Home

Tektronix Video Game Keyboard 502 User's Manual

1. 502 DIGITAL MULTIMETER INSTRUCTION MANUAL Tektronix Inc Box 500 Beaverton Oregon 97005 Serial Number WARRANTY All TEKTRONIX instruments are warranted against defective materials and workmanship for one year Any questions with respect to the warranty should be taken up with your TEKTRONIX Field Engineer or representative All requests for repairs and replacement parts should be directed to the TEKTRONIX Field Office or representative in your area This will assure you the fastest possible service Please include the instrument Type Number or Part Number and Serial Number with all requests for parts or service Specifications and price change privileges reserved Copyright 1974 by Tektronix Inc Beaverton Oregon Printed in the United States of America All rights reserved Contents of this publication may not be reproduced in any form without permission of Tektronix Inc U S A and foreign TEKTRONIX products covered by U S and foreign patents and or patents pending TEKTRONIX is a registered trademark of Tektronix Inc TABLE OF CONTENTS Page SECTION 1 OPERATING INSTRUCTIONS Introduction 1 1 Instrument Description 1 1 Installation and Removal 1 1 Operating Considerations 1 2 Input Connections 1 2 Functions Available at Rear Connector 1 2 Sine Wave Response 1 3 Temperature Measurements 1 3 Making Measurements 1 4 DC Voltage Measurements 1 4 DC Current Measurements 1 4
2. Fig amp Index Tektronix Serial Model o Mfr No Part No Dscont QY 12345 Name amp Description Code Mfr Part Number 36 200 1743 00 1 COVER CAM SW 6 200 DA 18 32 ELEM 80009 200 1743 00 ATTACHING PARTS 37 211 0008 00 8 SCREW MACHINE 4 40 X 0 25 INCH PNH STL 83385 OBD 38 210 0004 00 B MASHER LOCK INTL O 12 ID X 0 26 0D STL 78189 1204 00 00 0541 ii ace 39 210 0406 00 4 NUT PLAIN HEX 4 40 X 0 188 INCH BRS 73743 2 12161 402 40 407 1199 00 1 BRACKET COVER 80009 407 1199 00 41 376 0008 00 1 CPLG SHAFT RGD 80009 376 0008 00 213 0005 00 2 SETSCREW 8 32 X 1 25 INCH HEX SOC STL 74445 OBD 42 210 0406 00 4 NUT PLAIN HEX 4 40 X 0 188 INCH BRS 73743 2 12161 402 43 214 1139 03 1 SPRING FLAT RED COLORED 80009 214 1139 03 214 1139 02 1 SPRING FLAT GREEN COLORED 80009 214 1139 02 44 214 1127 00 2 ROLLER DETENT 0 125 DIA X 0 125 INCH L 80009 214 1127 00 45 401 0081 02 1 BEARING CAM SW FRONT 80009 401 0081 02 ATTACHING PARTS 46 354 0391 00 1 RING RETAINING 0 395 FREE ID X 0 025 STL 97464 3100 43 CD xr Sitges 47 105 0642 00 1 ACTUATOR CAM SW TIME CM REAR 80009 105 0642 00 48 210 0406 00 4 NUT PLAIN HEX 4 40 X 0 188 INCH BRS 73743 2 12161 402 49 401 0115 00 1 BEARING CAM SW CENTER 80009 401 0115 00 50 210 0406 00 4 NUT PLAIN HEX 4 40 X 0 188 INCH BRS 73743 2 12161 402 51 214 1139 03 1 SPRING FLAT RED COLORED 80009 214 1139 03 214 1139 02 1 SP
3. CIRCUIT SOC HEXAGONAL SOCKET COMP COMPOSITION HLCPS HELICAL COMPRESSION CONN CONNECTOR HLEXT HELICAL EXTENSION cov COVER HIGH VOLTAGE CPLG COUPLING INTEGRATED CIRCUIT CRT CATHODE RAY TUBE 10 INSIDE DIAMETER DEG DEGREE IDENT IDENTIFICATION DWR DRAWER IMPLR IMPELLER N INCH sE SINGLE END INCAND INCANDESCENT SECTION INSUL INSULATOR SEMICOND SEMICONDUCTOR INTL INTERNAL SHLD SHIELD LPHLDR LAMPHOLDER SHLOR SHOULDERED MACH MACHINE SKT SOCKET MECH MECHANICAL St SLIDE MTG MOUNTING SLFLKG SELF LOCKING NIP NIPPLE SLVG SLEEVING NON WIRE NOT WIRE WOUND SPR SPRING ORDER BY DESCRIPTION 50 SQUARE 00 OUTSIDE DIAMETER SST STAINLESS STEEL OVH OVAL HEAD STL STEEL PH BRZ PHOSPHOR BRONZE sw SWITCH PL PLAIN or PLATE T TUBE PLSTC PLASTIC TERM TERMINAL PN PART NUMBER THO THREAD PAN HEAD THK THICK PWR POWER TNSN TENSION RCPT RECEPTACLE TPG TAPPING RES RESISTOR TRH TRUSS HEAD RGD RIGID v VOLTAGE RLF RELIEF VAR VARIABLE RTNR RETAINER w WITH SCH SOCKET HEAD WSHA WASHER SCOPE OSCILLOSCOPE XFMA TRANSFORMER SCR SCREW XSTR TRANSISTOR 51 Mechanical Parts List DM 502 MFR CODE 00008 0000C 00779 01295 05820 08261 22526 23499 45722 58474 71590 73743 74445 77250 78189 80009 82647 83385 97464 5 2 CROSS INDEX MFR CODE NUMBER TO MANUFACTURER MANUFACTURER LEMO USA GETTIG ENGINEERING AND MANUFACTURING CO AMP INC TEXAS INSTRUMENTS INC SE
4. e e INDICATES CONTACT ele O CLOSED e je e lefelelole O O O O O O O DM 502 REV 1974 Section 5 DM 502 REPLACEABLE MECHANICAL PARTS PARTS ORDERING INFORMATION Replacement parts are available from or through your local Tektronix Inc Field Office or representative Changes to Tektronix instruments are sometimes made to accommodate improved components as they become available and to give you the benefit of the latest circuit improvements developed in our engineering department It is therefore important when ordering parts to include the following information in your order Part number instrument type or number serial number and modification number if applicable If a you have ordered has been replaced with a new or improved part your local Tektronix Inc Field Office or representative will contact you concerning any change in part number Change information if any is located at the rear of this manual SPECIAL NOTES AND SYMBOLS X000 first added at this serial number 00x Part removed after this serial number FIGURE AND INDEX NUMBERS Items in this section are referenced by figure and index numbers to the illustrations INDENTATION SYSTEM This mechanical parts list is indented to indicate item relationships Following is an example of the indentation system used in the description column 12345 Name amp
5. 97 C198 199 T vie 100K Acre v
6. 8329 DI 0345 CR240 4 R170 F5 9330 DI 0420 16 290 2 1 970 sod lt RITA RIS no 2504 C75 33uF 953k 204B 3 246 SEE PARTS LIST FOR EARLIER Rigo VALUES AND SERIAL NUMBER RANGES OF PARTS MARKED WITH BLUE R224 8A Jj 24 9K He AC COMP Jis V x SEE D FOR sio LOCATED Rees SWITEHING LOG 120 nese R271 R277 R279 665 PIIR 1 876 OFFSET seo 500 gt 910 45 MI we 1 248 Al MAIN BOARD REV B 1974 ATTENUATORS CONVERSION CIRCUITS 8 8 12 74 5V eme le f 5 14 4 8 m j TO R203 1345 SNe ev 22 I nag 190i i 12 4 49 la 8 P3507 2 e Mo 4 e 9350 n sby 15 e 5 8 9V U345C 8355 N eso 746 Fun 1 g rider U335 sk cono Rago R29 M 100K 15 TO woe E E TO 510 45 5 3 FROM 315 55 65 22208 7 w290 A D ZERO NOTE USED ONLY WITH OPTION2 4 A 05350
7. AC Voltage Current and Resistance Measurements 1 5 Decibel Measurements 1 5 Temperature Measurements 1 5 Using a Transistor as a Temperature Sensing Device 1 5 Accurate Current Source 1 6 Specifications 1 6 SECTION 2 THEORY OF OPERATION Introduction 2 1 Attenuator and Input Switching 2 1 AC Converter 2 1 DB Converter 2 1 Ohms Converter 2 2 Temperature Measurement Circuitry 2 2 Clock 2 3 Analog To Digital Converter 2 3 Display 2 5 Power Supplies 2 5 SECTION 3 ELECTRICAL REPLACEABLE PARTS LIST SECTION 4 SERVICE INFORMATION Internal Adjustment Procedure Rear Interface Connector Assignments Rear Interface Connector Wire Locations Front Panel Controls and Connectors Block Diagram Parts Location Grid Attenuators and Conversion Circuits Schematic Integrator A D Converter and Display Schematic Power Supply and Switch Logic Schematic SECTION 5 MECHANICAL REPLACEABLE PARTS LIST Accessories Repackaging Exploded View CHANGE INFORMATION REV A OCT 1974 i TEKTRONIX DM 502 METER DM 502 Section 1 DM 502 OPERATING INSTRUCTIONS INTRODUCTION Instrument Description The DM 502 Digital Multimeter measures dc and ac voltage and current dBm dBV resistance and temperature The ac functions are average responding and rms calibrated for sine waves A single front panel control selects all ranges A front panel pushbutton selects dB readout of ac functions in lieu of voltage or curre
8. C even while using other functions of the DM 502 To avoid a momentary scale change when a recorder or other device is connected to these terminals avoid switching through the F position The DM 502 may be hard wired in either the C or F range independent of the range function switch setting To hard wire in the F range connect a jumper as shown in Fig 1 2 To hard wire in C lift either end of R285 as shown in Fig 1 2 MAKING MEASUREMENTS With the DM 502 properly installed in the power module allow twenty minutes warmup time for operation to specified accuracy When the value of the quantity being measured is unknown selectthe highest range first Decrease the range setting until the display blinks in dicating over range Then increase the range switch to the next higher position This method obtains maximum resolution Resolution of the DM 502 is 0 05 of full scale setting except temperature which is 0 1 Do not exceed the maximum voltage ratings With the range function Switch in the 1 K DC VOLTS or 500 AC VOLTS position internal damage may result before overrange is indicated DC Voltage Measurements Select an appropriate full range dc voltage position with the range function switch Apply the voltage to be measured to the INPUT binding posts Observe the maximum voltage ratings as indicated on the front panel The readout displays a if the HI input is positive with respect to the LO input A is displayed i
9. Description Assembly and or Component Attaching parts for Assembly and or Component Detail Part of Assembly and or Component Attaching parts for Detail Part Parts of Detail Part Attaching parts for Parts of Detail Part Attaching Parts always appear in the same indentation as the item it mounts while the detail parts are indented to the right Indented items are part of and included with the next higher indentation The separation symbol indicates the end of attaching parts Attaching parts must be purchased separately unless otherwise specified ITEM NAME In the Parts List an Item Name is separated from the description by a colon Because of space limitations an Item Name may sometimes appear as incomplete For further Item Name identification the U S Federal Cataloging Handbook H6 1 can be utilized where possible ABBREVIATIONS INCH ELCTRN ELECTRON NUMBER SIZE ELEC ELECTRICAL ACTUATOR ELCTLT ELECTROLYTIC ADAPTER ELEM ELEMENT ALIGN ALIGNMENT EPL ELECTRICAL PARTS LIST AL ALUMINUM EOPT EQUIPMENT ASSEM ASSEMBLED EXT EXTERNAL ASSY ASSEMBLY FIL FILLISTER HEAD ATTEN ATTENUATOR FLEX FLEXIBLE AWG AMERICAN WIRE GAGE FLH FLAT HEAD 80 BOARD FLTR FILTER BRKT BRACKET FR FRAME or FRONT BRASS FSTNR FASTENER BRZ BRONZE FT FOOT BSHG BUSHING FIXED CAB CABINET GSKT GASKET CAP CAPACITOR MOL HANDLE CER CERAMIC HEX HEXAGON CHAS CHASSIS HEX HEXAGONAL HEAD
10. F lB 05355 le ej k 05360 5 8334 10K 7 05325 R370 D zm 200 H 4 5 La eto k 5 NECH 0385 05365 RTS od ick BEIM 2 20 n ak iv A377 9 9375 Dif oo i r 200 gt 9 380 T JA LLL LLL PARTIAL MAIN BOARD 22 PARTIAL A2 DISPLAY BOARD paso pasa di DM502 gev B nov 1974 INTEGRATOR A D CONVERTER DISPLAY lt gt 48 PARTIAL Al MAIN BOARD TC I5VOLTS Sv an 335 2 Tarur gt 15 5 7 T 2VOLTS Gare i 1 i fonte IS H 2vOLTS i 1 1 4 I CR430 jon gt 9VOLTS UNREGULATED i n 300uF la SEE PARTS LIST FOR EARLIER VALUES SERIAL NUMBER RANGES OF PARTS MARKED ed WITH BLUE OUTLINE 45VOLTS I case TC444 le suo RANGE FUNCTION 12345 1890112138 2223 24 25 2 27 2520303 3233435 wawapo saas COW O O OMO O e je D 0 O e eje D DO 0 ele O O je O DO e ele e e ele e e eje ele je DOBSOBO O ele
11. 00 56289 LP66A1A104K004 C263 290 0536 00 PXD ELCTLT 10UF 208 25V 90201 TDC1O6MO25NLF C265 283 0065 00 CAP FXD CER DI 0 001UP S 100v 72982 805 505 1022 27 290 0525 00 CAP FXD ELCTLT 4 7UF 208 50V 56289 1960475 0050 1 285 283 0001 00 FXD CER DI 0 005UF 100 08 500V 72982 831 559 502 287 283 0065 00 CAP FXD CER DI 0 001UF 5 100V 72982 805 505 1022 C291 285 1101 00 FXD PLS1C 0 022 UF 108 200V 19396 PT485 022 200 10 C300 285 1101 00 CAP FXD PLSTC 0 022 10 2007 19396 PT485 022 200 10 C310 290 0536 00 CAP FXD ELCTLT 10UF 208 25V 90201 TDClO6MO2SNLF C312 290 0525 00 CAP FXD ELCTLT 4 TUF 209 50V 56289 196D475X0050KAl C315 281 0205 00 CAP VAR PLSTC 5 5 65PF 100 80031 CO10GA 60E C316 285 1102 00 FXD PLSTC 0 1UF 208 100VDC REEL 19396 PT720B104m C320 290 0536 00 FXD ELCTLT 10UF 208 25V 90201 TDClO6MO25NLF 6325 290 0512 00 CAP FXD ELCTLT 22UF 208 15V 56289 1960226 0015 1 C330 283 0626 00 FXD MICA D 1800PF 5 500V 00853 0195 18220 remove for Option 2 REV 1975 3 3 FEB Electrical Parts List DM 502 Tektronix Serial Model No Mfr Ckt No Part No Eff Dscont Name amp Description Code Mfr Part Number 4001 290 0525 00 CAP FXD ELCTLT 4 7UF 208 50V 56289 1960475 0050 1 C405 290 0525 00 CAP FXD ELCTLT 4 7UF 208 50V 56289 1960475 0050 C410 290 0725 00 CAP FXD ELCTLT 100UF 75 108 S
12. 01121 CB1525 R360 315 0152 00 RES PXD CMPSN 1 5K 54 0 258 01121 1525 R364 315 0152 00 RES FXD CMPSN 1 5K 5 0 25 01121 1525 R365 315 0152 00 RES FXD CMPSN 1 5K OHM 51 0 25W 01121 1525 lRemove for Option 2 36 REV C FEB 1975 Electrical Parts List DM 502 Tektronix Serial Model No Mfr Ckt Port No Name amp Description Code Mfr Part Number R369 315 0472 00 RES FXD CMPSN 4 7K OHM 5 0 25W 01121 4725 R370 315 0201 00 RES FXD CMPSN 200 OHM 5 0 25W 01121 2015 R372 315 0201 00 RES FXD CMPSN 200 OHM 5 0 25W 01121 2015 R374 315 0103 00 RES FXD CMPSN 10K OBM 5 0 25W 01121 1035 R375 315 0103 00 RES FXD CMPSN 10K OHM 5 0 25W 01121 1035 R377 315 0201 00 RES FXD CMPSN 200 OHM 5 0 25W 01121 2015 R380 315 0103 00 RES FXD CMPSN 10K OHM 5 0 25W 01121 1035 R382 315 0201 00 RES FXD CMPSN 200 OKM 5 0 25W 01121 CB2015 R383 315 0201 00 RES FXD CMPSN 200 OHM 5 0 25W 01121 2015 R400 301 0681 00 RES FXD CMPSN 680 OHM 5 0 50W 01121 EB6815 R405 301 0681 00 RES FXD CMPSN 680 OHM 5 0 50W 01121 6815 R415 321 0371 00 RES PXD FIIM 71 5K OHM 1 0 125W 75042 CEATO 7152F R418 304 0681 00 RES PXD CMPSN 680 OHM 108 1W 01121 GB6811 R422 321 0335 00 RES FXD FILM 30 1K OHM 18 0 125W 75042 CEATO 3012F R427 303 0511 00 RES FXD CMPSN 510 ORM 5 1W 01121 5115 R437 304 0181 00 RES FXD CMPSN 180 OHM 10 1W 01121 GB1811 R440 307 0106 00 RES FXD CMPSN 4 7 OHM 5
13. 0375 151 0341 00 TRANSISTOR SILICON NPN 07263 23565 Q380 151 0281 00 TRANSISTOR SILICON NPN 03508 16 4039 0440 151 0134 00 TRANSISTOR SILICON PNP 04713 2N2905A 0450 151 0341 00 TRANSISTOR SILICON NPN 07263 283565 Remove for Option 2 74 REV C FEB 1975 Electrical Parts List DM 502 Tektronix Serial Model Mfr Ckt No Part No Dscont Name amp Description Code Mfr Part Number R95 315 0102 00 RES FXD CMPSN 1K 5 0 250 01121 CB1025 R100 315 0101 03 RES PXD CMPSN 100 OHM 5 0 25W 01121 1015 R105 321 0895 07 RES FXD FILM 90 0 14 0 1258 91637 MFF1816C90R00B R106 308 0772 00 RES FXD WW 9 0 1 38 73138 91A20R00M R107 308 0770 00 RES FXD WW 1 0 1 3 AXIAL LD 91637 RLS286 BlROO0B R110 308 0769 00 RES FXD WW 0 1 OHM 0 1 3W 4 TERM 91637 RLS2B6 BR1000B R120 321 0184 00 RES FXD FILM 806 OHM 75042 CEATO 8060F R124 321 0365 00 RES FXD PILM 61 9K 14 0 1258 75042 CEATO 6192F R128 321 0285 00 RES FXD FILM 9 09K OHM 1 0 125W 75042 CEATO 9091F R130 311 1749 00 RES VAR NONWIR TRMR 1 5K OHM 0 75W 73138 91AR1500M R135 307 0465 00 03888 FL1 2 105F R136 321 1485 00 75042 CEATO 1114F R140 321 0481 04 RES FXD FILM 1M 0HM 0 18 0 125W 91637 MFF1816D100038 R142 308 0541 00 RES FXD WW lK OHM 0 1 3W AXIAL LD 91637 RS2B B10000B R145 R146 325 0186 00 RES SET MTCH 9 9M OHM 90K 10 OHM 80009 325 0186 00 R147 8155 311 1564 00 RES VAR NONWIR 500 OHM 20 0 50
14. 07029 INDIANAPOLIS IN 46206 COLUMBUS NB 68601 REV B JAN 1975 Electrical Parts List DM 502 Tektronix Serial Model Mfr Ckt No Part No Eff Dscont Name amp Description Code Mfr Part Number Al 670 3495 00 8010100 5019999 BOARD ASSY MAIN 80009 670 3495 00 670 3495 01 020000 BOARD ASSY MAIN 80009 670 3495 01 Al 670 3694 00 010100 8019999 BOARD ASSY MAIN OPTION 2 80009 670 3694 00 Al 670 3694 01 8020000 CKT BOARD ASSY MAIN OPTION 2 80009 670 3694 01 A2 670 3509 00 CKT BOARD ASSY DISPLAY 80009 670 3509 00 285 1106 00 CAP FXD PLSTC 0 22UF 20 600V 14752 23081F223 C110 283 0279 00 xB020000 CAP PXD CER DI 0 001UF 208 30007 72982 878Y55102M C120 290 0536 00 CAP FXD ELCILT 10UF 20V 25V 90201 TDClO6MO2SNLF C130 283 0003 00 CAP FXD CER DI 0 01UF 80 208 150V 72982 855 547 1032 Cl42 283 0626 00 CAP FXD MICA D 1800PF 5 500V 00853 D195E18270 283 0626 00 CAP FXD MICA D 1800PF 58 500v 00853 D195518270 C150 281 0182 00 CAP VAR PLSTC 1 8 10PF 300V 34553 2222 809 05002 C151 281 0515 00 CAP FXD CER DI 27PF 1 35PF 500V 72982 302 000 0502702 C152 281 0564 00 CAP PXD CER DI 24PP 5 500V 72982 301 000 0602402 C154 281 0579 00 CAP FXD CER DI 21PF 58 500V 72982 301 050c0G02103 C155 281 0184 00 CAP VAR PLSTC 2 18PF S00VDC 34553 2222 809 05003 C157 285 0596 00 CAP FXD PLSTC 0 01UF 18 100v 56289 490 10311 158 285 0719 00 CAP FXD PLSTC 0 015UF 58 10
15. 115 V filtered DC filtered DC 25 VAC 125 VAC winding winding filtered DC Collector Emitter msoo 7 lead of NPN barrier Series Pass plug in These outputs must be buffered before using them to drive external inputs See buffering circuit Used in the DM 502 Only the Temp Out Temp Gnd and HI and LO inputs are factory wired The others must be installed by the user See accompanying illustration for jumper locations for connections BCD outputs are serialized by digits in an 8 4 2 1 code This code is not valid when the MSD line is high When the MSD and the one are high the fourth significant digit is a one A two may also be encoded as well as overrange information db Converter Converts de output voltage from the ac converter to a logarithmic output voltage BLOCK DIAGRAM Ac Converter Rectifies ac voltages in HI the ac modes for applica tion to the integrator or Attenuator and Input analog to digital con Switching verter Comprises input switching attenuation and protection for the various measurement Ac Voltage Digital Processor BCD to Seven Segment modes and Current Analog to Digital Converter Combines counting storage t Integrates a de voltage propor data multiplexing and random Converte he binary ti to tl be De Voltage ional to the me
16. 125 ID 1 5 OD 0 75H 80009 366 1606 00 213 0153 00 2 SETSCREW 5 40 X 0 125 INCH HEX SOC STL 74445 OBD 348 0031 00 010750 1 GROMMET PLASTIC 0 156 INCH DIA 80009 348 0031 00 4 366 1402 27 1 PUSHBUTTON INT 80009 366 1402 27 366 1557 19 1 PUSHBUTTON DB 80009 366 1557 19 5 366 1422 01 1 KNOB LATCH 80009 366 1422 01 ATTACHING PARTS 6 214 1840 00 1 PIN KNOB SECRG 80009 214 1840 00 IR 7 129 0064 02 1 POST BDG ELEC WHITE 5 WAY MINIATURE 58474 DF21WTC ATTACHING PARTS 8 210 0457 00 1 NUT PLAIN EXT W 6 32 X 0 312 INCH STL 83385 OBD 9 210 0202 00 1 TERMINAL LUG SE 6 78189 2104 06 00 2520N Num 10 129 0064 00 1 POST BDG ELEC CHARCOAL 5 WAY MINIATURE 58474 BB10167G13T ATTACHING PARTS 11 210 0457 00 1 NUT PLAIN EXT W 6 32 X 0 312 INCH STL 83385 OBD 12 358 0181 00 1 INSULATOR BSHG CHARCOAL 58474 BBlOl66Gl3BX ie 13 129 0064 01 1 POST BDG ELEC RED 5 WAY MINIATURE 58474 BB10167G2BX ATTACHING PARTS 14 210 0457 00 1 NUT PLAIN EXT W 6 32 X 0 312 INCH STL 83385 OBD 15 358 0181 01 1 INSULATOR BSHG RED 58474 BB1066G2 16 131 1652 00 1 CON RCPT ELEC l 1 MALE CONTACT 0000A RA0302 ATTACHING PARTS 210 0255 00 1 TERMINAL LUG 0 391 ID INT TOOTH 80009 210 0255 00 w Saga 17 426 0681 00 2 FR PUSH BUTTON GRAY PLASTIC 80009 426 0681 00 18 333 1976 00 1 PANEL FRONT 80009 333 1976 00 333 1976 01 1 PANEL FRONT OPTION 2 80009 333 1976 01 ATTACHING PARTS 19
17. 152 0585 00 SEMICOND DEVICE SILICON BRIDGE 75V 75MA 15281 WO2M CR430 152 0585 00 SEMICOND DEVICE SILICON BRIDGE 75V 75MA 15281 W02M 435 152 0107 00 SEMICOND DEVICE SILICON 3757 4OOMA 80009 152 0107 00 DS350 150 1022 00 LAMP LED RED 50522 MAN72 05355 150 1022 00 LAMP LED RED 50522 72 05360 150 1022 00 LAMP LED RED 50522 72 05365 150 1021 00 LAMP LED RED 50522 73 F100 159 0126 00 FUSE CARTRIDGE 2 5A 250 VAC FAST BLOW 71400 AGC2 1 2 2100 129 0064 01 POST BDG ELEC RED 5 WAY MINIATURE 58474 BB10167G2BX 3110 129 0064 00 POST BDG ELEC CHARCOAL S WAY MINIATURE 58474 BINP BBl0167G13T 3115 129 0064 02 POST BDG ELEC WHITE 5 WAY MINIATURE 58474 DF21WTC 22501 131 1652 00 CONN RCPT ELEC 1 1 MALE CONTACT 0000A RA0302 9165 151 1005 00 TRANSISTOR SILICON JFE N CHANNEL 15818 01490 9170 151 0188 00 TRANSISTOR SILICON PNP 04713 283906 02301 151 0341 00 TRANSISTOR SILICON NPN 07263 283565 02351 151 0341 00 TRANSISTOR SILICON NPN 07263 283565 02451 151 1005 00 TRANSISTOR SILICON JFE N CHANNEL 15818 01490 02551 151 1005 00 TRANSISTOR SILICON JFE N CHANNEL 15818 01490 02601 151 1005 00 TRANSISTOR SILICON JFE N CHANNEL 15818 01490 9350 151 0301 00 TRANSISTOR SILICON PNP 04713 2N2907A Q355 151 0301 00 TRANSISTOR SILICON PNP 04713 2N2907A 9360 151 0301 00 TRANSISTOR SILICON PNP 04713 2N2907A 9365 151 0301 00 TRANSISTOR SILICON PNP 04713 2N2907A 9370 151 0302 00 TRANSISTOR SILICON NPN 04713 2N2222A
18. 530153 1 71 214 0579 00 2 TERM TEST 0 40 INCH LONG 80009 214 0579 00 72 131 0566 00 1 LINK TERM CONNE 0 086 DIA X 2 375 INCH L 0000C 1 2007 1 214 1291 00 1 HEAT SINK ELEC XSTR 0 72 OD X 0 375 H 05820 207 AB 131 0993 02 LINK TERM CONNE 2 WIRE RED 00779 1 530153 0 131 0993 09 1 LINK TERM CONNE 2 WIRE WHITE 00779 530153 1 73 426 0724 04 1 FR SECT PLUG IN BOTTOM 80009 426 0724 04 74 214 1061 00 1 SPRING GROUND FLAT 80009 214 1061 00 75 426 0725 05 1 FR SECT PLUG IN TOP 80009 426 0725 05 76 352 0169 00 1 CONN BODY PL EL 2 WIRE BLACK 80009 352 0169 00 77 352 0161 01 1 CONN BODY PL EL 3 WIRE BROWN 80009 352 0161 01 78 352 0165 02 2 HOLDER TERM CON 7 WIRE RED 80009 352 0165 02 79 352 0168 09 2 HOLDER TERM CON 10 WIRE WHITE 80009 352 0168 09 80 131 0707 00 39 CONTACT ELEC 0 48 L 22 26 AWG WIRE 22526 47439 81 175 0830 00 WIRE ELECTRICAL 7 WIRE RIBBON 08261 TEK 175 0830 00 82 175 0833 00 WIRE ELECTRICAL 10 WIRE RIBBON 23499 175 0833 00 54 REV B JAN 1975 Mechanical Parts List DM 502 Fig amp Index Tektronix Serial Model No Mfr No Port No Dscont 12345 Name amp Description Code Mfr Part Number 175 0825 00 FT WIRE ELECTRICAL 2 WIRE RIBBON 23499 175 0825 00 175 0826 00 FT WIRE ELECTRICAL 3 WIRE RIBBON 08261 175 0826 00 ACCESSORIES 070 1726 00 1 MANUAL TECH INSTRUCTION NOT SHOWN 80009 070 1726 00 010 6430 00 1 PROBE TEMPERATURE NOT SHOWN 80009 010
19. 83 R215 HS R372 G2 C198 G5 P212 H5 R217 G5 8374 F2 C199 G4 P340 42 R218 G5 R375 G2 C208 H5 P342 48 220 H6 8377 G2 C220 G6 P350 12 R224 H6 R380 H1 230 5 P352 R225 H6 R382 H2 C235 L5 R230 5 R383 H2 C251 R232 R400 M6 C257 14 0165 4 R235 5 8405 260 Q170 ES 237 15 9415 5 C263 t4 Q230 15 240 8418 15 C265 0235 15 R243 14 422 J6 C270 0245 15 R245 L4 8427 15 C285 Q255 14 R247 8437 J3 C287 14 0260 14 R250 440 J4 C291 B2 Q350 12 R251 R450 J3 C300 A2 Q355 12 R255 M3 R452 J4 C310 A3 Q360 12 R257 L3 453 J4 C312 B2 0365 H2 8260 M4 C315 ci Q370 G2 R265 L4 C316 B2 Q375 G2 R267 12 C320 B1 Q380 H2 R268 12 C325 F2 0440 1 8269 12 RT100 DS C330 DI 0450 J3 8270 12 RT220 G6 C400 12 R271 12 405 R100 05 8275 12 C410 K5 R105 C4 R277 12 5100 B6 C412 K5 R106 5 8279 5110 D3 C420 15 R107 C5 R280 K2 5200 C425 5 R110 C5 R282 K2 C437 K4 R120 H6 9285 12 C440 J3 R124 H6 R290 7410 4 C442 F2 R128 05 R291 D2 C444 H1 R130 D6 R293 B2 R135 ES R295 C2 0120 G6 CR100 05 R136 E5 R297 0135 ES CR110 C6 R140 C5 R300 C2 U195 5 CR136 05 R142 C5 R302 2 0210 G5 CR165 ES R145 R304 B2 0220 G5 CR166 E5 R146 B4 8305 C2 0250 CR187 F6 R147 R310 0290 2 CR195 6 R155 B5 R315 B1 0325 2 CR230 16 R157 B5 8325 02 0335 E1 CR235 L6 R165 E4 R328 F2 0340 G1 CR237 L4 R168
20. dBV mode As pin 3 of U220 goes positive the output goes positive The base of Q120B goes positive and the collector negative providing negative feedback The collector current of Q120A always equals the current through R212 at 0 dB The necessary voltage at the output of U220 is logarithmic due to the logarithmic characteristics of Q120B in the feedback loop As the temperature increases the gain of Q120B decreases This is compensated for by RT220 decreasing in value with increasing temperature Ohms Converter U135 is an operational amplifier The current setting resistances are connected from the output to the plus input terminal of U135 The unknown resistances are connected from the plus terminal to floating ground See Fig 2 1 Negative feedback occurs from the output of U135 to the negative input terminal R130 is the calibration adjustment R135 and R136 are switched in and out of the negative feedback loop to provide bias current compensa tion The value of the current setting resistance is always equal to one half of the full scale measurement value except on the 200 range as shown on the range HI Lo function switch The 200 scale uses 1 and the gain of the analog to digital converter is increased by a factor of ten R130 adjusts the gain of the amplifier to produce one volt across the current setting resistance 0 1 V in the 200 range As long as the unknown resistance is within the measurement range
21. the circuitry adjusts the current so that the drop across the current setting resistance is one volt This current flows through the unknown resistance varying the voltage at the plus terminal of U135 This voltage is then fed to the analog to digital converter input Temperature Measurement Circuitry This circuitry operates on the principle that a change in base to emitter voltage of a bipolar transistor is propor tional to the temperature of the junction as the collector current is changed between two levels A square wave about 2 kHz is generated by Q230 and 0235 operating as an astable multivibrator The square wave is applied to the gates of Q255 and Q260 The collector to base voltage of the temperature sensing transistor in the probe is held constant When fet 0255 is off the current to the probe through R255 and R257 is approximately one tenth the on current To A to D converter Current setting resistance Fig 2 1 Simplified diagram of Ohms Converter 22 REV A OCT 1974 When 0230 is off and 0235 is on Q255 is off and the voltage at pin 2 of U250A goes negative The output of U250A goes positive reducing the temperature variable base emitter current of the sensing transistor until 2 of U250A is at ground A positive going square wave results at the output of U250A with an amplitude proportional to the temperature of the base emitter junction Q260 is on and Q245 is off due to the action of Q230
22. 0 25W 01121 4765 R450 315 0621 00 RES FXD CMPSN 620 OHM 5 0 25W 01121 6215 R452 315 0622 00 RES FXD CMPSN 6 2K OHM 5 0 25W 01121 6225 R453 315 0562 00 RES FXD CMPSN 5 6K OHM 5 0 25W 01121 5625 RTlO0 150 0131 00 LAMP INCAND 0 025A 1207 71744 12095 RT220 307 0472 00 RES THERMAL 100K 5 NTC DISC 15454 10E104 JS 5100 260 1208 00 SWITCH PUSH DPDT 71590 2 010000 359 5110 263 1106 00 ACTR ASSY CAM SW TIME C M 80009 263 1106 00 5200 260 1332 00 SWITCH PUSH 80009 260 1332 00 7410 120 0958 00 XFMR PHR SDN 80009 120 0958 00 0120 156 0197 00 MICROCIRCUIT LI 5 TRANSISTOR ARRAY 86684 CA3086 0135 156 0512 00 MICROCIRCUIT LI OPERATION AMPLIFIER 27014 1M308N 0195 156 0511 00 MICROCIRCUIT LI OPERATIONAL AMPLIFIER 18324 NES31V 0210 156 0067 00 MICROCIRCUIT LI OPERATIONAL AMPLIFIER 80009 156 0067 00 9220 156 0512 00 MICROCIRCUIT LI OPERATION AMPLIFIER 27014 0250 156 0158 00 MICROCIRCUIT LI DUAL OPERATIONAL AMPLIFIER 18324 S5558V 0290 156 0477 00 MICROCIRCUIT LI ANAL A D SYS MOS 17856 12111 0325 156 0402 00 MICROCIRCUIT DI TIMER 18324 NESSSV 0335 156 0476 00 MICROCIRCUIT LI DIGTL SECT OF A D SYS MOS 17856 10110 0340 156 0128 00 MICROCIRCUIT DI SGL BCD TO 7 SEG DCDR DRVR 01295 SN7447AN 0345 156 0093 00 MICROCIRCUIT DI HEX INVERTER 01295 SN7416N 0420 156 0496 00 MICROCIRCUIT LI VOLT REG DUAL TRACKING 49956 RC4194D VR120 152 0317 00 SEMICOND DEVICE ZENER 0 25W 6 2V 5 81483 143497 VR270 152 0317 00 SEMICON
23. 0V 56289 410 113 Cl 8 283 0003 00 FXD CER DI 0 01UF 80 208 150V 72982 855 547 1032 C170 283 0003 00 CAP FXD CER DI 0 01UF 80 208 150V 72982 855 547 1032 C175 290 0535 00 FXD ELCTLT 33UF 208 10V 56289 1960336 0010 C190 290 0527 00 CAP PXD ELCTLT 15UF 20 207 90201 TDC156M020NLP C192 281 0661 00 CAP FXD CER DI 0 8PF 0 1PF 500V 72982 301 000C0G08088 C195 290 0723 00 CAP FXD ELCTLT lSOUF 20 6VDC DIPPED TANT 56289 1960157 0006 C197 290 0525 00 8010100 8019999 CAP FXD ELCTLT 4 7UF 208 50V 56289 1960475 0050 1 C197 290 0536 00 8020000 CAP FXD ELCTLT 10UF 20 25V 90201 TDC106MO2SNLF C198 290 0536 00 8010100 8019999 CAP FXD ELCTLT 10UF 20 25V 90201 TDCl06MO2SNLF C198 290 0527 00 020000 CAP FXD ELCTLT 15UF 20v 20V 90201 TDCl56MO20NLF C199 290 0512 00 8010100 5019999 CAP FXD ELCTLT 22UF 20 15V 56289 1960226 0015 1 C199 290 0535 00 020000 FXD ELCTLT 33UF 20 10V 56289 196D336X0010KAl C208 281 0513 00 CAP FXD CER DI 27PF 5 4PF 500V 72982 301 000P260270M C220 283 0065 00 DI 0 001UF 5 100V 72982 805 505 1022 C230 283 0065 00 DI 0 001UF 54 72982 805 505 1022 C235 283 0065 00 1 0 0010 54 100 72982 805 505 1022 C251 281 0546 00 D1 330PF 10 500V 72982 301 000X5P0331K C253 283 0114 00 72982 805 509B1527 254 283 0114 00 72982 805 50981521 257 283 0065 00 72982 805 505 1022 C260 285 0808
24. 210 0405 00 2 NUT PLAIN HEX 2 56 X 0 188 INCH BRS 73743 2 12157 402 20 210 0259 00 1l TERMINAL LUG 0 099 ID INT TOOTH SE 80009 210 0259 00 21 210 0001 00 1 WASHER LOCK INTL 0 092 ID X 0 18 0D STL 78189 1202 00 00 0541c 22 211 0034 00 2 SCREW MACHINE 2 56 X 0 500 INCH PNH STL 77250 23 331 0314 00 1 WINDOUT READOUT 80009 331 0314 00 24 426 0916 00 1 FRAME RDOUT WDO 80009 426 0916 00 25 386 3149 00 1 SUBPANEL FRONT PLASTIC 80009 386 3149 00 ATTACHING PARTS 26 213 0227 00 2 SCR TPG THD FOR 6 32 X 0 50 100 DEG FLH ST 27 213 0229 00 2 SCR TPG THD FOR 6 20 X0 375 100 DEG FLH STL 83385 OBD Se Wa Se 28 214 1513 01 1 LCH PLUG IN RET 80009 214 1513 01 ATTACHING PARTS 29 213 0254 00 1 SCR TPG THD CTG 2 56X0 25 100 DEG FLH STL 45722 mim NUS GE 30 337 2130 00 1 SHIELD ELEC SUBPL REAR 80009 337 2130 00 31 1 BOARD ASSY DISPLAY SEE 2 EPL 32 131 0608 00 17 CONTACT ELEC 0 365 INCH LONG 22526 47357 33 384 1129 00 1 EXTENSION SHAFT 5 607 INCH LONG 80009 384 1129 00 672 0478 00 1 BOARD ASSY W CAM SW 80009 672 0478 00 672 0479 00 1 BOARD ASSY W CAM SW 80009 672 0479 00 ATTACHING PARTS 34 213 0146 00 4 SCR TPG THD FOR 6 20 X 0 313 INCH PNH STL 83385 S al s ap 263 1106 00 1 ACTR ASSY CAM S W TIME CM 80009 263 1106 00 ATTACHING PARTS 35 211 0116 00 8 SCR ASSEM WSHR 4 40 X 0 312 INCH PNH BRS 83385 OBD REV B JAN 1975 53 Mechanical Parts List DM 502
25. 6430 00 003 0120 00 1 TEST LEADS PAIR NOT SHOWN 80009 003 0120 00 REPACKAGING 065 0151 00 1 CARTON ASSEMBLY NOT SHOWN 80009 065 0151 00 REV JAN 1975 5 5 MANUAL CHANGE INFORMATION At Tektronix we continually strive to keep up with latest electronic developments by adding circuit and component improvements to our instruments as soon as they are devel oped and tested Sometimes due to printing and shipping requirements we can t get these changes immediately into printed manuals Hence your manual may contain new change information on following pages A single change may affect several sections Sections of the manual are often printed ot different times so some of the information on the change pages may already be in your manual Since the change information sheets are carried in the manval until ALL changes are permanently entered some duplication may occur If no such change pages appear in this section your manual is correct as printed MANUAL CHANGE INFORMATION PRODUCT DM 502 CHANGE REFERENCE __ 4 175 __ 070 1726 00 DATE 1 27 75 DESCRIPTION Changes are circled below REAR INTERFACE CONNECTOR ASSIGNMENTS Floating Common Use as common for gli data outputs mV Use 210 load ele Te plug in These outputs must be buttered belore using them to drive external inputs See text for sultabie buf
26. 9 32 9 39 3 3 97a 37a 9 Vor 9 40 W W 4 V ing counten CON TENTE o Fig 2 4 Measurement interval timing Reprinted by permission of Siliconix Inc Display The bcd data from the data buffers is applied to 0340 a bcd to seven segment decoder All segments of digits one two and three are connected in parallel to U340 The high outputs from the digit buffers are inverted by U345A and D which drive Q350 for digit one Q355 for digit two Q360 for digit three and Q365 for the most significant digit When the collectors of these transistors are high the particular digit is displayed This is accomplished in a one three two four sequence The common terminal for the polarity signs is also activated by Q365 at the most significant digit time 5110 37 38 and S200 disconnect the polarity signs when not appropriate for the measurement mode in use S200 is on the dB switch When pin 5 of U335 is high the positive sign is lighted When pin 5 of U335 is low the negative sign is illuminated by the action of Q375 and U345F The decimal positions are changed by contacts in the range function and dB switches through Q370 As pin 16 of U335 is the bcd one line to the seven segment decoder when the most significant digit is present pin 16 is high This is converted to a low and connected to the cathodes of the ones segments in the most significant digit module The contents of the static latches are mult
27. D DEVICE ZENER 0 25W 6 2V 5 81483 143497 VR300 152 0306 01 SEMICOND DEVICE ZENER 0 4W 9 1V 5 04713 1N960B vR310 152 0317 00 SEMICOND DEVICE ZENER 0 25W 6 2V 5 81483 1N3497 VRAO0 152 0243 00 SEMICOND DEVICE ZENER O 4W 15V 5 81483 1N965B VR40S 152 0243 00 SEMICOND DEVICE ZENER 0 4W 15V 5 81483 1N965B lremove for Option 2 REV C FEB 1975 3 7 Section 3 DM 502 SERVICE INFORMATION SYMBOLS AND REFERENCE DESIGNATORS Electrical components shown on the diagrams are in the following units unless noted otherwise Capacitors Values one or greater are in picofarads pF Values less than one are in microfarads uF Resistors Ohms Q Symbols used on the diagrams are based on ANSI Y32 2 1970 Logic symbology is based on MIL STD 806B in terms of positive logic Logic symbols depict the logic function performed and may differ from the manufacturer s data The following special symbols are used on the diagrams External Screwdriver adjustment External control or connector Clockwise control rotation in direction of arrow lt gt Refer to diagram number indicated in diamond 7 Refer to waveform number indicated in hexagon e Connection soldered to circuit board Connection made to circuit board with interconnecting pin V Blue tint encloses components located on circuit board P O circuit board 3 1 Service Available Tektronix Inc provides complete instrument repair and a
28. Gain and Compensation Set the range function switch to the 500 AC VOLTS position Connectan accurately known ac voltagenear 500 V ac rms at 100 Hz to the HI and LO binding posts Adjust R155 500 V Ac Gain for a display reading of the applied voltage one count Now change the frequency of the applied voltage to 10 kHz and adjust C155 500 V Ac Comp fora display reading of the applied voltage one count These adjustments interact Redo both as required for accurate calibration 15 Adjust dB Zero and 20 dB Make certain the jumper is in the dBm position Set the range function switch to the 2 AC VOLTS position and push the dB pushbutton Apply 0 07746V ac rms at 1 kHz to the HI and LO binding posts Adjust R205 dB Zero for a display reading of all zeros three counts Now apply 0 00869 V ac rms at 1 kHz and adjust R215 20 dB for a display reading of 19 00 three counts Apply 0 69036 V ac rms at 1 kHz and check for a display reading of 19 00 within specification limits by at least ten counts Now switch the jumper to the dBV position apply 1 0000 V ac rmsat 1 kHz and check for a display reading of all zeros within specification limits by at least ten counts 16 Check All AC mA Ranges Apply an accurately known ac current at a frequency of 1 kHz with an amplitude of approximately 596 below full scale values as shown on the range function switch to the HI and LO binding posts Check each AC mA position for accuracy withi
29. M 1 0 125W 75042 CEATO 1620F R2501 315 0103 00 RES PXD CMPSN 10K OHM 51 0 25W 01121 1035 82511 321 0222 00 RES PXD FILM 2K 14 0 1258 75042 CEATO 2001F R255 321 0365 02 RES FXD FILM 61 9K OHM 0 5 0 125W 91637 18160619010 R257 322 0643 01 RES FXD FILM 600K OHM 0 58 0 25W 75042 CEBTO 6003D R260 315 0104 00 RES FXD CMPSN 100K OHM 5 0 25W 01121 1045 R265 315 0683 00 RES FXD CMPSN 68K OHM 5 0 25W 01121 CB6835 R267 321 0106 00 RES FXD FILM 124 1 0 1258 75042 0 1240 82681 311 1731 00 RES VAR NONWIR TRMR 20 OHM O 5W 73138 91A20RO0M R269 321 0182 00 RES FXD PILM 768 OHM 1 0 125W 75042 0 7680 R270 311 1222 00 RES VAR NONWIR 100 20 0 50 80294 3386 04 500 R271 321 0176 00 RES FXD PILM 665 1 0 125 75042 CEATO 6650F R275 321 0446 00 RES FXD FILM 432K OHM 18 0 125W 75042 CEATO 4323F 827711 321 0397 00 RES FXD FILM 133K OHM 18 0 125W 75042 CEATO 1333F m279l 321 0219 00 RES FXD FILM 1 87K OHM 1 0 125W 75042 CEATO 1871F R280 311 1564 00 RES VAR NONWIR 500 OHM 208 0 50W 73138 91A 500ROM R282 321 0423 00 RES FXD FILM 249K OHM 18 0 125W 75042 2493 82851 321 0380 00 RES FXD FILM 88 7K ORM 18 0 125W 75042 8872 R290 303 0105 00 RES FXD CMPSN 1M OHM 5 1W 01121 1055 R291 315 0104 00 RES FXD CMPSN 100K 5 0 250 01121 1045 R293 321 0978 01 RES FXD FILM 11 02K OHM 0 5 0 125W 91637 MFF1816G11021D 8295 311 1565 00 RES VAR NO
30. MICONDUCTOR GROUP WAKEFIELD ENGINEERING INC SPECTRA STRIP CORP BERG ELECTRONICS INC GAVITT WIRE AND CABLE DIVISION OF RSC INDUSTRIES INC USM CORP PARKER KALON FASTENER DIV SUPERIOR ELECTRIC CO THE CENTRALAB ELECTRONICS DIV OF GLOBE UNION INC FISCHER SPECIAL MFG CO HOLO KROME PHEOLL MANUFACTURING CO DIVISION INDUSTRIAL RETAINING RING CO ADDRESS 2015 2ND ST P O BOX 3608 P O BOX 5012 AUDUBON ROAD 7100 LAMPSON AVE YOUK EXPRESSWAY 455 N QUINCE ST 1 PEEKAY DRIVE 383 MIDDLE ST 5757 N GREEN BAY AVE 446 MORGAN ST 31 BROOK ST WEST 5700 W ROOSEVELT RD ST CHARLES ROAD P O BOX 500 34 FOREST ST 2530 CRESCENT DR 57 CORDIER ST CITY STATE ZIP BERKLEY CA 94710 SPRINGMILL PA 16875 HARRISBURG PA 17105 DALLAS TX 75222 WAKEFIELD MA 01880 GARDEN GROVE CA 92642 NEW CUMBERLAND PA 17070 ESCONDIDO CA 92025 CLIFTON NJ 07014 BRISTOL CT 06010 MILWAUKEE WI 53201 CINCINNATI OH 45206 HARTFORD CT 06110 CHICAGO IL 60650 ELGIN IL 60120 BEAVERTON OR 97077 ATTLEBORO MA 02703 BROADVIEW IL 60153 IRVINGTON NJ 07111 Mechanical Parts List DM 502 Fig amp Index Tektronix Serial Model No Mfr Part No Dscont 12345 Name amp Description Code Mfr Part Number 1 337 1399 02 1 SHLD ELECTRICAL SIDE WITH INSULATOR 80009 337 1399 02 2 337 1399 00 1 SHLD ELECTRICAL SIDE 80009 337 1399 00 3 366 1606 00 1 KNOB GRY DSPL O
31. NWIR 250 20 0 50 73138 91A250ROM R297 321 0385 00 RES FXD FILM 100K OHM 18 0 125W 75042 CEATO 1003F R300 315 0184 00 RES FXD CMPSN 180K OHM 5 0 25W 01121 1845 R302 315 0104 00 RES FXD CMPSN 100K OHM 5 0 25W 01121 1045 R304 321 0369 00 RES FXD FILM 68 1K OEM 11 0 125W 75042 CEATO 6812F R305 311 1228 00 RES VAR NONWIR 10K OHM 208 0 SOW 80294 3389F P31 103 R310 321 0184 00 RES FXD FILM 806 OHM 18 0 125W 75042 CEATO 8060F R315 315 0393 00 RES FXD CMPSN 39K OHM 5 0 25W 01121 CB3935 R325 315 0200 00 RES FXD CMPSN 20 5 0 258 01121 2005 R328 311 1559 00 RES VAR NONWIR 10K OHM 20 0 SOW 73138 91A 10001M R329 321 0255 00 RES PXD FILM 4 42K OHM 18 0 125W 75042 CEATO 4421F R330 321 0306 00 RES 75042 CEATO 1502F R334 315 0103 00 RES 01121 1035 R340 301 0201 00 RES FXD CMPSN 200 01121 2015 R341 301 0201 00 RES FXD CMPSN 200 01121 2015 R342 301 0201 00 RES FXD CMPSN 200 01121 2015 R343 301 0201 00 RES 01121 EB2015 R344 301 0201 00 RES 01121 EB2015 R345 301 0201 00 RES FXD CMPSN 200 OHM 5 0 50W 01121 EB2015 R346 301 0201 00 RES FXD CMPSN 200 OHM 5 0 50W 01121 EB2015 R349 315 0152 00 RES FXD CMPSN 1 5K OHM 5 0 25W 01121 1525 R350 315 0152 00 RES CMPSN 1 5K OHM 5 0 25W 01121 1525 R354 315 0152 00 RES FXD CMPSN 1 5K OHM 58 0 25W 01121 1525 R355 315 0152 00 RES FXD CMPSN 1 5K OHM 5 0 25W 01121 1525 R359 315 0152 00 RES FXD CMPSN 1 5K OHM 5 0 25W
32. OVDC AL 90201 101 050 123 412 290 0725 00 CAP FXD ELCTLT 100UF 75 108 S0VDC AL 90201 TT101V050ClJ3P 420 290 0525 00 CAP FXD ELCTLT 4 7UF 208 50V 56289 196D475X0050KAl 425 290 0525 00 CAP FXD ELCTLT 4 7UF 208 50V 56289 196D475X0050KAl 29 283 0279 00 010280 019999 CAP FXD CER DI 0 001UF 20 3000V 72982 878 55102 C437 290 0727 00 CAP FXD ELCTLT 300UFD 75 10 25VDC AL 90201 TT301V025D1J3P C440 290 0573 00 CAP FXD ELCTLT 2 UF 208 SOV 56289 1960275 0050 1 C442 290 0525 00 CAP FXD ELCTLT 4 7UF 208 50V 56289 196D475X0050KAl C444 283 0080 00 CAP FXD CER DI 0 022UF 80 20 25V 56289 19 611 CRl00 152 0107 00 SEMICOND DEVICE SILICON 375V 400MA 80009 152 0107 00 CR110 152 0585 00 SEMICOND DEVICE SILICON BRIDGE 75V 75MA 15281 WO2M 136 152 0246 00 SEMICOND DEVICE SILICON 400PIV 200MA 07910 012676 CRl 5 152 0246 00 SEMICOND DEVICE SILICON 400PIV 200MA 07910 012676 CR166 152 0246 00 SEMICOND DEVICE SILICON 400PIV 200MA 07910 012676 187 152 0322 00 SEMICOND DEVICE SILICON 15V 28480 5082 2672 CR195 152 0322 00 SEMICOND DEVICE SILICON 15V 28480 5082 2672 152 0141 02 SEMICOND DEVICE SILICON 30V 150 07910 1N4152 R235 152 0141 02 SEMICOND DEVICE SILICON 30V 150MA 07910 14152 2371 152 0141 02 SEMICOND DEVICE SILICON 30V 150MA 07910 184152 CR2401 152 0141 02 SEMICOND DEVICE SILICON 30V 1SOMA 07910 1N4152 CR334 152 0141 02 SEMICOND DEVICE SILICON 30V 150MA 07910 1N4152 CR4lO
33. RECTIFIER CORP RCA CORP ELECTRONIC COMPONENTS MALLORY CAPACITOR CO DIV OF P R MALLORY CO INC DALE ELECTRONICS INC ADDRESS 0 BOX 128 1201 2ND ST SOUTH 0 BOX 5012 ELECTRONICS PARK 60 5 JEFFERSON RD 5005 E MCDOWELL RD 464 ELLIS ST 12515 CHADRON AVE 1710 S DEL MAR AVE 2905 BLUE STAR ST 1300 TERRA BELLA AVE 2201 LAURELWOOD RD 811 E ARQUES 1321 LESLIE AVE 2900 SAN YSIDRO WAY 1501 PAGE MILL RD 35 HOFFMAN AVE 141 SPRING ST 10131 BUBB RD 383 MIDDLE ST 2536 W UNIVERSITY ST 5757 N GREEN BAY AVE 4433 RAVENSWOOD AVE 644 W 12TH ST 2500 HARBOR BlVD 401 N BROAD ST P O BOX 500 22 COLUMBIA RD 6135 MAGNOLIA AVE 9220 SUNSET BlVD 415 S STH ST 3029 E WASHINGTON ST P O BOX 609 CITY STATE ZIP PICKENS SC 29671 MILWAUKEE WI 53204 DALLAS TX 75222 SYRACUSE NY 13201 WHIPPANY NJ 07981 PHOENIX AZ 85036 MOUNTAIN VIEW CA 94042 HAWTHORNE CA 90250 SAN GABRIEL CA 91776 ANAHEIM CA 92806 MOUNTAIN VIEW CA 94040 SANTA CLARA CA 95054 SUNNYVALE CA 94086 ALEXANDRIA VA 22301 SANTA CLARA CA 95051 PALO ALTO CA 94304 HAPPAUGE NY 11787 LEXINGTON MA 02173 CUPERTINO CA 95014 NORTH ADAMS MA 01247 BRISTOL CT 06010 ST LOUIS MO 63107 MILWAUKEE WI 53201 CHICAGO IL 60640 ERIE PA 16512 FULLERTON CA 92634 PHILADELPHIA PA 19108 BEAVERTON OR 97077 MORRISTOWN NJ 07960 RIVERSIDE CA 92506 LOS ANGELES CA 90069 HARRISON NJ
34. RES VAR NONWIR 200K OHM 20 0 50W 73138 91A 20002M R205 311 1553 00 gt 8010370 RES VAR NONWIR 250K OHM 20 0 50W R208 315 0102 00 RES FXD CMPSN 1K OHM 5 0 25W 01121 1025 R210 315 0914 00 RES FXD CMPSN 910K OHM 5 0 25W 01121 9145 R212 321 0242 00 RES FXD FILM 3 24K OHM 18 0 125W 75042 0 3241 R215 311 1554 00 RES VAR NONWIR 200K OHM 20 0 50W 73138 91A 20002M R217 321 1485 00 RES FXD FILM 1 11M OHM 19 0 125W 75042 1114 R218 321 0179 00 RES FXD FILM 715 OHM 1 0 125W 75042 CEATO 7150F R220 321 0370 00 RES FXD FILM 69 8K OHM 18 0 125W 75042 CEATO 6982F R224 321 0689 00 RES FXD FILM 24 9K 0 5 0 125 75042 24920 R225 321 1657 01 RES FXD FILM 673 7 OHM 0 5 0 125W 91637 MFF1816G673R7D R230 315 0103 00 RES FXD CMPSN 10K OHM 5 0 25W 01121 1035 R232 315 0474 00 CMPSN 470K OHM 5 0 25W 01121 4745 82351 315 0474 00 RES FXD CMPSN 470K OHM 5 0 25W 01121 4745 Remove for Option 2 REV C FEB 1975 Electrical Parts List DM 502 Tektronix Serial Model No Mfr Ckt Dscont Name amp Description Code Mfr Part Number 82371 315 0103 00 RES FXD CMPSN 10K OHM 5 0 25W 01121 1035 82401 315 0104 00 FXD CMPSN 100K ORM 5 0 25W 01121 1045 2431 315 0104 00 RES FXD CMPSN 100K OHM 5 0 25W 01121 1045 R2451 315 0104 00 RES PXD CMPSN 100K OHM 5 0 25W 01121 1045 82471 321 0117 00 RES PXD FILM 162 OH
35. RING FLAT GREEN COLORED 80009 214 1139 02 52 214 1127 00 2 ROLLER DETENT 0 125 DIA X 0 125 INCH L 80009 214 1127 00 53 401 0081 02 1 BEARING CAM SW FRONT 80009 401 0081 02 ATTACHING PARTS 54 354 0391 00 1 RING RETAINING 0 395 FREE ID X 0 025 STL 97464 3100 43 CD 55 105 0641 00 1 ACTUATOR CAM TIME CM FRONT 80009 105 0641 00 56 1 IN SEE Al EPL 57 131 0604 00 45 025 SQ X 0 365 INCH LONG 80009 131 0604 00 58 131 0608 00 26 CONTACT ELEC 0 365 INCH LONG 22526 47357 59 stitit ttim 1 TRANSFORMER SEE T410 EPL 60 407 1640 00 1 BRACKET XFMR 0 826 WD 2 375 L 1 781 H 80009 407 1640 00 ATTACHING PARTS 61 211 0507 00 2 SCREW MACHINE 6 32 X 0 312 INCH PNH STL 83385 OBD 62 210 0457 00 2 NUT PLAIN EXT W 6 32 X 0 312 INCH STL 83385 OBD 63 260 1208 00 1 SWITCH PUSH DPDT 71590 2 010000 359 64 361 0573 00 2 SPACER SLEEVE 80009 361 0573 00 65 344 0154 00 4 CLIP ELECTRICAL FOR 0 25 INCH DIA FUSE 80009 344 0154 00 66 136 0514 00 2 SOCKET PLUG IN MICROCIRCUIT B CONTACT 82647 930802 67 136 0269 02 3 SOCKET PLUG IN l4 CONTACT LOW CLEARANCE 01295 c931402 68 136 0260 02 5 SOCKET PLUG IN 16 CONTACT LOW CLEARANCE 01295 931602 69 260 1332 00 1 SWITCH PUSH 80009 260 1332 00 70 361 0385 00 2 SPACER PB SW 0 164 INCH LONG 80009 361 0385 00 131 0993 02 1 LINK TERM CONNE 2 WIRE RED 00779 1 530153 0 131 0993 09 1 LINK TERM CONNE 2 WIRE WHITE 00779
36. RNAL ADJUSTMENT PROCEDURE R155 500 V Ac Gain hc 4 Step 12 Step 15 12 V 4 R175 R215 Floatin 500 V Ac Comp 2V Ac 20 dB tour 6 Adjust Temperature Offset Place the range function switch in the TEMP C position Connect a P6430 probe to the front panel connector labeled TEMP PROBE Place the probe tip in a known environment about 0 C and adjust R270 Offset Adj for a display readout of the probe tip temperature one count 7 Adjust Temperature Gain Without changing the settings from the previous step place the probe tip in a known environment about 100 C Now adjust R280 Gain for a display reading of the probe tip temperature one count Redo step 6 and this step until no interaction exists 8 Adjust F Calibration With the probe tip at a temperature of or near 0 C change the range function to the F position Adjust R268 F for a display reading of 32 F one count If the probe tip is not exactly at 0 C convert the actual temperature in centigrade to Fahrenheit using 9 C 5 32 9 Adjust Ohms Calibration Set the range function switch to the 200 K OHMS position Connect a resistance of known accuracy near 190 kQ to the HI and LO binding posts Adjust R130 Ohms for a display readout of the known resistance one count 10 Check Resistance Ranges Connect resistances of known accuracy approximately 5 below full scale values as shown on the ran
37. TION Replacement parts are available from or through your local Tektronix Inc Field Office or representative Changes to Tektronix instruments are sometimes made to accommodate improved components as they become available and to give you the benefit of the latest circuit improvements developed in our engineering department It is therefore important when ordering parts to include the following information in your order Part number instrument type or number serial number and modification number if applicable If a part you have ordered has been replaced with a new or improved part your local Tektronix Inc Field Office or representative will contactyou concerning any change in part number Change information if any is located at the rear of this manual SPECIAL NOTES AND SYMBOLS X000 Part first added at this serial number 00X removed after this serial number ITEM NAME In the Parts List an Item Name is separated from the description by a colon Because of space limitations an Item Name may sometimes appear as incomplete For further Item Name identification the U S Federal Cataloging Handbook H6 1 can be utilized where possible ABBREVIATIONS ACTR ACTUATOR PLSTC PLASTIC ASSY ASSEMBLY QUARTZ CAP CAPACITOR RECP RECEPTACLE CER CERAMIC RES RESISTOR CKT CIRCUIT RF RADIO FREQUENCY COMP COMPOSITION SEL SELECTED CONN CONNECTOR SEMICOND SEMICONDUCTOR ELCTLT ELECTROLYTIC SENS SENSITIVE ELEC ELECTRICAL VAR
38. TIONS TEMPERATURE Operating 15 C to 40 C Non operating 40 C to 75 C POWER CONSUMPTION 6 5 watts REV A OCT 1974 Section 2 DM 502 THEORY OF OPERATION THEORY OF OPERATION Introduction The DM 502 is basically an analog to digital converter with the logic display devices and power supplies necessary to display in digital form the value of a dc voltage The analog to digital converter is an integrating amplifier Current is measured by passing the unknown current through a known resistance and measuring the resultant voltage drop using a four terminal configura tion Resistance is measured by passing a constant current through an unknown resistance and measuring the voltage drop across the unknown resistance Temperature is measured by obtaining a dc voltage proportional to the temperature and measuring that voltage Ac voltages and currents are rectified and the resulting dc is measured then read out in appropriate ac units The dB circuitry converts the output of the ac rectifier to a logarithmic output that is applied to the analog to digital converter Refer to the Block Diagram in the foldout pages for an overall view of the DM 502 operation Use the following circuit description with the schematics to gain an understanding of the operation of the DM 502 Attenuator and Input Switching The HI and LO binding posts are connected across R147 R146 and R145 serving as a voltage divider The v
39. VARIABLE INCAND INCANDESCENT ww WIREWOUND LED LIGHT EMITTING DIODE XFMR TRANSFORMER NONWIR NON WIREWOUND XTAL CRYSTAL 31 Electrical Parts List DM 502 MFR CODE 00853 01121 01295 03508 03888 04713 07263 07910 14752 15281 15454 15818 17856 18324 19396 27014 28480 34553 49956 50522 56289 58474 71400 71590 71744 72982 73138 75042 80009 80031 80294 81483 86684 90201 91637 3 2 CROSS INDEX MFR CODE NUMBER TO MANUFACTURER MANUFACTURER SANGAMO ELECTRIC CO 5 CAROLINA DIV ALLEN BRADLEY CO TEXAS INSTRUMENTS INC SEMICONDUCTOR GROUP GENERAL ELECTRIC CO SEMI CONDUCTOR PRODUCTS DEPT KDI PYROFILM CORP MOTOROLA INC SEMICONDUCTOR PRODUCTS DIV FAIRCHILD SEMICONDUCTOR A DIV OF FAIRCHILD CAMERA AND INSTRUMENT CORP TELEDYNE SEMICONDUCTOR ELECTRO CUBE INC GENERAL INSTRUMENT CORP DELETED BUSINESS DISCONTINUED RODAN INDUSTRIES INC TELEDYNE SEMICONDUCTOR SILICONIX INC SIGNETICS CORP HEWLETT PACKARD CO CORPORATE SUPERIOR ELECTRIC THE BUSSMAN MFG DIVISION OF MCGRAW EDISON CO CENTRALAB ELECTRONICS DIV OF GLOBE UNION INC CHICAGO MINIATURE LAMP WORKS ERIE TECHNOLOGICAL PRODUCTS INC BECKMAN INSTRUMENTS INC HELIPOT DIV ELECTRONIC COMPONENTS IRC FIXED RESISTORS PHILADELPHIA DIVISION TEKTRONIX INC ELECTRA MIDLAND CORP MEPCO DIV A NORTH AMERICAN PHILLIPS CO BOURNS INC INSTRUMENT DIV INTERNATIONAL
40. W 73138 91A 500ROM R157 321 0292 03 RES FXD FILM 10 7K 0 254 0 1258 91637 1816 70101 R165 301 0104 00 RES FXD CMPSN 100K OHM 5 0 5W 01121 1045 R168 315 0682 00 RES FXD CMPSN 6 8K OHM 5 0 25W 01121 6825 R170 315 0102 00 RES FXD CMPSN 1K OHM 5 0 25W 01121 1025 R172 321 0385 00 RES FXD FILM 100K OHM 1 0 125W 75042 CEATO 1003F R174 321 0978 01 RES FXD FILM 11 02K 0 50 0 125 91637 MFF1816G11021D 175 311 1565 00 RES VAR NONWIR 250 OHM 20 0 50W 73138 91A250ROM R179 321 0287 00 RES FXD FILM 9 53K OHM 19 0 125W 75042 CEATO 9531F R180 311 1563 00 73138 91A 10000M R181 321 0066 00 75042 CEATO 47RSOF R185 321 0193 00 75042 CEATO 1001F R187 321 0193 00 RES FXD FILM 1K OHM 18 0 125W 75042 0 1001 R190 315 0104 00 RES FXD CMPSN 100K OHM 5 0 25W 01121 1045 R192 315 0104 00 RES FXD CMPSN 100K OHM 5 0 25W 01121 1045 R197 321 0276 00 RES 32K 14 0 1258 75042 CEATO 7321F R198 321 0219 00 010100 5019999 RES 87K OHM 1 0 125W 75042 CEATO 1871F R198 321 0202 00 020000 RES FXD FILM 1 24K OHM 19 0 125W 75042 0 1241 R199 321 0219 00 010100 5019999 RES FXD FILM 1 87K 1 0 1258 75042 CEATO 1871F R199 321 0202 00 gt 8020000 RES FXD FILM 1 24K OHM 18 0 125W 75042 0 1241 R200 321 0202 00 020000 RES FXD FILM 1 24K OHM 18 0 125W 75042 0 1241 R203 321 0473 00 RES FXD FILM 825K OHM 18 0 125W 75042 CEATO 8253F R205 311 1554 00 010100 8010369
41. and Q235 Adc voltage whose amplitude is proportional to temperature occurs across C263 The opposite occurs when Q230 and Q235 change state with the exception that Q245 turns on shorting the negative voltage to ground and Q260 is off preventing the discharge of C263 The dc voltage across C263 is applied to operational amplifier U250B R280 adjusts the gain Offset voltage in U250B is compensated for by R270 R268 and R285 through 5110 44 change offset and increase gain for F readout vs C The output of U250B at 10 mV is applied to the analog to digital converter input and the rear interface connectors Clock U325 is a monolithic timing circuit used to generate the clock frequency for the DM 502 The frequency is 20 48 kHz C330 the timing capacitor charges through R328 R329 and R330 and discharges through R330 R328 sets the frequency so that it is a multiple of the power line frequencies This insures minimization of line frequency interference in the analog to digital converter Theory of Operation DM 502 Analog To Digital Converter U290 comprises the analog to digital converter and U335 contains the necessary control logic U290 contains the integrating amplifier comparator auto zero amplifier and input buffer amplifier See Fig 2 2 C300 is the integrating capacitor The clock frequency is divided by the time base counter into groups of 6144 pulses Measurement takes place for 4096 of these pulses a
42. and ac rms indefinitely 250 V and ac rms for one half hour DC AMMETER RANGES 200 A 2 20 mA 200 mA 2 A ACCURACY 0 2 of reading 1 count RESPONSE TIME lt 1 2 8 INPUT IMPEDANCE 0 2 V Range Setting except lt 2 0 on the 200 4A range 010 MAXIMUM INPUT CURRENT ON ANY RANGE Fused at 2 5 A AC AMMETER RANGES Current 200 uA 2 mA 20 mA 200 mA 2 A dB 40 20 0 20 40 Reference is 1 mA dbV or 0 7746 mA dBm 17 Operating Instructions DM 502 ACCURACY Current 0 6 of reading 1 count for a 40 Hz to 10 KHz sine wave Usable to 100 kHz Display Maximum Reading Frequency Range 0 to 20 20 Hz to 20 kHz 0 5 dB 0 to 10 20 Hz to 2 kHz 2 kHz to 20 kHz 10 to 20 20 Hz to 2 kHz 2 kHz to 7 5 kHz 5 kHz to 20 kHz RESPONSE TIME lt 5 5 INPUT IMPEDANCE 0 2 V Range Setting 9 except lt 2 0 KQ on the 200 wA range MAXIMUM INPUT CURRENT ON ANY RANGE Fused at 2 5 A 18 THERMOMETER RANGES Centrigrade 55 to 150 Fahrenheit 67 to 200 ACCURACY With any P6430 probe 8 C or 14 4 F With instrument calibrated to probe 2 C or 3 6 F MAXIMUM INPUT VOLTAGE Up to 1 kV may be safely applied to the front panel INPUT terminals 350 V to the rear input connectors when the range function switch is in the TEMP positions ENVIRONMENTAL SPECIFICA
43. arious capacitors switched across these resistors are the compensating capacitors used in the ac modes of opera tion C100 is switched in series with the divider when the unit is operating in the ac voltage modes R105 R106 R107 R110 and R142 serve as current shunts in the current modes A four terminal technique is used The current passes through the shunts from the HI terminal to the LO terminal The voltage is applied to the analog to digital converter through S110 17 16 9 15 and 18 to ground F100 in series with shunts R105 R106 R107 and R110 along with CR110 and CR112 protect the shunts from over current The diodes conduct opening the fuse before the voltage across the higher value shunts damage them Lamp RT100 protects shunt R142 in the lowest current range and the Ohms Converter REV OCT 1974 Ac Converter In the ac measurement modes the ac signal is applied to fet Q165 CR165 and CR166 protect Q165 from over voltage Q170 connected from the source to the drain of Q165 provides bootstrapping The output of Q165 is fed to the negative input of U195 an operational amplifier A small amount of negative dc feedback is provided by R192 R190 and the filtering action of C190 The gain of U195 is extremely high until CR187 and CR195 conduct This high gain allows rectification of extremely small signals More negative dc feedback is provided through the action of CR187 and CR195 The dc feedback stabilizes the op
44. asured quantity necessary to operate the A tion to seven segment Current and format to drive the display Resistance Temp modules GND Clock Provides 20 48 kHz for the logic functions Ohms Converter Provides constant current to the resistance being measured Display Anode Drivers Activates the appropriat display module Temperature Measurement Converts base to emitter voltage variation in the 25 Vac 12 Power Supply 12 Provides isolated voltages for all Most TEMP PROBE sensing transistor to a dc ture voltage proportional to blocks exnospt lempara 5 Vde Unregulated Significant the Measured tem 25 Vac driver voltage Digit and perature Polarit Display Modules Each module contains seven segments represented as cathodes of light emitting diodes as well as a decimal point The segments are arrang ed to form numbers from zero 0 7 nine When the anode drivers raise the anodes to the un regulated driver voltage the modules are lighted The most significant digit module displays the polarity sign as well as the numeral one 33 Vdc 33 DM 502 CONTROLS AND CONNECTORS Display Readout 3 1 2 digit LED readout with decimal point positioned by range function switch Resolu tion is 0 05 of range except temperature which is 0 1 INPUT Binding Posts Binding posts for application
45. djustment at local Field Service Centers and at the Factory Service Center Contact yourlocal Tektronix Field Office or Representative for further information Refer to the TM 500 Series Power Module manuals for complete maintenance information Test Equipment For calibration and a complete accuracy check of the DM 502 the following equipment is required Digital counter capable of reading to 25 kHz Tektronix DC 504 or equivalent Dc voltmeter 10 20 V Tektronix DM 501 DM 502 or equivalent Dc voltage source to 1 kV Dc current source to 2A Ac voltage source to 500 V rms 40 Hz 1 kHz and 10 kHz Ac current source to 2 A rms 1 kHz Resistances to 20 MQ Temperature source about 0 C and 100 C Accuracy of calibration and performance checks de pend upon the accuracy of the test equipment used Preparation The DM 502 can be calibrated either fully installed in a TM 500 series power module or connected to the power module via a flexible plug in extender Tektronix Part Number 067 0645 01 Remove the power module cabinet to make adjustments to the DM 502 inside the power module DM 502 adjustments are located on the compo nent side of the board Remove the right side plug in cover for access to the calibration adjustments See the accom panying illustration for adjustment locations Make ad justments at an ambient temperature between 20 C and 30 C 68 F to 86 Allow 20 minutes warmup time Rec
46. erational amplifier gain and compensates for amplifier offset voltages or capacitor leakage The positive half cycle is applied through CR195 to the filter network The dc voltage from the filter output is switched to the analog to digital converter input in the ac measurement mode and the dB converter in the dB mode The gain of U195 is set by R180 and R181 to produce a dc output equivalent to the rms value of a sine wave input DB Converter This circuitry converts the linear dc current output from the ac converter to a logarithmic output voltage A collector current change with respect to a base to emitter voltage change in a bipolar transistor is logarithmic VR310 serves as the voltage reference diode at 6 2 V This voltage is applied to the negative input of operational amplifier U210 through R203 and R205 R205 sets the current through Q120A Should the current through Q120A increase the voltage at pin 2 of U210 goes negative This causes the output of U210 to go positive reducing the current through the transistor to the value set by R205 Q120A and Q120B are housed in the same case so that their base to emitter voltages remain constant with temperature for equal collector currents 21 Theory of Operation DM 502 The rectified and filtered dc current from the ac converter is applied to the plus input of operational amplifier U220 through R212 R212 causes a reference currentshift in the dBm mode and is shorted out in the
47. f the LO input is more positive With the input shorted the display reads zero one count 14 CAUTION 3 EAE To prevent possible damage to switch contacts by high currents do not switch into out of or through the current measurement modes from the other measurement modes with a high current source or large inductive or capacitive load connected to the DM 502 input This caution does not apply to Switching between individual current ranges up to the maximum stated input current as the switch contacts are adequately protected for this operation DC Current Measurements Select an appropriate full scale DC mA position on the range function switch Apply the dc current to be measured to the INPUT binding posts A current electron flow into the LO connector and out of the HI connector indicates on display For opposite current flow a will be displayed REV A OCT 1974 AC Voltage Current and Resistance Measurements Select an appropriate full scale AC VOLTS AC mA or OHMS position on the range function switch Connect the unknown voltage current or resistance to the INPUT binding posts Decibel Measurements To use this feature switch to an ac voltage or current range and push the button marked dB on the front panel Connect the voltage or current source to the DM 502 To arrive at the correct dB reading algebraically add the number on the outside scale to the display reading When the dB switch is depres
48. fering circuit Used in the DM 502 Only the Temp Out Temp Gnd and HI and LO inputs are factory wired The others must be installed by the user Sae accompanying illustration for jumper locations lor connections BCD outputs are serialized by digits in an 8 4 2 1 code This code is not valid when the MSD line is high When the MSD and the one are high the fourth significant digit is a one A two may also be encoded as well as overrange information 1 PAGE 1 OF CHANGE REFERENCE _ M23 279 REV 2 11 75 DATE CHANGE 070 1726 00 DESCRIPTION EFF SN 8020000 ELECTRICAL PARTS LIST AND SCHEMATIC CHANGES CHANGE 1 670 3495 01 CKT BOARD ASSY MAIN AL 670 3694 01 CKT BOARD ASSY MAIN OPTION 2 197 290 0536 00 FXD ELCTLT 10uF 20 25V 198 290 0527 00 FXD ELCTLT 15uF 207 20V 199 290 0535 00 CAP FXD ELCTLT 33uF 20 10V R198 321 0202 00 RES FXD FILM 1 24K OHM 1 0 125W R199 321 0202 00 RES FXD FIIM 1 24K OHM 1 0 125W REMOVE C429 283 0279 00 DI 0 001uF 20 3KV ADD C110 283 0279 00 DI 0 001uF 20 3KV R200 321 0202 00 RES FXD FILM 1 24K OHM 17 0 125W A DIAGRAM lt ATTENUATORS amp CONVERSION CIRCUITS Partial suo 3 3200 3 peso 5 Voie Tren AR Ross B PIV
49. ge function switch to the HI and LO binding posts Check that all OHMS ranges are within specified accuracy 11 Check DC mA Ranges Apply accurately known currents approximately 5 below full scale values as shown on the range function switch to the HI and LO binding posts Check that all DC mA positions are within specifications 12 Adjust AC Voltage Calibration Set the range function switch to the 2 AC VOLTS position Connect an accurately known ac voltage near 1 9 volts rms at 1 kHz to the HI and LO binding posts Adjust R180 2 V Ac fora DM 502 display reading of the applied voltage one count Now Switch the range function switch to the 200 MV AC VOLTS position and apply an accurately known voltage near 190 mV to the input terminals Adjust R175 2 V Ac fora display reading of the applied voltage one count 13 Adjust 20 V AC Compensation Set the range function switch to the 20 AC VOLTS position Connect a known ac voltage near 19 volts rms ata frequency of 1 kHz to the HI and LO binding posts Adjust C150 20 V Ac Comp for a display reading of the applied voltage one count Now switch to the 200 AC VOLTS position and apply an accurately known ac voltage near 190 volts rms Check that the display reading is the applied voltage within specifications If not redo this step slightly com promising the adjustment in the 20 AC VOLTS position until both readings are within specifications 14 Adjust 500 V AC
50. he integrator output is open See Fig 2 3 for functional timing during the auto zero interval Notice that the fifty percent duty cycle of the up down counter is overridden at the start of the auto zero interval This override period permits the output of the integrator to come to Vun and C316 to assume this voltage Upon completion of the 2048 clock pulse auto zero interval the measurement interval commences The measure zero logic switches the analog input voltage to the buffer input and disconnects the integrator output from the auto zero amplifier input The additional current resulting at the summing junction of the integrator causes the integrator output voltage to move away from the equilibrium voltage obtained during auto zero interval and maintained during the measurement interval by C316 The comparator senses and transmits this deviation to the control logic The contro logic changes the duty cycle of the reference voltage in an attempt to re establish equilibrium at the integrator summing junction The up down logic is up integrator output voltage is also up for one clock cycle and down for seven cycles when the comparator output was high during the preceding set of eight clock cycles This is shown as duty cycle A in Fig 2 4 When the comparator output is low in clock cycle seven the up down logic is up for seven cycles and down for one cycle during the following eight clock cycles This is shown as duty cycle B Fig 2 4 show
51. he surface Allow sufficient time for the probe tip to stabilize before taking a reading The time required depends upon several factors Generally when the tip is first applied to the device under test the readings change rapidly As the probe tip temperature approaches the temperature of the device under test the readings change less rapidly and finally stabilize The readings are in C or F depending on the position of the range function switch See the P6430 manual for more informa tion on temperature measurements and probe use Using a Transistor as a Temperature Sensing Device Certain npn transistors such as a 2N2484 can be used as separate sensors in place of the P6430 probe with little or no selection of the transistor Connect the temperature sensing transistor to the DM 502 through the TEMP PROBE connector as shown in Fig 1 4 Accuracy without recalibration of the DM 502 is within 8 C to 150 C Ifthe Connector shell Sensing Transistor 2N2484 Connector TEKTRONIX Part Number 131 1653 00 Fig 1 4 Schematic diagram of temperature sensing transistor connected to probe connector Operating Instructions DM 502 measurement to be made requires greater accuracy recalibrate the temperature circuitry or determine a correction factor Place the sensing device in an environ ment having a known ambient temperature Use any difference between the known temperature and the DM 502 readout as a correction factor th
52. hrough the three wire power cord False readings may be obtained due to ground loops If the INPUT button is pushed in signal inputs are made via the rear interface connector if the button is out signal inputs are made via the front panel Functions Avallable at Rear Connector HI LO GROUND temperature output at 10 mV per degree and bcd connections are available at the rear 1 2 interface connector The Rear Interface Connector Assignments page in the Service Section at the rear of this manual gives data on the various connections Only the Temp Out Temp Gnd and HI and LO inputs are factory wired Jumper holes are provided for making the desired bed output connections See the wire locations illustration in the foldout pages for the correct circuit board locations Simply insert and solder an insulated wire strap in the proper locations Buffers are required before the data outputs are used to drive external loads See Fig 1 3 fora typical buffer circuit The DM 502 has a slot between pins 17 and 18 A barrier in the corresponding position of the power module jack allows only compatible plug ins to be used in that compartment This protects the plug in should specializ ed connections be made to that compartment Consult the Building A System section of the power module manual for further information FET input jumper position 10 MQ Input jui postion Operating Instructions DM 502 reverse of board as shown
53. imum input voltage is 1 kV 350 V at the rear connectors The front panel HI and LO connectors may be floated 1 kV maximum above ground the rear inputs 350 V Installation and Removal The DM 502 is calibrated and ready for use when received It operates in any compartment of a TM 500 series power module See the power module instruction manual for line voltage requirements and power module operation Fig 1 1 shows the DM 502 installation and removal procedure Turn the Power Module off before inserting the DM 502 Otherwise arcing may occur at the rear inter lace connectors reducing their useful life and damage may be done to the plug in circuitry Check that the DM 502 is fully inserted in the Power Module Pull the PWR switch on the Power Module One or more characters in the LED display should now be visible The Controls Connectors and Adjustments foldout page in Section 3 gives a complete description of the front panel Operating Instructions DM 502 Fig 1 1 DM 502 Installation and removal OPERATING CONSIDERATIONS Input Connections Three binding posts provide measurement connec tions The HI and LO posts are normally used for all measurements except temperature Normal measurement conditions will be with the LO terminal ungrounded A connection between the LO and GND posts may be made to reference the input against DM 502 chassis ground Use caution as the LO terminal is then connected to earth ground t
54. iplexed to the data output buffers The data output format is an interlac ed scan of digits one three two and four Four is the most significant digit With a count of 2000 or greater in the counter 100 of full scale the 3 1 2 digit display blinks off during the zero cycle e Power Supplies The entire DM 502 circuitry with the exception of the temperature circuitry can be elevated up to 1kV above chassis ground Isolation is accomplished with transformer T410 50 V ac from the power module two 25 V ac windings in series is applied to the transformer primary Ac for the 5 V and 12 V supplies is bridge rectified U420 for the 12 V supplies is a dual tracking voltage regulator R418 is a current shunt for the 12 V supply and R427 is the same for the 12 V supply R422 sets the levels U420 is internally protected against short circuit damage Power for the display modules is not electronically smoothed regulated or filtered 0440 serves as the series pass transistor for the 5 V supply The output voltage is set through the divider consisting of R452 and R453 connected to the base of Q450 Should the 5 V output drop Q450 increases conduction This causes Q440 to also increase conduc tion restoring the output voltage to the preset level The temperature measuring circuitry obtains 15 V from 33 5 V through zener diodes VR400 and VR405 25 Section 3 DM 502 REPLACEABLE ELECTRICAL PARTS PARTS ORDERING INFORMA
55. n specifications To 14B Polarity Paci LOCATIONS FOR USER WIRED To 26A 3rd SD REAR INTERFACE CONNECTIONS To 25A LSD To 19A BCD 1 To 20A BCD 4 Component side B E To 27B Decimal lt ws To 15B One s To 218 BCD 2 208 BCD 8 e To 19B Transfer To 27A Common DM 502 REAR INTERFACE CONNECTOR ASSIGNMENTS Maximum Maximum Recom Recom mended Active output or Pin Output or Active mended Remarks Loads Level Input A Input Leads Remarks HL Input 28 to input Floating Decimal 5 gl Common Out Use as common for all data outputs MSD Our 25 ard 50 Out g End SD Out 25 25 LSD out 7 Chassis TO VT Temp Gnd 24 24 Temp out mio zl 22 22 sep ours a 21 H BCD Out 8 20 BoD Out Transfer 39 eco Outi Barrier Slot Mutiplexed e 7 Polarity na 14 14 725 VAC 25 VAC winding __ 73 13 winding 3335 V __ 12 Collector Base lead of PNP 11 11 ead ot PNP Series Pass Series Pass Emitter Transformer iot shield 10 7835 V n common slot Bi Not Used 6 6 lead of NPN Series 175 VAC 17 5 VAC winding winding FSV common common 115 11 5V common common 11 5V
56. nce is dBV 1 V or dBm 1 mW dissipated in 600 Q 0 7746 V ACCURACY Voltage 0 5 of reading 1 count fora 40 Hz to 10 kHz sine wave 1 0 of reading 1 count for a 20 Hz to 20 kHz sine wave Usable to 100 kHz Typically lt 10 down between 40 mV and 500 V at 100 kHz REV OCT 1974 DB Display Frequency Maximum Reading Range O to 20 20 Hz to 20 kHz 05 0 to 10 20 Hz to 2 kHz 0 5 dB 2 kHz to 20 kHz 1 0 dB 10 to 20 20 Hz to 2 kHz 0 5 dB 2 kHz to 7 5 kHz 1 0 dB 7 5 kHz to 20 kHz COMMON MODE REJECTION 60 dB at 50 or 60 Hz with a 1 unbalance RESPONSE TIME lt 5 8 IMPUT IMPEDANCE 10 MQ 1 paralleled by lt 60 pF MAXIMUM INPUT VOLTAGE ON ANY RANGE Front Panel 500 V ac rms or 56 dBm or 600 V de not to exceed 1 kV plus peak ac Rear Connector 350 V plus peak ac or 50 dBm OHMMETER RANGES 200 Q 2 20 200 2 20 ACCURACY 200 Q range 0 5 1 count 0 1 Q 2 through 2 ranges 0 5 1 count 20 MQ range 1 0 1 count REV A OCT 1974 Operating Instructions DM 502 MEASUREMENT CURRENT AND VOLTAGE Range Current Full Scale Voltage 200 Q 1 mA 0 2 V 2 1 2V 20 KQ 100 uA 2V 200 10 uA 2 2 THA 2V 20 MQ 0 1 uA 2V RESPONSE TIME 200 Q through 2 MQ ranges 1 2 s 20 range lt 55 MAXIMUM INPUT VOLTAGE ON ANY RANGE 130 V de
57. nd automatic zeroing takes place for 2048 pulses The auto zeroing feature provides current to compensate for offset currents in the buffer amplifier Basic sensitivity of the analog to digital converter is 2 V for a full scale display reading When S110 36 is closed the sensitivity becomes 0 2 V full scale During auto zero the input of the buffer amplifier is grounded The buffer offset currentalso offsets the output ofthe integrator Theoffsetatthe integrator output passes through a low pass filter comprised of C300 R300 and R302 to the plus input of the auto zero amplifier The output of the unity gain auto zero amplifier compensates for this offset current at the summing node pin 9 at the integrator input The reference current through R304 and R305 from the reference current source is applied for four clock cycles and disconnected for the next four cycles by the U D control logic The reference current is connected to R304 when the up down logicis low Equilibrium for the Fig 2 2 Analog to digital converter and control logic block diagram Reprinted by permission of Siliconix Inc REV A OCT 1974 23 Theory of Operation DM 502 entire integrating and auto zero system is obtained when the sum of the average currents the integrator summing junction equals zero C316 charges to the equilibrium voltage and maintains this voltage at the auto zero amplifier input during the measurement interval when the switch from t
58. nt Rear interface connector input is also pushbut ton selected from the front panel Values of dB are obtained by adding the selected dB range value to the display reading Readout in dBm or dBV is chosen by an internal jumper The unit is shipped with the jumper in the dBm position An internal jumper also permits selection of fet input gt 1000 MQ or 10 input impedance on the two lowest dc voltage ranges The unit is shipped with the jumper in the 10 MQ position See Fig 1 2 Temperature measurements are made using a Tektronix P6430 probe Tektronix Part Number 010 6430 00 or other suitable sensing devices Option 2 in struments delete the temperature measuring capability The readout is a 3 1 2 digit display using seven segment LED s The decimal point is automatically positioned by the range function switch Polarity indica tion is automatic A usable 50 overrange exists in all measurement modes except ac voltage and current 1000 V dc and the 2 A dc current range In overrange the display blinks and the most significant digit is suppressed Upon exceeding the available 50 overrange a 1 appears in the most significant digit position Display readings are invalid beyond this point REV A OCT 1974 Interlaced bcd output 1 3 2 4 referenced to the low input is available at the rear interface connector if user wired NOTE The DM 502 is not directly compatible with the 153 Calculator Interface The max
59. of unknown voltage current resistance May be floated 1 kV above ground Ground Binding Post Chassis Ground TEMP PROBE Connector Mates with P6430 probe con nector Also used with other temperature sensing devices DM 502 DIGITAL MULTI METER ADD TO DISPLAY IN dB MODE Range Function Switch Selects all ranges and functions dB Button in selects dB readout in ac modes INPUT Pushbutton Button OUT transfers input to front panel Button in rear inter face connector Does not switch TEMP input corsa korua N otzuo sezo bey d ae S920 K MSE COMPONENTS SHOWN WITH DASHED LINES ARE LOCATED ON BACK SIDE OF BOARD NOTE CKT GRID CKT GRID CKT GRID CKT GRID NO Loc NO Loc Loc NO Loc C100 D4 CR334 2 R172 F5 R334 E2 VR120 HS C120 H6 CR410 J6 8174 F5 8340 J1 VR270 M2 C130 E6 CR430 14 8175 F5 R341 J1 VR300 B1 C142 B3 CR435 14 R179 F6 R342 J1 VR310 A2 C146 A4 R180 E6 R343 J1 VR400 L6 C150 B4 R181 F6 9344 J1 VR405 16 C151 C4 DS350 K7 R185 F6 345 J1 C152 B4 DS355 K7 R187 F6 R346 K1 C154 05360 J7 8190 ES R349 n C155 cs DS365 J7 R192 F6 R350 C157 85 8197 F6 354 n C158 BS R198 F5 R355 n C168 F5 F100 C3 R199 F5 359 n C170 E6 R203 G5 R360 n C175 F5 R205 HS R364 H1 C190 E6 J250 R208 H5 R365 H1 C192 E6 R210 G5 R369 G2 C195 F6 R212 G5 R370 G2 C197 FS P100
60. ommended recalibration interval is every six months Sometimes overall accuracy of the DM 502 on ranges affected by a specific adjustment may be improved by compromising the adjusment within specifications from the exact setting called for in this procedure Checks and Adjustments 1 Check Power Supply Voltages Using the dc voltmeter at the points shown on the illustration check the power supplies for 5 V 0 1 V and 12 V 0 6 V 2 Adjust Clock Frequency Connect the counter input to the point labeled clock in the accompanying illustra tion Adjust R328 Clock for a frequency of 20 48 kHz 0 2 kHz 3 Adjust Integrator Zero Set the range function switch at the 2 DC VOLTS position Short the HI and LO input binding posts together Adjust C315 A D Zero fora display reading of all zeros one count 4 Adjust DC Calibration Apply a known dc voltage near 1 9 V to the HI and LO binding posts to the HI post Make certain the range function switch is in the 2 DC VOLTS position Adjust R305 2 V Dc fora display reading of the applied voltage one count Change the applied voltage to about 0 19 V and the range function switch to the 200 MV position Adjust R295 2 V Dc to display the applied voltage one count 5 Check DC Voltage Ranges Apply known voltages approximately 5 below each full scale value on the range function switch to the HI and LO binding posts Check that all ranges are within specifications INTE
61. roughout the entire measurement range Accurate Current Source The OHMS positions on the range function switch provide accurate typically 0 2 constant currents at the INPUT terminals See the Ohmmeter specifications for the value of the currents and maximum voltages across the INPUT terminals for full scale display readings The maximum voltage available across the INPUT terminals in the OHMS position is about 10 volts ELECTRICAL SPECIFICATIONS Performance Conditions The electrical characteristics are valid only if the DM 502 has been calibrated at an ambient temperature between 20 C and 30 C and is operating at an ambient temperature between 15 C and 40 C Warm up time to specified accuracy is twenty minutes Display The measurement rate is 3 33 per second Resolution on all ranges is 0 05 of full scale setting except for temperature which is 0 1 DC VOLTMETER RANGES 200 mV 2 V 20 V 200 V 1000 ACCURACY 0 1 of reading 1 count COMMON MODE REJECTION 2100 dB at dc 80 dB at 50 60 Hz with a 1 unbalance NORMAL MODE REJECTION gt 80 dB at 50 60 Hz 1 6 STEP RESPONSE TIME lt 2 s INPUT RESISTANCE 10 0 25 jumper selectable for gt 1000 on 0 2 V and 2 V ranges MAXIMUM INPUT VOLTAGE ON ANY RANGE Front Panel 1 kV Rear Connector 350 V AC VOLTMETER RANGES Voltage 200 2 V 20 V 200 V 500 V dB 40 20 0 20 40 Refere
62. s the result of these actions on the integrator output A counter synchronous with the up down logic in crements by each clock pulse when the up down logic is up and decrements by each clock pulse when the up down logic is down The net count increases by six counts for each B duty cycle and decreases by six counts for each A duty cycle to a maximum count of about 3100 This counting procedure is reversed for negative input voltages Polarity of the input voltage is determined by the state of the up down logic when the bcd counter state is zero This information is stored in a flip flop and loaded into the static latch once each measure zero cycle The bcd counter accumulates a number of counts proportional to the input voltage during the measure interval while the control logic works to maintain equilibrium It can be seen that equilibrium is achieved in steps and usually a residual voltage remains at the end of the measurement cycle This residual voltage is compen sated for by ashort override interval at the beginning of the auto zero period The counter continues until the in tegrator output equals the auto zero equilibrium voltage and the up down logic is down The bcd counter is now put on hold and its contents loaded into the latches The counter is then cleared Fig 2 3 Auto zero timing intervals Reprinted by permission of Siliconix Inc 24 Theory of Operation DM 502 s nnnm ru M T ir ec y 373 4 8
63. sed the decimal point is fixed and the maximum display reading is 19 99 on all scales For example if the range function switch is on the 2 AC VOLTS position and the display reading is 13 98 then the correct dB reading is 13 98 20 00 6 02 dB If the range function switch is on the 200 AC mA position and the display reads 4 04 then 4 04 20 00 15 96 dB Selection of dB readout dBV or dBm is accomplished by a jumper shown in Fig 1 2 The reference for dBV when measuring ac voltage is one volt and when measuring current one milliampere The reference for dBm in the voltage range is one milliwatt dissipated 600 Q or 0 7746 volts in the current measuring range the reference is 0 7746 milliamperes When dBm or dBV is applied to current measurements they have no significance other than to the reference current as stated above Useful dB formulas are 20 logio and 1010940 dB 20109 REV A OCT 1974 Operating Instructions DM 502 For calculations substitute the reference voltage or current listed as the denominator Temperature Measurements With the P6430 probe connected to the front panel connector labeled TEMP PROBE set the range function switch to the F or C in the TEMP position Apply the probe sensor tip to the device being measured For optimum temperature transfer coat the surface of the device being measured with silicone grease and apply the probe tip squarely to t
64. to hard wire in F range CICCO a RS dBV jumper position Fig 1 2 Locations of dB reference jumper input impedance jumper and hard wired C or F component or wire changes Sine wave Response The DM 502 responds to the average value of a sinusoidal current or voltage The readout indicates the equivalent rms value The effective or rms value of a sine wave is 0 707 times the peak voltage or current The average value is 0 636 of the peak value The scale factor of the DM 502 is 0 636 0 707 or 0 9 Multiply the DM 502 readout by 0 9 to obtain the average value of a sinusoidal input voltage or current Temperature Measurements Connect the P6430 or other sensing device to the connector marked TEMP PROBE Use care to align the connector pins properly Select calibration in F or C with the range function switch For best accuracy calibrate the individual instrument to the probe used See the Internal Adjustment Procedure in the service section of this manual for the proper procedure 1 3 Operating Instructions DM 502 Output 2N3565 or other transistor with minimum beta of 150 Fig 1 3 Typical buffer circuit for rear connector data outputs Up to 20 mA may be used from the DM 502 5 V supply The Temp Out terminals at the rear interface connector are always connected to the output of the temperature circuitry This feature provides continuous temperature monitoring capabilities in

Tektronix Video Game Keyboard 502 User's Manual

Contents

Download Pdf Manuals

Related Search

Related Contents