc on the meter marked BAT GOOD corresponding to the green BAT marking on the pushbutton indicates the range of voltages for proper operation Full scale corresponds to 60 volts and the left end of the arc corresponds to the battery cut off voltage of 24 volts Thus the remaining battery life can be estimated by noting the position of the pointer in the green arc Since the set POWER must be turned ON to perform this check the battery is properly loaded to give a true indication of its condition When operating from the external office battery or AC power the meter monitors this voltage to indicate if it is the correct level to properly power the set The POWER switch turns OFF and ON all power to the set 3 22 The remaining FUNCTIONS are used to set up the input conditions The Ng function will be discussed under the paragraph heading NOISE MEASUREMENTS The impedance of the set is selected by the pushbuttons marked 900 and 600 for voice frequencies and 600 135 and 75 for carrier frequencies The 900 and 600 ohm impedances are normally used for loop plant testing while 600 135 and 75 ohms are usually reserved for carrier system measurements A bridged or terminated condition is determined by the position of the INPUT switch Using this procedure the meter will always indicate in dBm for the impedance selected bridging or termi
126. o uu uu u Performance Checks 5 2 Adjustment and calibration procedure Assembly Em Troubleshooting procedures Factory selected values ice eiecit euer dor e oed Roe 5 15 REPLACEABLE PARTS Rc 6 1 Ordering ied ete tein ra pate 6 4 CIRCUIT DIAGRAMS Lotion 7 1 Functional blocek diagrams uu 7 3 Schematic diagrams D a LAT PER D E 7 5 REFERENCES uu uuu u e Ue Le ee ga MAINTENANCE ALLOCATION det anion Maintenance allocation chart for Meter Audio Level 885 0 Tool and test equipment requirements for Meter Audio Level TA 883 U Remarks Not applicable MANUAL BACKDATING 1 Model 3555 Table Contents LIST OF ILLUSTRATIONS Number Page Number Page 1 11 Model 3555B Transmission and Noise Measuring Set Simplified Peak Detection 4 7 Power Plugs Balanced BNC to 310 Pl
127. o the set as indicated on the recorder is equal to the algebraic sum of the RANGE setting and recorder indication Perform the Noise to ground measurement as described in Table 3 5 Perform the Noise Metallic measurements as described in Table 3 4 Compute the line balance in dB using the results of the above checks Balance dB Nm EXAMPLE 26dBrn 90dBrn 64dBm Noise to ground Noise Metallic Balance in dB NOTE The noise to ground measurement above includes the 40dB correction factor Table 3 8 Transmission Loss Measurement For a transmission loss measurement to be meaningful it should first be determined if there are any extraneous signals present that will affect your measurement To do this connect the measuring set to the circuit and determine if interfering signals are present Levels below 60dB can in most cases be ignored A butt in can be connected to the AC MON jacks to aid in determining the interfering source Establish_a connection like the ones shown in Adjust the oscillator output level for OdBm Measure the level at the receiving end and record this level Insertion loss is equal to the difference between the sending level and the receiving level ignoring any extraneous signals EXAMPLE Sending level Receiving level Insertion loss 20dBm 20dB 3555 Section SECTION IV THEORY OF OPERATION 4 1 INTRODUCTION Set Refer to thi
128. of A3C34 is a convenient place b Turn the set The 3440A 3445A should indicate 20 volts 1 0V c Connect the 400FL AC Voltmeter to the negative side of A3C34 and measure the ripple voltage The maximum allowable ripple is 200uV rms 75 UNBAL CALIBRATION a Connect the 654A and 3440A 3445A as shown in Figure 5 2 and set the 35558 controls as follows 5 18 FUNCTION 75 UNBAL INPUT TMS TERM RANGE 10dBm b Set the 654A frequency to 10 kHz 75 UNBAL and adjust the output level for 866 mV 10 dBm indication on the 3440A 3445A 5 8 5 19 5 20 h Model 3555B Set the 654A meter for a reference indication and be sure to maintain this indication throughout the following procedures unless otherwise instructed Disconnect the 3440A 3445A voltmeter Change the 654A to 50dBm and change the 3555B RANGE switch to 50dBm Disconnect the 3440A 3445A the 11094A termination and the cable Connect the 654A output directly to the 3555B input Adjust A3R43 for OdBm indication on the 3555B meter Change 654A frequency to 3MHz maintaining the reference established on the 654A meter Adjust A3C8 for OdBm indication on the 3555B meter ATTENUATOR CALIBRATION a b Remove the FUNCTION board and replace it with the test board supplied with the set With the equipment and controls set as in the preceding check change the 3555B RANGE to 40dBm and change the 654A attenuato
129. ogy Instrument Corp of California Newbury Park Cal El Monte Cal The following HP Vendors have no number assigned in the latest supplement to the Federal Supply Code for Manufacturers Handbook 000 5 00099 Oakland 000WW California Eastern Lab 000 S K Smith Co Burlington Cal Los Angeles 0000F Malco Tooland Die Los Angeles Calif Hewlett Packard Co Colorado 00002 Willow Leather Products Corp Newark Springs Div Colorado Springs Colorado 00 England 000MM Rubber Eng amp Development Hayward Cal 000 Precision Instrument Comp Van Nuys Cal OOONN D San Jose Cal SUPPLEMENTAL CODE LIST OF MANUFACTURERS Manufacturer Address 12040 National Semicondyctor Corp Danbury Conn 00015 49 Revised May 1910 6 13 From Handbook Supplements H4 1 Dated January 1970 3555 SECTION VII CIRCUIT DIAGRAMS 7 1 INTRODUCTION 7 2 This section of the Manual contains circuit diagrams for the Model 3555B Transmission and Noise Measuring Set The functional block diagram 1 contains signal levels to assist in troubleshooting The schematic diagrams Figures 7 2 througli 7 5 show dc voltage levels which should also aid in locating faulty components 7 3 FUNCTIONAL BLOCK DIAGRAM 7 4 The functional block diagran Fi
130. r PROG weighting filter and a 15kHz FLAT weighting filter These active filters consist of five amplifiers with controlled feedback for waveshaping They are used in combinations to form each of the filters refer to Since all of these amplifiers are Figure 4 4 Simplified Average Detection 4 4 3555 5 08 FREQUENCY 1 t I t 1 1 I 1 1 1 1 1 Ct L3 Figure 4 5 3kHz FLAT Program Weighting Curves 4 5 Section IOOKHz 4 5 6 789 M LEGEND 3KHz FLAT PROGRAM 35558 8 1852 Section PT 1 1 Dn 5 08 TT Figure 4 6 C MSG 1SkHz FLAT Weighting Curves FREQUENCY gun n a au HI UE zu EEL II CEOE ELET a HHH ae
131. r to 40dBm Change the 654A frequency to 100kHz Adjust A2C12 for OdBm indication on the 3555B meter Change the 35558 RANGE switch to 30dBm and change the 654A attenuator to 30dBm Adjust A2C7 for OdBm indication on the 3555B meter Change the 3555B RANGE switch to 20dBm and change the 654A attenuator to 20dBm Adjust A2C4 for 0dBm indication on the 3555B meter Change the 35558 RANGE switch to 10dBm and change the 654A attenuator to 10dBm Adjust A2C1 for 0dBm indication on the 3555B meter Check the frequencies listed in Table 5 2 for the tolerance indicated If any of the checks in Table 5 2 do not meet the indicated tolerances repeat steps b through f FUNCTION CALIBRATION a Remove the test board from the set and install the function board assembly Connect the 654A balanced output to the 3555B balanced input terminals Sed Figure 5 5 Set the 3555B controls as follows Set the 654A frequency to 10kHz and adjust the output attenuators for 5OdBm output level using the 600 BAL output function 3555 5 21 Adjust 15 for 0dBm indication the 3555B meter Change the 654A frequency to 1kHz Change the 3555B FUNCTION switch to VF Nm 600 BAL Compare the 3555B meter indication with the indication in step any difference exists adjust A3R15 to split the difference between these two indications NOTE If the set is being operated from the ac line ground currents may
132. rallel and accept a 310 or a 347 single plug or a 289 dual plug A dial with the impulse springs connected to the tip and ring of a 310 or 347 plug may be used or a lineman s handset such as the Western Electric 1011 may be connected to the two square clip posts for the dialing and talk operation When the FUNCTION pushbutton marked DIAL BAT is depressed the DIAL jacks are connected to the INPUT jacks and a number may be dialed on the line connected to the INPUT jacks The circuit is arranged for loop dial operation and the circuit under test must supply talk battery 3 20 Once the switching equipment has been seized by the dialing operation the connection can be held by depressing the HOLD pushbutton This places a dc bridge consisting of a high impedance retardation coil across the INPUT terminals This coil has negligible effect on measurements of voice frequencies Once any other pushbutton is depressed the AC output of the internal amplifier circuit is returned to the DIAL AC MON jacks for an external head Model 3555 phone which can be used to monitor the noise or tones being measured The 3 6 Model 3555B lineman s hand set which was used for the dialing operation can be used for monitering by leaving it connected to the clip posts The jacks marked 310 will accept a head phone or recorder connected to the tip and ring of a 310 plug or tip and sleeve of a 347 plug The performance of the set is not affected by this output and a
133. rcle around them If the levels or indications in your set do not agree with those on the functional block diagram or troubleshooting tree refer to the paragraph indicated for more detailed information 3555 Section NORMAL INDICATION Meter Indicates OdBm AC Mon Output 2 270mV rms TROUBLESHOOT 1kHz DETECTOR TMS TERM TROUBLESHOOT METER Parag raph 5 38 TRUE TROUBLESHOOT 6 2mV rms FILTERS Paragraph 5 37 FALSE TROUBLESHOOT INPUT AMPLIFIER Paragraph 5 36 Preamplifier Input 2 45mV rms 1kHz TROUBLESHOOT RANGE ATTENUATOR 775 rms INPUT CONDITIONS 1kHz OdBm 775 rms FUNCTION VF Nm 600 BAL INPUT TMS TERM RANGE 0dBm TROUBLESHOOT FUNCTION SWITCH Figure 5 8 Troubleshooting Tree 5 11 Section Model 3555 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 FILTERS FUNCTION CARRIER 20kHz 0dBm 600 BAL Change to 75 RANGE 1kHz 600 BAL LEVEL 10dBm LEVEL 10dBm LEVEL 20dBm Input TMS TERM VF Nm 600 BAL Change INPUT to BRDG RANGE to 10dBm Depress 900 BAL INPUT to TERM RANGE to 0dBm INPUT NOISE TERM NOISE WTG 3kHz FLAT VF Nm 600 BAL Change to C MSG Change to 15kHz FLAT Change
134. re to remove the short after completion of your measurements INPUT JACKS DIAL AC MON JACKS FUNCTION Tip to Ring Tip to Ground Ring to Ground BRDG TERM BRDG TERM BRDG TERM DIAL BAT NG 80 4 kilohms 80 4 kilohms NG HOLD 80 4 kilohms 700 ohms VF Nm 900 BAL 900 ohms DIAL JACKS resistance is 900 BAL HOLD 400 ohms infinite Tip to Ring Tip to Ground and Ring to 600 BAL 600 ohms Ground on all functions 600 BAL HOLD 350 ohms CARRIER 600 BAL 600 ohms 600 BAL HOLD 600 ohms 135 BAL 135 ohms 135 BAL HOLD 135 ohms 75 UNBAL to Ground BRDG 100 kilohms 30dBm thru 30dBm ranges 120 kilohms 40dBm Range 400 kilohms 50dBm thru 80dBm ranges TERM 75 ohms b With a 6 2mV rms signal at pin 9 measure the signal at XA1 pin 6 or at the AC MON jacks This signal should be c 270mV rms signal appears at the AC MON jacks check the detector circuit A3Q11 through A3Q17 270 rms 1100 not check A3Q6 5 39 FACTORY SELECTED VALUES through A3Q10 and associated 5 40 lists the factory selected components using the dc levels indicated components in the Model 3555B along with the purpose inlEigure 7 8 of each Nominal values are shown on the schematic diagrams in Section VII and in the parts list Table 6 1 5 15 Section V Table 5 9 Range Attenuation and Amplifier Gain Model 3555B Table 5 11 Factory Selected Values Attenuator Pads Used Amplifier Gain
135. res a choice of 900 or 600 ohms bridging or terminated for voice frequencies and 600 135 or 75 ohms bridging or terminate for carrier frequencies Noise to ground and noise Metallic may be measured with 3kHz Flat C Message or 1 5kHz Flat weighting HOLD function permits seizing the line while measurements are being made at voice and program frequencies The set is portable and operates from the internal battery office battery or ac power source 3 3 This section of the manual contains all the information necessary in the operation of the 3555B along with description of all controls connectors and indicators 3 4 CONTROLS CONNECTORS AND INDICATORS 3 5 Figure 3 1 3 2 Table 3 1 illustrate and describe the function of all front and side panel controls indicators and connectors 3 6 OPERATION 3 7 operate the Model 35558 refer figure 3 1 and perform the following steps a Before connecting the 3555B to an ac power source insure that the 115 230 volt switch is positioned to indicate the line voltage to be used Some earlier instruments did not have the 115 230 volt selector switch To change these instruments jumper wires must be changed on the power transformer Refer to for a wiring diagram of the two configurations If the set is to be operated from the internal battery or from an external office battery place the AC BAT switch located on the side of the set to the BAT position
136. rip third number indicates narrower strip 924 denotes WHT RED YEL wire Eyelet or standoff terminal standoff may or may not be numbered COMPLETE COMPONENT DESIGNATION Q1 A2Q1 R1 A2A1R1 41 41 Assembly Number includes 241 subassembly monid oh Assembly A2 Destination of wire Assembly Jack J3 J2 Pin 4 A3J3 4 Pin may or may not be numbered T Female pin connector on WHT RED wire pin connector STD A 0794 Section VII Model 3555B SCHEMATIC 5 PARTIAL REFERENCE DESIGNATIONS ARE SHOWN PREFIX WITH ASSEMBLY OR SUBASSEMBLY DESIGNATION S OR BOTH FOR COMPLETE DESIGNATION COMPONENT VALUES ARE SHOWN AS FOLLOWS UNLESS OTHERWISE NOTED RESISTANCE IN OHMS CAPACITANCE IN MICROFARADS DENOTES ASSEMBLY CIRCUIT GROUND ala DENOTES CHASSIS CIRCUIT GROUND DENOTES POWER LINE GROUND DENOTES ASSEMBLY DENOTES MAIN SIGNAL PATH DENOTES FRONT PANEL MARKING 51 Ca clc WI EE DENOTES SCREWDRIVER ADJUST DENOTES SIDE AND REAR PANEL MARKING 924 DENOTES WIRE COLOR COLOR CODE SAME AS RESISTOR COLOR CODE FIRST NUMBER IDENTIFIES BASE COLOR SECOND NUMBER IDENTIFIES WIDER STRIP THIRD NUMBER IDENTIFIES NARROWER STRIP 924 WHITE RED YELLOW AVERAGE VALUE SHOWN OPTIMUM VALUE SELECTED AT FACTORY TRANSISTORS ARE ALL CONNECTED CIRCUIT BOARD 5 CONFIGURATION
137. rns off No current will flow through the meter the positive half cycle A3Q14 turns off and A3Q17 turns on The current paths for the average detector are shown in Figure 4 7 Simplified Peak Detection 4 7 Section 4 35 Now consider the peak detection Sed Figure When 14 is turned on and A3Q17 is turned off no current flows through the meter from the peak detector When A3Q14 is turned off and A3Q17 is turned on the current path is as shown by the heavy lines in Figure 4 7 Diodes A3CR12 and A3CR13 are included to offset the junction drop of 5 and 16 respectively 4 36 When the average detection and the peak detector are combined in the proper proportion an equivalent rms response is produced The advantage of this type of rms detection is fast response 4 37 POWER SUPPLY AND SERIES REGULATOR Schematic No 4 4 38 The 3555B can be operated from 115V or 230V ac the internal 48V dry cell battery or from a central office battery tip negative When operating from an ac source power is applied through transformer and the AC BAT switch S1 to the rectifier CR1 This rectified 4 8 Model 3555B voltage is filtered by C2 before being applied to the series regulator through J2 S3 CR1 and cable W1 4 39 The regulator is of the conventional series type with A3Q19 acting as the sensing element and 20 as the reference Changes in the output level are amplified by differential
138. rp Cleveland Ohio 71002 Radio New York N Y 71034 Electric 71041 Boston Gear Works Div of Murray of Texas Quincey Mass 71218 Bud Radio Inc Willoughby Ohio 71279 Cambridge Thermionics Corp Cambridge Mass 11286 1 Fastener Corp Paramus N J 71313 Cardwell Condenser Corp Lindenhurst L I N Y 71400 Bussmann Mfg Div of McGraw Edison Co St Louis Mo 71436 Chicago Condenser Corp Chicago 71447 Calif Spring Co Pico Rivera Cal 71450 5 DP Elkhart Ind 71468 ITT Cannon Electric Inc Los Angeles Cal 71471 Cinema Div Burbank Cal 00015 49 Revised May 1970 CODE LIST OF MANUFACTURERS Continued Code No 71482 71590 11616 71700 71707 71744 71785 71984 12136 72619 72656 12699 12765 12825 12928 12962 12964 72982 73061 13916 73138 13293 73445 13506 13559 73586 73682 73734 73743 73793 73846 73899 73905 13957 14216 74455 14861 74868 74970 75042 15263 15378 75382 75818 75915 76005 76210 76433 16487 16493 16530 76545 76703 76854 77068 17015 11221 11252 77342 77630 77638 77764 77969 78189 78277 78283 18290 Manufacturer Address Chicago Centra
139. s figure for the following block diagram 4 2 The Model 3555B Transmission and Noise description Measuring Set is a special measuring set designed for 4 9 The input signal is first applied to the uses in testing telecommunications equipment Inputs between 90dBm and 30dBm full scale can be selected in twelve ranges for level measurements correspond to the black markings on the meter scale and the RANGE switch Noise measurements between OdBrn and 120dBrn full scale can be made selectable in twelve ranges and corresponds to the blue markings on the meter scale and RANGE switch When measuring rapidly fluctuating noises a damping circuit can be inserted by the RESPONSE switch 4 3 Impedances of 75 135 and 600 ohms terminated or bridging can be selected for carrier level measurements The 135 and 600 ohm functions can be either balanced or unbalanced while the 75 ohm function is unbalanced only For voice frequencies impedances of 600 and 900 ohms are provided These impedances are selectable by the pushbutton FUNCTION switch and can be terminated or bridging balanced or unbalanced 4 4 noise to ground Ng function is included to permit measurement of longitudinal noise When the Ng pushbutton is depressed a 404 attenuator is placed across the INPUT terminals 4 5 The HOLD function places high inductance holding coil across the INPUT terminals to simulate an off hook condition while measurements are being made The
140. ss 54294 Shalleross Mfg Co Selma 5026 Simpson Electric Co Chicago Ill 55933 Sonotone Corp Elmsford N Y 55938 Raytheon Co Commercial Apparatus amp System Div So Norwalk Conn 56131 Spaulding Fibre Ca Inc Tonawanda 56289 Sprague Electric North Adams Mass 58474 Superior Bristol Conn 59446 Telex Corp Tulsa Okla 59130 Thomas 6 Betts Elizabeth N J 60741 Triplett Electrical Inst Bluffton Ohio 61775 Union Switch and Signal Div of Westinghouse Air Brake Pittsburgh 62119 Universal Electric Co Owosso Mich 63743 Ward Leonard Electric Co Mt Vernon N Y 64959 Western Electric Co Inc New York N Y 65092 Weston Inst Inc Weston Newark Newark N J 66295 Wittek Mig Chicago 66346 Minnesota Mining amp Mfg Co Revere Mincom Div St Paul Minn 70276 Allen Mfg Hartford Conn 70309 Allied Control York N Y 70318 Allmetal Screw Product Co Inc Garden City N Y 70417 Amplex Div of Chrysler Corp Detroit Mich 70485 Atlantic India Rubber Works Inc Chicago 10563 Amperite Co Inc Union City N J 70674 ADC Products Inc Minneapolis Minn 70903 Belden Mfg Chicago 10998 Bird Electric Co
141. t 10uF 50 10 150 vdcw 56289 30D106F150DD2 DSM C4 0121 4105 3 C var 9 35pF 72982 538 00694D C5 0160 0205 2 C fxd mica 10pF 5 72136 RDM15C100J5S C6 0160 2206 1 C fxd mica 160pF 5 72136 RDM15F161J3C C7 0121 0105 C var 9 35pF 72982 53830694D 0140 0204 1 fxd mica 47pF 5 72136 DM15E470J0500W1CR C9 0140 0193 1 C fxd mica 82pF 5 72136 RDM15E820J3C C10 0160 0763 1 C fxd mica 5pF 1096 14655 RDM15C050K5S obd R1 0698 0090 2 fxd met flm 464 ohms 1 1 2W 91637 MFF 1 2 T 1 obd R2 0811 2846 2 fxd ww 300 ohms 1 1 2W hp R3 0684 2211 3 fxd comp 220 ohms 10 1 4W 01121 CB2211 R4 0811 2847 2 fxd ww 67 5 ohms 1 1 2W hp R5 R6 0698 3499 2 fxd met flm 40 2 kilohms 1 1 8W 91637 MF 1 10 32 obd R7 0698 4508 1 fxd met flm 78 7 kilohms 1 1 8W 14674 C4 obd R8 0698 4467 1 fxd met 1 05 kilohms 1 1 8W 91637 MF 1 10 32 obd R9 0698 0090 fxd met flm 464 ohms 1 1 2W 91637 MFF 1 2 T 1 obd R10 0811 2846 fxd ww 300 ohms 1 1 2W hp R11 0684 2211 fxd comp 220 ohms 10 1 4W 01121 CB2211 R12 0684 4711 1 fxd comp 470 ohms 10 1 4W 01121 CB4711 R13 0811 2794 1 R fxd prec ww 25 kilohms 596 hp R14 0684 2211 fxd comp 220 ohms 10 1 4W 01121 CB2211 R15 0757 0472 3 fxd met 200 kilohms 1 1 8W 75042 CEA obd R16 0811 2847 fxd ww 67 5 ohms 1 1 2W hp R17 0683 1505 1 fxd 15 ohms 5 1 4W 01121 CB1505 51 3100 1793 1 Switch Ass y pushbutton
142. tches for released position then place cover in position for latching The power cord is stored inside the cover by wrapping it around the retainer fastened inside the cover CAUTION DO NOT FORCE COVER INTO PLACE THERE IS A PROJECTION ON THE COVER WHICH TURNS THE POWER SWITCH TO THE OFF 2 2 Model 355B POSITION TO PRESERVE BATTERY LIFE IF THIS IS NOT BINDING THE COVER FITS EASILY INTO PLACE 2 17 REPACKAGING FOR SHIPMENT 2 18 The following is a general guide for repackaging at instrument for shipment If you have any questions contact your local Sales and Service Office See Appendix for locations a Place instrument in original container if available If not available one can be purchased from your nearest hp Sales and Service Office b Wrap instrument in heavy paper or plastic before placing in inner container Use plenty of packing material around all sides of instrument d Use a heavy carton or wooden box to house the instrument and inner container and use strong tape or metal bands to seal the shipping container e Mark shipping container with Instrument or Fragile Delicate Section lll Model 3555B SECTION INSTRUCTIONS 3 1 INTRODUCTION 3 2 The Model 3555 Transmission and Noise Measuring Set is an extremely versatile transmission and noise measuring set which satisfies many of the requirements in testing telecommunications equipment The 3555B featu
143. the 135 BAL function to a 150 BAL Table 5 1 Required Test Equipment TYPE REQUIRED CHARACTERISTICS MODEL Oscillator Frequency Range 20Hz to 3MHz hp 654A Levels 80dBm to 30dBm Accuracy 0 1 598 Am 30V Transfomer Linematchng hp 11004A Voltmeter diqital Function AC and DG Accuracy 1 Amplifier Voltage gain 20 dB hp 3440A 3445A hp 467A 20 peak at 0 5 peak Accuracy 2 hp 11048B hp 11094A Cabes 576 ohms 1 1 Resistors 875 ohms 1 1 300 ohms 0 1 4 600 ohms 0 1 4 135 ohms 0 1 4 75 ohms 0 1 4 900 ohms 0 1 150 ohms 1 2 100 kilohms 1 1 5 1 Trompeter AD 1W 06984598 Use 825 ohm 0757 0731 49 9 ohm 069844110 in series 0698 6295 0698 7408 0698 7364 0698 7363 Use 600 300 series 0 1 0698 6774 0757 0465 Section V Model 3555B SCHEMATIC Figure 5 1 Balanced BNC to 310 Plug function remove or clip the shorting bar from across A1 R17 sed Figure 7 2 b Remove the 150 BAL decal from the small envelope supplied with the set and stick it over the existing 135 BAL decal c Adjust the 150 function as described in in this manual 5 7 CHECKS 5 8 The performance checks presented in this sect
144. tiona NATO Stock Number This column lists the National NATO stock number of the specific tool or test equipment e Tool Number This column lists the manufacturer s part number of the tool followed by the Federal Supply Code for manufacturers 5 digit parentheses B 5 Remarks Sec IV a Reference Code This code refers to the appropriate item section IT column 6 The numbers indicate the applicable tool or test b Remarks This column provides the equipment for the maintenance functions required explanatory information necessary to clarify items appearing Next printed B 2 11 6625 2779 14 amp SECTION MAINTENANCE ALLOCATION CHART FOR AUDIO LEVEL METER TA 885 U 1 2 3 4 5 6 MAINTENANCE CATEGORY GROUP MAINTENANCE TOOLS AND NUMBER COMPONENT ASSEMBLY FUNCTION C 5 00 AUDIO LEVEL METER 885 Inspect 0 5 7 HP 3555B Test 0 5 1 thru 7 Service 0 8 1 thru 7 Repair 1 2 1 thru 7 Overhaul 2 0 1 thru 7 B 3 11 7725 2779 148 SECTION 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 OSCILLATOR SG 1128 U HP 654A 6625 00 450 7590 OSCILLATOR AN URM 127 6625 00 783 5965 TRANSFORMER LINE MATCHING MX 8385 U 6625 00 567 5837 MULTIMETER AN USM 451 6625 01 060
145. to PROG INPUT TMS TERM FUNCTION CARRIER 600 BAL Change INPUT to BRDG RANGE to 10dBm Depress 135 BAL RANGE to 20dBm Change INPUT to TERM RANGE to 0dBm UNBAL INPUT TMS TERM FUNCTION 75 UNBAL RANGE 0dBm Change INPUT to BRDG RANGE to 10dBm Change INPUT back to TERM RANGE to 0dBm Change RANGE to 10dBm FUNCTION VF Nm 600 BAL Change RANGE to 10dBm Change RANGE to 20dBm OdBm 0 2dBm 6dBm 0 2dBm 4 2 0 2dBm 0 1 5dBm 0 2dBm OdBm OdBm 0 2dBm OdBm 0 2dBm OdBrn 0 2dBm 1dBm OdBm 6dBm 0 5dBm 12 6dBm 0 5dBm 2 2dBm 0 5dBm OdBm 0 2dBm 6dBm 0 2dBm OdBm 0 2dBm 10dBm 0 2dBm 10dBm 0 2dBm 20dBm 0 2dBm Refer td Paragraph 5 34 Refer td Paragraph 5 34 Refer td Paragraph 5 34 Refer td Paragraph 5 34 Refer td Paragraph 5 37 Refer td Paragraph 5 37 Refer td Paragraph 5 37 Refer td Paragraph 5 37 Refer td Paragraph 5 37 Refer to Paragraph 5 34 Refer td Paragraph 5 34 Refer td Paragraph 5 34 Refer td Paragraph 5 34 Refer td Paragraph 5 34 Refer to Table 5 8 Refer to Table 5 8 5 35 See Paragraph 5 35 Paragraph 5 35 5 12 3555 Section Table 5 6 Front Panel Trouble Analysis 3555B SHOULD INDICATE SET ACTUALLY CORRECTIVE INPUT CONDITIONS FUNCTION RANGE METER INDICATES ACTION LEVEL 30dBm Change RANGE to 30dBm 30dBm
146. u CR7 1901 0040 11 Diode Si 30 wiv 2pF 30mA 2ns 07263 FDG1088 CR8 1902 0761 3 Diode zener 6 2V 5 400mW 7 5mA 04713 Type 1N821 CR9 1902 3030 Diode zener 3 01V 5 400mW 20mA 04713 5210939 32 1901 0040 Diode Si 30 2 30mA 2ns 07263 FDG1OB8 CR11 1902 3030 Diode zener 3 01V 5 400mW 20mA 04713 SZ10939 32 CR12 CR13 1901 0040 Diode Si 30 wiv 2pF 30mA 2ns 07263 FDG1088 CR14 1902 0761 Diode zener 6 2V 5 400mW 7 5 04713 Type 1N821 CR15 CR16 1901 0040 Diode Si 30 wiv 2pF 30mA 2ns 07263 FDG1088 CR17 1901 0025 7 Diode Si 100 wiv 12pF 10mA 24446 SS410 CR18 CR19 1901 0040 Diode Si 30 wiv 2pF 30mA 2ns 07263 FDG10O88 6 3 Section 3555 Table 6 1 Replaceable Parts Cont d REFERENCE hp TQ DESCRIPTION MFR MFR PART NO DESIGNATOR PART NO Cont d CR20 1902 1275 Diode zener 6 2 5 400mW 7 5mA 04713 Type 1N821 CR21 1901 0040 Diode Si 30 wiv 2pF 30mA 2ns 07263 FDG1088 K1 thru K3 0490 0780 3 Relay Ass y reed hp 0490 0778 3 Reeds 95348 MR5830 L1 9100 1637 1 Inductor fxd 120uH 5 82142 15 1315 14J Q1 1853 0086 7 TSTR Si PNP 2N5087 04713 SPS 3322 Q2 Q3 1853 0036 9 TSTR Si PNP 2N3906 04713 SPS 3612 Q4 1854 0215 3 TSTR Si NPN 2N3904 04713 SPS 3611 Q5 thru Q8 1853 0036 TSTR Si PNP 2N3906 04713 SPS 3612 Q9 1854 0215 TSTR Si NPN 2N3904 04713 SPS 3611 Q10 1853 0036 TSTR Si PNP 2N3906 04713 SPS 3612 Q11 1855 0057 1 TSTR Si FET N channel Type A 04713 SS 3651 Q12 1
147. ug 5 2 3 1 Front Panel Controls Indicators Level Accuracy Check 5 2 and Connectors 20dBm and 30dBm Level Side Panel Controls and Connectors Accuracy Impedance Matching 35558 to Recorder Return Loss Test Set Up Recorder Compatibility Chart Filter Response Test Set Up Simplified Send Receive Test Set Up Bridging Loss Test Set Up Typical Test Set Up for Measuring Input Balance Test 5 Insertion LOSS Troubleshooting Test Set Up for Measuring Functional Block Crosstalk Coupling Loss A1 Function Assembly Schematic and 3 8 Simple Test for Inductive and Component Location 7 5 7 6 Capacitive 2 Range Attenuator Input Simplified Block Amplifier Schematic and Component Simplified DIAL BAT Function LOCUM Simplified NG
148. using a small pointed object if the set is to be operated from the ac line place the AC BAT switch to the AC position For operation from a 24 or 48 office battery connect a patch cord with a Western Electric 310 plug to the battery jack on the side of the case and then connect the cord to the office battery on the test board or bay Inserting the plug disconnects the internal battery The office battery is arranged for 48V or 24V 2V with the negative terminal of the battery connected to the tip and the ground terminal connected to the sleeve Current consumption by the 3555B is approximately 15mA WARNING DURING BATTERY OPERATION THE BINDING POST MUST BE CONNECTED TO EARTH GROUND CAUTION THE CORD MUST BE CONNECTED TO THE MEASURING SET BATTERY JACK FIRST AND THEN PLUGGED INTO THE BATTERY SUPPLY TO AVOID SHORTING THE OFFICE BATTERY TO GROUND c Turn the POWER switch to ON and depress the DIAL BAT pushbutton on the FUNCTION switch The meter pointer should indicate in the BAT GOOD area indicating that the battery condition is good if the set is being operated from the internal battery The meter will also monitor the ac supply voltage or the external office battery voltage providing an indication of low voltage should it exist The voltage should cause meter deflection above the lower end of the green BAT GOOD area for proper set operation 3 8 BATTERY 3 9 The internal dry cell battery has a voltage range between
149. will give the noise level in dBm which is acceptable for psophometric measurements Section 3 35 identifying the source noise the DIAL AC MON jacks can be used with a monitoring receiver to listen to the noise which will have approximately the same quality as that heard by subscriber Particular types of noise like power line induction switching noise atmospheric static crosstalk or random noise may be identified by this listening test To aid in bringing up the level of the lower frequency power line noise the 3kHz flat weighting is used A substantial increase in meter indication with the 3kHz flat weighting indicates the presence of low frequency noise and it will also sound louder in the monitoring headphone 3 36 In some cases recording of the noise during a busy period is necessary The recorder connections and operation is discussed Paragraph 3 27 The calibration should be done using the dBm scale rather than the dBm scale and it should be noted that the RESPONSE switch also damps the recorder 3 37 Noise to ground measurements are made by a special input circuit arrangement which is used when either the Ng or Ng HOLD pushbutton is depressed Dial and talk may be accomplished on the metallic circuit and the metallic connection held by using the Ng HOLD pushbutton It is necessary to establish a good earth or system ground and connect it to the black binding post marked G The noise to groun
150. y Connects the meter circuit and a load to the internal power supply to check the condition of the battery ac power or external office battery as indicated on the green meter scale POWER 7 must be ON for the battery test 3 NG Selects the noise to ground input circuits for measuring longitudinal noise Attenuation of 40dB is inserted by this circuit Earth ground should be connected to the black G binding post 1 4 900 Selects the input circuitry balanced 900 ohm circuits This function selects a low frequency transformer for voice frequencies Response of this transformer is 20Hz to 20kHz 5 600 Selects the input circuitry for balanced 600 ohm circuits A low frequency transformer is selected for this function Carrier 1 600 Selects the input circuitry for balanced 600 ohm circuits high frequency transformer is selected for this function Response this transformer is 1 2 to 600kHz The HOLD function is not operative in any of the carrier functions Section 3555 48V Figure 3 2 Side Panel Controls and Connectors 3 4 3555 Section Table 3 1 Front Side Rear Panel Controls Indicators and Connectors Cont d 2 135 Selects the input circuitry for 135 ohm balanced circuits A high frequency transformer is selected for this function 75 Selects the input circuitry for 75 ohm unbalanced operation Only the 75 ohm jac

HP TM 11-6625-2779-14&P User's Manual

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HP TM 11-6625-2779-14&amp;P User's Manual

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HP TM 11-6625-2779-14&P User's Manual