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Tektronix 7A18A User's Manual

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4. DISPLAY MODE SELECTED CH 1 ALT ADD CHOP CH 2 Level is switched between the Hidevel and LO levet at an approxi 0 5 megahertz rate Y is switched between the Hi level and LO level at rate determined the setting of the time base unit sweep rate 1125 46 Fig 3 3 0270 input combinations for DISPLAY MODE selection the signals from both channel 1 and channel 2 are passed to the Signal Output stage This condition occurs only when the DISPLAY MODE switch is set to ADD in this operating mode the signal output is the algebraic sum of channel 1 and channel 2 signals and the resultant signal determines the mainframe deflection Trigger Channel Switching The Trigger Channel Switch J470 is identical to the Sig nal Channel Switch This stage determines which input CH 1 or CH 2 provides the trigger signal for internal triggering of the time base unit The selection of the trigger signal is controlled by inputs from the TRIGGER SOURCE switch Resistors R476 R477 and R576 R577 set the current gain for each channel Networks C474 R474 C475 R475 and C574 R574 C575 R575 provide high frequency compensa tion for each channel n input output table for this stage is shown in Fig 3 4 When the level at pin 14 is LO the output of U470 is deter mined by the level at pin 4 With the level at pin 14 H and the level at pin 4 LO the Channel 1 and Channel 2 triggers are added algebraicall
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6. DC ouput and set the input coupling switch to DC OFFSET c CHECK Using the OFFSET control check that the trace can be returned to graticule center d Set the standard amplitude calibrator for a minute one volt DC output e CHECK Using the OFFSET controk check that the trace can be returned to graticule center CIRCUIT DESCRIPTION DC levels of up 200 divi sions can be offest by switching the input coupling to DC OFFSET and using the OFFSET control In the DC OFFSET mode the selected offset voltage from OFFSET control R12 R22 CH 2 is applied to the base of Q320 0520 CH 2 through current limiting resistor R320 R520 CH 2 This additional bias voltage is used to balance the differential in put of Q220 0420 CH 2 LED s are inserted in series with both CR220 and CR221 CR420 CR421 CH 2 to allow a larger voltage swing at the base of Q220 0420 2 See Fig 6 2 for a side view of the 7A18A Option 06 See Section 9 for the exploded view and mechanical parts list The schematics of the Option 06 circuits are shown in Section 8 Option Information 7A18A ver ither Option 06 or standard 7A18A e 1 lt 5 won 5 E 5 9 gt 8 C 4 S 4 e N 4 2 5 gt gt e 1 85 ic 2 272 6 3 P 00456 4
7. THO RU a 127 97 v gt Tau 9b TY VC 93 Y HO Soars 35330 N SIVL PH2 Q OPTION 6 CHANNEL 2 INPUT AMPLIFIER P O A2 ASSY Option 6 2 Input Ampl lt gt Circuit Schematic Circuit Schematic 1 Number Location Number Location i EEE A NOE 8422 ES R423 C5 R424 C5 R425 C7 R426 4 8427 C5 R428 05 R429 05 R436 ES R440 24 R444 F3 R442 G2 R443 F3 R444 F5 R445 4 8446 FS R449 G4 R450 L5 8451 13 R455 KS R456 K3 R459 L5 R460 15 R463 L2 R464 L2 8513 B3 4518 8519 8520 88 R521 B7 R522 C7 8523 08 8524 C5 R525 C3 R526 EG 8527 C6 8529 05 R540 F5 R541 F7 R542 G7 R543 F7 R544 G7 8545 F4 R549 H6 R550 L5 R551 L6 R555 K7 R556 K7 8557 R559 L5 8563 L7 R564 17 P O A2 ASSY also shown on Option 6 2 Input 8675 H5 R676 R677 R679 R681 5667 U675A 06758 OPTION 06 CHANNEL 2 INPUT AMPLIFIER gt 96 435 AS 949911 1 VMV LOdNI 7 90 NOILLdO Li 61 1904 7 y x PER 3 3o 53 y Sar es 1992 eres 138330 phax S ee CX5 Tasi
8. ATTENUATORS dW Ada D 60 01 8 9511 Sped SZ Jo pus quiassy AALY Sueuoduo2 Pajunow Sisseud pasn saquin 41 usse a lt gt Aiqwassy EE CV ogun 1N3N0dW02 LIN 1011998 eoueuajuiey 996 8 IM 0 eAnisues 211815 OQ ous OL 1 OL 492 1090 v E A1102912 bio 075 AIG SLIOA 50 aN9 2v 0 A 51 4 Gais H2 109 T vu QJ 189 92 VIV 2851 50 i l i 49801 pe DITA OL LONI I HD I 1 I i NA O E u e y ar oT 1 oD ME EN 9 i rm 9 5 1 101 i g Tj Im E N g E t 1 s 5 ie E 1 4 5 v a a EXHI VOOIG B g g AU 05 a a E a a o E 6 O Nado 9 E
9. 4042907 uone2o pieog opeusyos 7 lt gt A jquiessy peog 72 8 CL 875V Lnoavau eviv V9IV READOUT lt gt 4 Rin belit 3511 sued Sigea2ejday 10 pus eas x jaid 8 1889I M Alqiuassy pajulour sisseu RE guessegng 11011988 eoueuojuit 88 CU SAAI III5V2 CV EZY o it gun TIdWVX3 LNINOINOO SED 302 185 DEN b 8 0795 der 173 11 gt dom uen 22 A mem X o sa mona 1995 89942 IED 95932 aq lt gt eb Hp 8544 di Ay Le 294 mL Moa 1991 459 yea 93 719 8 L 945 Bee MOA a Lj 15 3981 0994 CNEA ULE yo ovo 9 92 nn y auos E LOOGVS uty PRESA CUB
10. i 2153 ALY 987 7 lt VA f 0975 is var 873 5 CERO 3 Ast 51224 INIA je pue sas 180MI0M Ajquiasey sjuabadumo pase Ji Afgjulassegno OGM Argwassy 4 H H H i ZW EZ Yen mu 4910009 YIQWAN 183804802 0128 895 K I 0 anisuas ones iy 1294 Y 1298 E LL 995 LM 029 1 LL V7995 029 HA 99 Brod LM 9230 LW 8V99 0290 LI 44 47983 LI 4798 CI 43 21 17 93 groti 0794 3 A qvod 9 CI 99 rou I 89 21 829 Zi 94 2793 21 21 99 1994 i1 87380 CI 87940 i LL p349 4 e orgy 22940 1 42 6593 i1 179490 d SE 5534 Hoto Zi 1 43 8298 17 66992 3 Zi 65952 21 43 4598 LI 82980 1 42598 8E9HO 5 21 3 9 92940 1 21 5C9 92980 21 29 11 VEO 1 CI 7699 2 12291550 CM 4 5594 12980 2 2298 2940 CM 1294 IM 02380 j CM 295 02980 42 0099 LM 12 12982 i 17 GO 62949 17 6294 i eM 49 DA 2 Go 1290 SLE UI GER enn 2 Eee 0123071 10189907
11. 8 2 c CHECK With the VARIABLE control fully counter clockwise check for two divisions or less of deflection d Return the VARIABLE control to the CAL IN position e Change the following control settings DISPLAY MODE CH 2 CH 2 AC GND DC DC f Repeat parts b c and d of this step for Channel 2 4 Check Channel 1 and 2 Trace IDENTIFY Center the crt display vertically with the 7A18A POSI TION control b CHECK Press the IDENTIFY button and check that the trace moves upward Set the DISPLAY MODE switch to CH 1 and repeat parts a and b of this step for Channel 1 d Disconnect all test equipment 5 Check Channel 1 and 2 Upper Bandwidth a Connect the medium frequency constant amplitude sine wave generator to the 7A18A CH 1 input connector with the 42 inch BNC cable and in line 50 ohm BNC termination b Set the medium frequency generator for an eight divi sion display 80 millivolts at the 50 kilohertz reference frequency Increase the generator frequency until the display am plitude decreases to 5 6 divisions d CHECK Generator output frequency must be at least 75 megahertz e Disconnect the generator output from the CH 7 input connector and connect it to the CH 2 input connector f Set the DISPLAY MODE switch to CH 2 g Repeat parts b c and d of this step for Channel 2 4 5 P ITAM 2 E h
12. Y e a n e me 41N2IdN Lod Paaa pua XII316 04 pajuod ssseq Ji JOQUAN 199010 Apquiasseqns Aquiassy 25 EZY 3idWVX3 1N3NOdINOO lt 8 gt uo osje ASSY EYLY O d uoioag eoueuosjuiey 995 se3iAeg eAnisues 211615 0 II IV 71 8 10 6259 id vOCH 4 id 2 29289 29 29 4628 P 23 CI SIEH 23 lee moe eme een ten s 23 ZA 1954 2H 2 etes T LA 2H 28 2 21 e 13 91 ev uS 95 gt 155 3 23 22 95 T __ 2 LINES 4 93 Grey 2 998 11 b cs PET 13 13 grey 23 IM p 14 20 7 p t 13 49 evt ld vo z ba s a i3 3 2 yt P b en d 13 54 5 E IN T 29 1253 10 19 LE 93 9264 CI 3 X 15 3253 23 21 PU NE gt 5 7253 24 79 E 19 80 EZEH Z4 21 2 LD 42 2264 29 en ae 2 19 LZEH 29 0055 ES 8g 0204 29 522 59 VO 24 29 22 13 ELEH 24 e
13. GHD 1 35 O ws LC 3345 52 MM ew D 40065 0740 TAgit 4013985 995 151 seg PONPA Ageadejday jo pus 225 24 94115498 2488 K quiaessy 0 GARY 34091 PAUROW SISSEY fpssn JOQUAN s a 1 PEZTA ev CCV Jagun 100 q OENE 182 15 LU 1 OSL 29 E E L32ANI 1 Gf OLD OL 23494 ioo Da NEL 1915 erya AOS Sur C C TASIE uoa Tas ae 550 Obs ANN gm m 2 LIGA 02756 0270 OL Ye NNDS 11931195 Lor ra 8794 91 FIX Bird Lovag ITA Eva WORE haa Nagi TH Section 9 7 18 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 inform
14. 1126 43 Fig 2 5 High resolution phase measurement using time base magnifier Fig 2 4 but with the Magnifier set to X10 With a horizontal difference of 3 divisions the phase difference is horizontal magnified Phase Difference difference X sweep rate divisions degrees division Substituting the given values Phase Difference 3 X 4 5 The phase difference is 13 5 Common Mode Rejection The ADD feature of the 7A18A can be used to display signals which contain undesirable components These unde 2 7 9 ur nr a Operating Instructions 7A18A sirable components can be eliminated through common mode rejection The procedure is as follows i Set the DISPLAY MODE switch to ALT or CHOP and the TRIGGER SOURCE switch to MODE 2 Connect the signal containing both the desired and undesired information to the CH 1 input connector 3 Connect a signal similar to the unwanted portion of the CH 1 signai to the CH 2 input connector For example in Fig 2 6 a line frequency signal is connected to Channel 2 to cancel out the line frequency component of the Channel 1 signal 4 Set both coupling switches to the same setting DC or AC depending on the applied signal 5 Set the VOLTS DIV switches so the signals are about equal in amplitude 6 Set the DISPLAY MODE switch to ADD Set the CH 2 POLARITY switch to INVERT so the common mode signals are of opposite po
15. I0 syuauodiso2 oggy 7893 04295 895 NUR 3 5 pasa ji S89 AGG 94115495 313835 Ajquiassegng SU AS C 4 Agqwassy Y ste L i Jequiny 6914 ico T Yid NVX3 9419MIIM ININOJNOI i 7 Melk aaa 8 lt OL GEES EDO EN AG 1 16 Nid OL Ioo 98125 Y TA GED an LOLI OL T343 AYNDIG 3c TH 97 1 om Sa 94 ASI A9 ics at Lera if 9v SE amp vos 1 99 OL fe Qu a m 9794 01 AA THD L5 98874 ul t TH AOL gt gt TWNSIS gt LGN PND 9 8 lt gt uo umous osje ASSY YLY Old 89491 vS49n gt ASSY VLV Old 5 gt lt gt lt gt lt gt uo umoys osi ASSY ZY Old 7990 EOGH 1454 9558 9994 9989 0934 9799 prou 5754 Sd 6253 1299 9298 9224 vos 1248 0254 6 55 8158 2198 12244 5975 0925 Sapt L5V 0373 524 4442 ivy Orr 9573 6273 Lov
16. 2 RR ANE lt x 52 2 2 25 T 2 2522552 5 5 RU 52 RE 2 225250 MOS aS 7 SES 5 ESTES S ASS 524 552206 225 5 55025 55 c m A ER 2 2 VADE 34 2 2 8 26 2 SEELE B 2 G FA 00 RER 2 25225 2 2 2 S OU 2 BR gt ESEL ITS ONE NIE 9 AR 2 2 25255 IA 5 522 5555 26 5 2 55 amp BR 25 227 252 NE 52 222 2524 DER ENTE 25574 2 EIERN RR 2 ORS ER RER 222 5 2 gt gt 2552 5557 NEE LESA gt SELL 2500 2520 BR 2 v EI 05722665555 BR 555 2 SER 22 2 55756 RER CORRE 542 ER D gt 58 5452 1 22 SENA 72 SE RER DS 20 22 EN 3 2255 2 9 x 2 5 m 4455 EBEN 255 22 SE SURES 05 50225 3 gt 502 2 QE IX ESS 52022 gt 52 5 522 E 5 gt gt gt EN ASS lt lt 202 BERG 92 SOS 2 WERE re 25525206 AS CIRCUIT DESCRIPTION Introduction This section of the manual contains a description of the eircuitry used in the 7A18A Dual Trace Amplifier The de scription begins w
17. KNOB GRAY 80009 366 1077 00 213 0153 00 2 SETSCREW 5 40 X 0 125 BK OXD HEX 000CV ORD BY DESCR 3 366 1059 00 2 PUSH BUTTON GRAY 80008 366 1059 00 E 131 0679 02 2 CONNECTOR RCPT BNC MALE 3 CONTACT 24931 284R270 1 fee ATTACHING PARTS ttt 5 220 0497 00 2 NUT PLAIN HEX 0 5 28 X 0 562 INCH HEX BRS 73743 ORD BY DESCR 6 210 1039 00 2 WASHER LOCK INT G 521 ID X 0 625 INCH 24931 ORD BY DESCR PARTS 5 7 366 1308 00 2 80009 366 1308 00 213 0153 00 2 SETSCREW 5 40 X 0 125 STL BK OXD HEX 000CV ORD BY DESCR 8 366 1058 83 1 KNOB LATCH GRAY 80008 366 1058 83 temer ATTACHING PARTS u 2 9 214 1095 00 1 PIN SPG SPLIT 0 094 OD X 0 187 INCH LONG 22599 52 022 094 0187 END ATTACHING PARTSy 7 10 105 0076 04 1 RELEASE BAR LCH PLUG IN UNIT 80009 105 0078 04 41 366 1163 00 1 KNOB LIGHT GRAY 80008 366 1163 00 213 0153 00 1 SETSCREW 5 40 X 0 125 OXD HEX 000CV ORD BY DESCR 12 214 1280 00 1 SPRING HLCPS 0 14 OD X 1 126 L 0 16 D A 80009 214 1280 00 18 366 1165 00 1 KNOB GRAY 80009 366 1165 00 213 0153 00 2 SETSCREW 5 40 X 0 125 STL OXD HEX 000CY ORD BY DESCR 14 366 0215 01 8010100 8012129 2 KNOB LEVER SWITCH 80009 366 0215 01 366 0215 02 8012130 2 RES FXD CMPSN 220 OHM 5 0 25W 01124 CB2215 15 366 1299 00 2 KNOB GRAY 80009 366 1299 00 213 0153 00 4 SETSCREW 5 40 X 0 125 STL BK OXD HEX 000CY ORD BY DESCR 16 214 3369 00 2 SPRING GROUND 80009 214 3369
18. CAP VAR PLSTC 0 25 1 5PF 600V RES FXD CMPSN 1M OHM 5 0 125W RES FXD FILM 1M OHM 0 526 0 25W SW CAM ACTR ASSY VOLTS DIV ACTUATOR CAM SW AC GND DC DC OFFSET ACTUATOR CAM SW ATTEN ACTUATOR CAM SW AC GND DC DC OFFSET ACTUATOR CAM SW ATTEN 7 3 Mir Code Mfr Part Number 80009 672 1068 00 80009 670 1706 02 80009 253 1105 01 80009 670 7667 00 80009 670 7666 00 80009 670 7666 02 80009 670 7666 01 80009 670 7666 03 80009 672 1068 00 80008 670 1706 02 74970 273 0001 101 01121 881055 75042 CERTO 1004D 80009 263 1105 01 80009 105 0242 02 80009 105 0241 01 80009 105 0242 02 80009 105 0241 01 45 ee E o PA am zu zu Component No 1 3 621 621 630 ATA3CR631 1 634 1 635 A1A3CR638 A1A3CR639 641 A1A3CR647 A1A3CR648 A1A3Q620 A1A3R620 A1A3R621 1 38622 629 630 8631 1 38633 A1A3R634 A1A3R635 A1A3R637 14030638 A1A3R639 1 38640 A1A3R641 1 38642 ATASR643 10301645 1 38646 A1A3R647 A1A3R648 A1ASR660 A1A3R660 18630661 1 38663 1 38665 1 38666 A1A3R668 A1A3R670 ATA3R672 ATASR675 A1A3R676 1 677 1 38679 81 1 35667 1 38667 A1A3U675 Tektronix Part No 870 7667 00 283 0177 00 152 0141 02 152 0141 02 152 0141 02 152 0141 02 152 0141 02 152 0141 02 152 0141 02 152
19. Section 8 7A18A DIAGRAMS AND CIRCUIT BOARD ILLUSTRATIONS Symbols Graphic symbols and class designation letters are based on ANSI Standard Y32 2 1975 Logic symbology is based ANSI Y32 14 1973 in terms of positive logic Logic symbols depict the logic function performed and may differ from the manufac turer s data The overline on a signal name indicates that the signal performs its intended function when it is in the low state Abbreviations are based on ANSI Y1 1 1972 Other ANSI standards that are used in the preparation of diagrams by Tektronix Inc are Assembly Numbers and Grid Coordinates Each assembiy in the instrument is assigned an assembly number e g A20 The assembly number appears on the circuit board outline on the diagram in the title for the circuit board component location illustration and in the lookup table for the schematic diagram and corresponding component locator illustration The Replaceable Electrical Parts listisarranged by assemblies in numerical sequence the components are listed by component number see following illustration for constructing a component number Function Block Title internal Screwdriver a Adjustment Cam Switch Closure Chart Dot indicates switch closure Etched Circuit Board Outlined in Black Refer to Wavetorm _2 p ik ER Function Block Outline TS 514 EM type m
20. 24115 te f ZY ai IVIV JIdAVXS 918MVIM ININOAWOS uonoeg 985 821A9Q 1 1 19 211215 dor THAI 4 MI 195 THD OL OL H Amar 110212 INOS THO ovr E LAOS LIOA 54 4575 LS 25214980 189 95 092909 IVIV 4944 4790 Vi oo 6 CI pa ON i I I I 4407 DILO VITA OL i I 1 I l i95 i i I I I 1 i i i 1 e O O Q ai o al O O o O 1 a p ps 5 er i I p a 1 oL 9 MT 1 5 E Al E 035336 58 y Aider voozs Manon 5 Gvile 19 os 5 os a a g a g 5 a e aaron SUONANO Y SAAVAN 100 731408 OPTION 6 CHANNEL 1 INPUT AMPLIFIER P O A2 ASSY Option 6 CH 1 Input Ampl C210 C212 C216 C225
21. 50 pF and 47 k 100k Q selected for optimum risetime and minimum aberrations 0 50 pF and 47 k 100k9Q Component C246 CH 1 Input to 2nd R246 Cascode Amplifier C545 CH 2 input to 2nd R545 Cascode Amplifier 5 6 REV JUN 1983 SCL O AIDA OPTION INFORMATION Your instrument may be equipped with one or more op tions This section describes those options or directs the reader to where the option is documented Option 06 DC OFFSET Described in this section The 7A18A with Option 06 is equipped with added DC offset cirucits that provide up to 200 divisions of baseline offset within the input dynamic range with uncalibrated front panel variable controls for each channel DC OFFSET The internal DC Balance circuits have been modified to provide up to 1 V DC offset directly to the input of each amplifier which gives up to 200 divisions of baseline offset range for all VOLTS DIV settings CONTROLS Separate CH 1 CH 2 uncalibrated Variable Offset controls are added to the front panel Each input coupling selector switch has an additional position for the DC offset function The variable controls are concentric with the position controls replacing the IDENTIFY pushbuttons formerly used on the unmodified unit APPLICATION The added Offset facility should be used only for offsetting a DC level in the waveform to be ob served Amplifier characteristics are not sui
22. 513 013A 2 0 10 52911 MA101C102KAA MA101C102KAA 8035BC0G330 MA101C102KAA MATOTASREDAA 513 013A 2 0 10 GC101A101K MA101C102KAA ECE A25V22L 114 681 1 5 MA101C102KAA MA201C103KAA MA101C102KAA 8035BC0G330 MA101C102KAA MATOTASREDAA 513 013A 2 0 10 GC101A101K MA201C103KAA MA201C103KAA MA201C103KAA MA201C103KAA MA201C103KAA MA201C103KAA MA201C103KAA MA201C103KAA 2DDH61L502P 7001 COK 1R8B 7001 COK1R5C ECE A25V22L C114K681K1X5CA MA101C102KAA MA101C102KAA MA101C102KAA 513 013A 2 0 10 MA201C103KAA 101 102 101 102 Replaceable Electrical Parts 7A18A Tektronix Serial Model No Mfr Component Dscont Name amp Description Code Mir Part Number A2C464 281 0819 00 CAP FXD CER 5 50 72982 80358006330 A2C470 281 0812 00 Di 1000PE 10 100V 04222 MA101C102KAA 2 474 281 0810 00 CAP FXD CER 01 5 6 0 5 100 04222 MA101A5R6DAA A2C478 281 0814 00 CAP FXD CER DI 100PF 10 100V 04222 GC101A101K A2C513 281 0812 00 CAP FXD CER DI 1000PF 10 100V 04222 MA101C102KAA 5 A2C518 290 0745 00 CAP FXD ELCTLT 22UF 50 10 25V 54473 ECE A25V22L 2 525 281 0820 00 CAP FXD CER DI 680PF 10 50V 05397 C114K681K1X5CA A2C527 281 0812 00 CAP FXD CER 01 1000 1095 100 04222 MA101C102KAA A2C541 281 0812 00 CAP FXD CER 01 1000 1096 100 04222 MA101C102KAA A2C545 281 0811 00
23. 60 millivolts of one kilohertz signal d CHECK CRT display at each CH 2 VOLTS DIV switch position listed in Table 4 3 for square corner and flat 4 10 Calibration 7A18A top within 0 06 division Re adjust the generator output at each switch position to provide six divisions of deflection ADJUST CH 2 attenuator compensations as given in Table 4 3 for optimum square corner flat top on the displayed waveform use tuning tool Re adjust the genera tor output at each switch position to provide six divisions of deflection See Fig 4 1 for adjustment location f Disconnect the normalizer from CH 2 and connect the signal to the CH 1 input connector 9 Set the DISPLAY MODE switch to CH 1 display at each 1 VOLTS DIV switch position listed in Table 4 3 for square corner and flat top within 0 06 division Re adjust the generator output at each switch position to provide six divisions of deflection i ADJUST CH 1 attenuator compensations as given in Table 4 3 for optimum square corner and flat top on the displayed waveform Re adjust the generator output at each Switch position to provide six divisions of deflection See Fig 4 1 for adjustment location j Disconnect ail test equipment Table 4 3 Attenuator Compensation VOLTS DIV Switch Setting Adjust for Optimum Square Corner Fiat Top Replace in line 50 ohm BNC termination with BNC to BNC male adapter
24. Set the CH2 VARIABLE control to the CAL IN position Fig 4 1 Locations of adjustments used this procedure 2 Adjust Channel 1 and 2 GAIN a Connect the standard amplitude calibrator to the CH 2 input connector with the 42 inch cable b Set the standard amplitude calibrator for 50 millivolt square wave output c Position the display to the center of the graticule with the CH 2 POSITION control d CHECK CRT display for exactly five divisions in amplitude e ADJUST CH 2 GAIN adjustment front panel for exacity five divisions of deflection To adjust press in the GAIN knob with a screwdriver and turn until the GAIN con trol is engaged 1 Disconnect the standard amplitude calibrator from the CH 2 input connector and connect it to the CH 1 input connector g Set the DISPLAY MODE switch to CH 1 REV JUN 1983 h Position the display to the center of the graticule with the CH 1 POSITION control i display for exactly five divisions in amplitude j ADJUST CH 1 GAIN adjustment front part for ex actly five divisions of deflection k Disconnect all test equipment 3 Adjust Channel 1 and 2 Input Capacitance a Remove the 7A18A from the Indicator Oscilloscope Place the 7A18A on the plug in extender and plug the ex tender into the left vertical compartment b Set the CH 1 and CH 2 VOLTS DIV switches to 5 mV c Connect t
25. diodes and FET s used in this instrument is helpful A transistor curve tracer such as the Tektronix Type 576 will give the most complete information 2 DC Voltmeter and Ohmmeter A voltmeter for check ing voltages within the circuit and an ohmmeter for checking resistors and diodes are required Plastic Case Transistors NOTE 3 Test Oscilloscope A test oscilloscope is required to view waveforms at different points in the circuit Tektronix 7000 Series Oscilloscope equipped with a readout system 7D13A Digital Multimeter unit 7B Series Time Base Unit and a 7A Series Amplifier Unit with a 10X probe will meet the needs for items 2 and 3 Troubleshooting Procedure This troubleshooting procedure is arranged in an order which checks the simple trouble possibilities before pro ceeding with extensive troubleshooting 1 Check Control Setting An incorrect setting of the 7A18A controls can indicate a trouble that does not exist If there is any question about the correct function or operation of a control or front panel connector see the Operating In structions section 2 Check Associated Equipment Before proceeding with troubleshooting of the 7A18A check that the equipment case LEAD CONFIGURATIONS AND CASE STYLES ARE TYPICAL BUT MAY VARY DUE TO VENDOR CHANGES OR INSTRUMENT MODIFICATIONS cathode Dual Diode Dual FET integrated Circuit 1126 124 Fig 5 1 Electrode configuration for semicond
26. emitter resistor R622 the collector current When the 15 volt time slot pulse is applied to Interface Connector B33 0620 is interrogated and its collector current is added to the column current output through Interface Connector A37 With a 1X probe or no probe connected to the input connector Q620 is turned off The deflection factor readout is determined by the VOLTS DIV switch position With a 10X probe connected the bias on Q620 will allow 100 microamperes of collector current to flow This increases the deflection factor readout by a factor of 10 The IDENTIFY button 813 or S23 on Diagram 1 does two things when pressed 1 It causes the trace representing the appropriate chan nel of the 7A18A to move about 0 3 division see the discus sion on the Channel 1 or Channel 2 Input Amplifier 2 Forward biases CR621 0620 to result in a suffi cient amount of collector current which when added to the column current output replaces the deflection factor read out with the word IDENTIFY These two actions aid in identifying the 7A18A trace when multiple traces are displayed When the IDENTIFTY button is released the deflection factor readout and trace position are restored For further information on the operation of the readout system see the oscilloscope instruction manual Section 4 7 18 PERFORMANCE CHECK AND ADJUSTMENT Recalibration Interval To assure instrument accuracy check the cal
27. these switches is defective the entire switch assembly should be replaced A new switch can be ordered through your Tektronix Field Office When disconnecting or connecting leads to a wafer type rotary switch do not let solder flow around and beyond the rivet on the switch terminal Excessive sol der can destroy the spring tension of the contact Transistor and Integrated Circuit Replacement Transistors and IC s should not be replaced unless they are actually defective If removed from their sockets during routine maintenance return them to their original sockets Special care must be given to integrated circuit leads be Maintenance 74A18A cause they can easily be damaged in removal from sockets Unnecessary replacement or switching of components may affect the calibration of the instrument When a transistor is replaced check the operation of that part of the instrument that may be affected Recalibration After Repair After any electrical component has been replaced the calibration of that particular circuit should be checked as weli as the calibration of other closely related circuits The Performance Check instructions given in Part of Section 4 provide a quick and convenient means of checking the in strument operation The Calibration Procedure in Part Il of Section 4 can then be used to adjust the operation to meet the Performance Requirements listed in Section 1 Repackaging for Shipment the Tektronix i
28. 0 0263 1N4152 263 1N4152 263 1N4152 NDP0263 1N4152 263 1N4152 NDP0263 1N4152 263 1N4152 X16P4039 NTR25J E470E MFF1816G20000F MFF1816G12701F NTR25J E 100 NTR25J E150K NTR25J E75K0 NTR25J E75K0 NTR25J E150K MFF1816G37401F NTR25J E150K NTR25J E150K NTR25J E75K0 NTR25J E7SKO NTR25J E150K NTR25J E51KO MFF1816G37401F NTR25J E150K NTR25J E150K NTR25J E 13K NTR25J E150K CMF55116G75R00F MFF1816G54R90F MFF1816G165RO0F 18M838 CMF55116G13000F CMF55116G69R80F 14M403 MFF1816G45300F NTR25J E100K MFF1816G19100F CHB14FXE52 30HM CRB14FXE52 30HM NTR25J E24K0 MFF1816G45300F 131 0604 00 MC1458JG4 REV MAR 1985 Component A2C210 A2C212 A2C212 A2C216 A2C225 A2C241 2 245 2 246 2 246 A2C256 A2C257 2 264 A2C270 A2C274 A2C275 A20278 A2C313 22 A2C318 26325 _ 2 341 A2C345 2 356 A2C364 A2C370 A2C374 A2C375 A2C378 A2C391 A2C392 A2C393 A2C394 A2C395 A2C396 A2C397 A2C398 A2C410 A2C412 A2C412 2 416 2 425 A20427 A20429 A2C441 2 445 2 446 2 456 A2C457 MAR 1985 Tektronix Part No 670 7666 00 670 7666 02 670 7666 01 670 7666 03 283 0001 00 281 0557 00 281 0529 00 290 0745 00 281 0820 00 281 0812 00 281 0221 00 281 0811 00 281 0812 00 281 0812 00 281 0819 00 281 0812 00 281 0810 00 281 0221 00 281 0814 00 281 081
29. 4 Set the VOLTS DIV switch to display about five divi sions of the waveform vertically 5 Set the time base Triggering controls for a stable dis play Set the time base unit to a sweep rate which displays several cycies of the waveform 6 Turn the 7A18A POSITION control so the lower por tion of the waveform coincides with one of the graticule lines below the center horizontal line and the top of the wave form is within the viewing area With the time base Position controi move the display so one of the upper peaks lies near the center vertical line see Fig 2 2 7 Measure the divisions of vertical deflection peak to 1 peak Check that the VARIABLE VOLTS DIV control is in gt the CAL IN position NOTE This technique can also be used to make measure ments between two points on the waveform rather than peak to peak Centerline em A WB Position To _ i 4 cpm 4 HM E Au 1 Vertical E Fig 2 2 Measuring the peak to peak voltage of a waveform 8 Multiply the deflection measured in step 7 by the 7 VOLTS DIV switch setting include the attenuation factor of the probe if used EXAMPLE Assume that the peak to peak vertical de flection is 4 5 divisions see Fig 2 2 using a 10X attenuator probe and the VOLTS DIV switch is set to 1 V vertical Volts ertical vOLTS DIV prone deflection X X attenuation Peak
30. 7A18A can be operated in any plug in compart ment of the 7000 Series Oscilloscopes The following electrical characteristics are valid over the stated environmental range for instruments calibrated at an ambient temperature of 20 C to 30 and after a five minute warmup unless otherwise noted Table 1 1 ELECTRICAL Characteristic Deflection Factor Calibrated Range 1 2 5 sequence Deflection Factor Accuracy 10 mV Div Uncalibrated VARIABLE Performance Requirement 5 mV Div to 5 V Div ten steps in a Supplemental Information Within 296 with GAIN adjusted at Continuously variable between calibrated steps extends deflection factor to at least 12 5 V Div GAIN Frequency Response System Dependent 8 div reference signal Upper Bandwidth DC Direct 75 MHz Lower Coupled With 10X Probe 10 Hertz or less 1 Hertz or less Maximum Input Voltage DC Coupled Permits adjustment of deflection factor for calibrated operation with all 7000 series oscilloscopes 250 volts DC Peak AC AC component 500 volts peak to peak maximum one kilohertz or less AC Coupled 500 volts DC Peak AC AC component 500 volts peak to peak _ hannel Isolation maximum one kilohertz or less 50 1 display ratio up to 50 megahertz Specification 7A18A Table 1 1 cont __ ______ Characteristics Performance Requiremen
31. C241 C245 C246 C256 C257 C264 C313 C318 C325 C345 C356 C364 CR210 CR220 CR221 CR256 05220 05221 Q210A 02108 Q225 0240 0245 0250 0260 P O A2 ASSY also shown on P O A1A3 ASSY Option 6 CH 1 Input Ampl P O A1A3 ASSY also shown on OPTION 06 CHANNEL 1 INPUT AMPLIFIER e f oaoa TN 425 LOdNI I HO 90 0430 91 1 TWNDIS N 91491 Viva 940 de rer OLY sn sueg alqeaceiay je pua 245 e 190 260 OU sjuauodsioo pajun O Sissego 5 9595 abii Sy 40999 295 sAnisueg DIJLIS Boni MHG CUT fiquuassy onewegg ar t y tere VETTY CV 574 et _ Ase 39V0M 1N3NOdWOO amp AGA 7 be i 3 ND 21 vy DATE ty 3395141 Af T HO 4 TX vs 41 49 PLOY MEA on 7 i 0 ait 2 bey 30 oap db 8155 426802 8592 IX Lie gt 100 9512 3 3 Sl Ls gt ANNIS T idas Luce 57 Su MLS 1199 OL L o 8 salz Re tase 119 47 OL 3194 OL
32. CAP FXD CER DI 10PF 1095 100V 96733 R2911 A2C545 NOMINAL VALUE SELECTED 0 50PF A2C556 281 0812 00 CAP 01 1000 10 100 04222 101 102 A2C564 281 0819 00 CAP FXD CER Di 33PF 5 50V 72982 8035BC0G330 A2C570 281 0812 00 CAP FXD CER Di 1000PF 1096 100V 04222 101 102 A2C574 281 0810 00 DI 5 6PF 0 5 100V 04222 MA101A5R6DAA A2C578 281 0814 00 CAP FXD CER DI 100PF 10 100V 04222 GC101A101K bes A2C584 281 0812 00 01 1000 1096 100 04222 101 102 A2C591 281 0773 00 CER D1 0 1UF 20 50V 04222 MA201C103KAA A2C592 281 0773 00 CAP FXD CER D1 0 1UF 20 50V 04222 MA201C103KAA A2C593 281 0773 00 FXD CER Df 0 1UF 2096 50V 04222 MA201C103KAA A2C594 281 0773 00 CAP EXD CER Di 0 1UF 20 50V 04222 MA201C103KAA A2C595 281 0773 00 CAP FXD CER Dt 0 1UF 20 50V 04222 MA201C103KAA A2C596 281 0773 00 CAP FXD CER DI 0 1UF 20 50V 04222 MA201C103KAA A2CR210 152 0321 00 SEMICOND DEVICE SILICON 30V 0 1A 07263 FSA1480 A2CR220 152 0141 02 SEMICOND DVC DHSW S1 30V 150MA 30V DO 35 12969 263 1N4152 A2CR221 152 0141 02 SEMICOND DVC DESW SI 30V 150MA 30V DO 35 12969 NDP0263 1N4152 A2CR256 152 0141 02 SEMICOND DVC DESW S1 30V 150MA 30V DO 35 12969 NDP0263 184152 A2CR410 152 0321 00 SEMICOND DEVICE SILICON 30V 0 1A 07263 FSA1480 A2CR420 152 0141 02 SEMICOND DVC DI SW St 30V 150MA 30V DO 35 12969 263 1N4152 A2CR421 152 0
33. Model No E Mfr Tektronix Component No Part No Dscont Name amp Description Code Mir Part Number A2R263 315 0272 00 RES FXD CMPSN 2 7K OHM 596 0 25W 57668 NTR25J E02K7 A2R264 315 0330 00 RES FXD CMPSN 33 OHM 5 0 25W 57668 NTR25J E A2R274 315 0242 00 RES 2 4 0HM 5 0 25W 57668 NTR25J E02K4 A2R275 315 0100 00 RES FXD CMPSN 10 OHM 5 0 25W 57668 NTR25J E 1060 A2R276 321 0059 00 RES FXD FILM 49 2 OHM 1 0 125W 91637 CMF55116G50R20F A2R277 321 0059 00 HES FXD FILM 40 2 OHM 195 0 125W 91637 CMF55116G50R20F A2R278 323 0189 00 RES FXD FILM 909 OHM 1 0 50W 24546 NA65 9090F 28280 315 0330 00 RES FXD CMPSN 33 OHM 596 0 25W 57668 NTR25J E 33E A2R282 323 0150 00 RES FXD FILM 357 OHM 1 0 50W 91637 MFF1226G357RO0F A2R286 323 0206 00 RES FXD FILM 1 37K OHM 1 0 50W 75042 CECTO 1371F 28313 315 0105 00 RES FXD CMPSN 1M OHM 595 0 25W 57668 NTR255 E 1M A2R317 321 0032 00 RES FXD FILM 21 OHM 1 0 125W 91637 MFF1816G21 ROOF A2R318 315 0911 00 RES FXD CMPSN 910 OHM 595 0 25W 57668 NTR25J E910E A2R319 315 0391 00 RES FXD CMPSN 390 OHM 5 0 25W 57668 NTR25J E390E A2R320 315 0152 00 RES FXD CMPSN 1 5K OHM 5 0 25W 57668 25 01 5 Po A2R321 311 0633 00 RES VAR NONWIR 5K OHM 10 0 50W 73138 82PR5K 30C A2R322 315 0133 00 RES FXD CMPSN 13K OHM 5 0 25W 57868 NTR25J E 13K A2R323 315 0131 00 RES FXD CMPSN 130 5 0 25 57668 NTR25J E 130E Ui A2R324 321 0032 00 RES FXD FILM 21 OHM 1 0 125W 916
34. REPLACEABLE ELECTRICAL 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 is therefore impor tant 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 locat Tektronix Inc Field Office or represen tative will contact you concerning any change in part number Change information it any is located at the rear of this manual LIST OF ASSEMBLIES A tist of assemblies can be found at the beginning of the Electrical Parts List The assemblies are listed in numerical order Whenthe complete component number of a partis known this list will identify the assembly in which the part is located CROSS INDEX MFR CODE NUMBER TO MANUFACTURER The Mir Code Number to Manufacturer index for the Electrical Parts List is located immediately after this page The Cross index provides codes names and addresses of manufac turers of components listed in the Electrical Parts List ABBREVIATIONS Abbreviations conform to American National Standard Y 1
35. TUBE PLSTC PLASTIC TERM TERMINAL PN PART NUMBER THD THREAD PNH PAN HEAD THK THICK PWR POWER TNSN TENSION RECEPTACLE TPG TAPPING RES RESISTOR TRH TRUSS HEAD RGD RiGID VOLTAGE RLF RELIEF VAR VARIABLE RTNR RETAINER Wi WITH SCH SOCKET HEAD WSHR WASHER OSCILLOSCOPE XEMA TRANSFORMER SCR SCREW XSTR TRANSISTOR REV FEB 1983 9 1 Replaceable Mechanical Parts 7A18A Mfr Code 000BK 000CV 000FW 00779 01121 08922 12327 22526 22599 24931 70278 71590 72228 73743 77900 78189 79136 80009 83385 85928 87308 92101 93907 97464 10435 T0588 CROSS INDEX MFR CODE NUMBER TO MANUFACTURER Manufacturer STAUFFER SUPPLY NORTHWEST FASTENER SALES INC WESTERN SINTERING CO AMP INC ALLEN BRADLEY COMPANY BURNDY CORPORATION FREEWAY CORPORATION BERG ELECTRONICS INC ESNA DIV OF AMERACE CORPORATION SPECIALITY CONNECTOR CO INC ALLIED STEEL AND CONVEYORS DIV OF SPARTON CORP CENTRALAB ELECTRONICS DIV OF GLOBE UNION INC CONTINENTAL SCREW CO DIV OF AMTEL INC FISCHER SPECIAL MFG CO SHAKEPROOF DIV OF ILLINOIS TOOL WORKS ILLINOIS TOOL WORKS INC SHAKEPROOF DIVISION WALDES INC TEKTRONIX INC CENTRAL SCREW CO SEASTROM MFG COMPANY INC L INDUSTRIES INC SOUTHERN SCREW DIV SCHULZE MFG 50 INGOLD RD BURLINGAME CA 94010 TEXTRON DIV INDUSTRIAL RETAINING RING CO LEWIS SCREW CO UNI
36. control knob and turning the knob with narrow blade screwdriver see Front Panel Controls and Connectors Turn the knob clockwise then counterclock wise until the GAIN control is engaged When the GAIN control is engaged the vertical deflection will change as the knob is turned Turn the GAIN control knob with the screw 7 driver until the deflection is set to exactly four divisions then remove the screwdriver input Coupling The Channel 1 and Channel 2 coupling AC GND DC switches allow a choice of input coupling methods The type of display desired and the applied signal wili determine the coupling to use The DC coupling position must be used to display the DC component of the signal it must also be used to display AC signals below about 30 Hz ten hertz with a 10X probe and square waves with low frequency components as these sig nals are attenuated in the AC position in the AC coupling position the DC component of the signal is blocked by a capacitor in the input circuit The AC coupling position provides the best display of signals with a DC component much larger than the AC components The precharge feature should be used with large DC inputs To use this feature first set the coupling to GND Connect the probe to the circuit and wait about two seconds for the cou pling capacitor to charge Then set the coupling to AC The GND position provides a g
37. exact number of divisions of deflection The adjustment will be easier and more accurate if arbitrary units of measurement are established so that the correct adjust ment is indicated by an exact number of divisions of deflec tion The following procedure describes how to establish arbitrary units of measure for comparison measurements establish an arbitrary vertical deflection factor based upon a specific reference amplitude proceed as follows 1 Connect the reference signal to the input connector Set the time base unit sweep rate to display several cycles of the signal 2 Set the VOLTS DIV switch and the VARIABLE con trol to produce a display which is an exact number of verti cal divisions in amplitude Do not change the VARIABLE control after obtaining the desired deflection 3 To establish an arbitrary vertical deflection factor so the ampiitude of an unknown signal can be measured accu rately at any setting of the VOLTS DIV switch the ampli tude of the reference signal must be known If it is not known it can be measured before the VARIABLE VOLTS DIV control is set in step 2 4 Divide the amplitude of ithe reference signal volts by the product of the vertical deflection divisions established in step 2 and the setting of the VOLTS DIV switch This is the vertical conversion factor Vertical reference signal Conversion ampliltude volts Factor vertical VOLTS DIV deflection X Switch divisions se
38. of Q450 Q550 This results in a fixed zero volts approximately dif ference between the collectors Since 50 volts is not applied to the POSITION control in the ADD position of the DISPLAY MODE switch the control setting has no effect on the circuit operation 3 4 CHANNEL SWITCHES General The Channel Switches circuit provides Signal and Trigger outputs to the oscilloscope via the Interface Connector as determined by the DISPLAY MODE and TRIGGER SOURCE switches A schematic of this circuit is given on Diagram 4 in the Diagrams section Signal Channel Switch The Signal Channel Switch stage consists of integrated circuit U270 and its external components This stage selects one or mixes two input analog signals in response to inputs from the DISPLAY MODE switch The Signal Channel Switch stage determines which input CH 1 or CH 2 pro vides the signal to the oscilloscope as controlled by the DIS PLAY MODE switch setting Resistors R276 R277 and R376 R377 set the current gain for each channel Networks C274 R274 C275 R275 and C374 R374 C375 R375 pro vide high frequency compensation for each channel C275 and C375 in these networks are high frequency compensa tion adjustments Figure 3 3 shows the U270 input combinations for each position of the DISPLAY MODE switch When the level at pin 14 is LO the output of U270 is determined by the level at pin 4 With the level at pin 14 HI and the level at pin 4 LO pec
39. outside of the board 2 Remove the seven screws holding the board to th mounting surface 3 Disconnect the wires connected to the inside of the board 4 Remove the board from the unit 5 I0 the board reverse the order of removal ATTENUATOR CIRCUIT BOARD REMOVAL 1 Remove the readout board as outlined in the previous procedure 2 Disconnect the resistor capacitor connected to the rear of the board 3 Loosen the front set screw on the VARIABLE GAIN control shaft coupling use a 0 050 inch hex key wrench 4 Remove the red VARIABLE control knob and from the control shaft 5 Remove the remaining front panel knobs using M16 inch hex key wrench 6 Remove the front panel from the instrument 7 Remove the attenuator shields 8 Disconnect the wires and resistor from the input connector 9 Remove the input BNC connector 10 Remove the POSITION control using a 5 16 inch nut driver 11 Remove the attenuator board with cam switch from _ the instrument 12 To replace the board reverse the order of removal AMPLIFIER CIRCUIT BOARD REMOVAL 1 Remove the Readout circuit boards as given previously 2 Remove the plastic plug in guide from the rear of the instrument 3 Disconnect the wires connected to the board from the front panel controls 4 Loosen the front hex socket screw in the front cou pling of the VARIABLE control shaft using a 0 0
40. po sitioning The outputs of these circuits are applied push pull to the Signal and Trigger Channel Switches The Channel Switches select the proper signal and trig ger as determined by the DISPLAY MODE and TRIGGER SOURCE switches The signal and trigger outputs are pro vided to the oscilloscope via the Interface Connector The Readout Encoding circuit provides readout logic for the oscilloscope readout system Data is supplied to the mainframe readout system identifying the polarity deflection factor the uncalibrated symbol when the VARIABLE con troi is in the outward position and the plug in mode When the IDENTIFY button is pressed the trace is deflected about 0 3 division and the deflection factor readout is replaced by the word IDENTIFY DETAILED CIRCUIT DESCRIPTION ATTENUATOR General The Attenuator circuit determines the input coupling and the 7A18A deflection factor NOTE The CH 1 and CH 2 Attenuator circuits are identical To minimize duplication only CH 1 is described in de tail throughout this discussion AC GND DC Switch Input signals connected to the input connector can be ac coupled dc coupled or internally disconnected S100A is a cam type switch a contact closure chart showing the oper ation is given on Diagram 1 The dots on this chart indicate when the associated contacts are in the position shown open or closed When the AC GND DC switch is in the DC position the input signal i
41. 0 L RIBBON 80009 175 7209 00 130 352 0169 02 2 HLOR TERM CONN 2 WIRE RED 80009 352 0169 00 131 175 7210 00 1 CA ASSY SP ELEC 3 26 AWG 8 0 L 80009 175 7210 00 132 352 0161 09 1 CONN BODY PL EL 3 WIRE WHITE 80008 352 0161 09 133 175 7211 00 1 CA ASSY SP ELEC 4 26 AWG 2 0 L RIBBON 80009 175 7211 00 134 352 0162 07 1 HLDR TERM CONN 4 WIRE VIOLET 80009 352 0162 07 135 175 2774 00 1 CA ASSY SP ELEC 5 26 AWG 3 0L 80009 175 2774 00 352 0163 05 2 HLDR TERM 5 WIRE GREEN 80008 352 0163 05 9 5 Replaceable Mechanical Parts 7A18A Fig amp index 1 137 138 139 140 141 142 143 144 145 Tektronix Part No 175 7212 00 352 0163 05 175 7213 00 352 0163 03 175 2582 00 352 0164 00 175 8012 00 131 0707 00 352 0163 00 352 0164 03 Serial Model No Eff Dscont Qty non 12345 amp Description ASSY SP ELEC 5 26 AWG 4 0 L HLDR TERM CONN 5 WIRE GREEN ASSY SP ELEC 5 26 AWG 3 0 L RIBBON HLDR TERM CONN 5 WIRE ORANGE ASSY SP ELEC 6 26 AWG 3 0 L RIBBON HLDR TERM 6 WIRE BLACK CA ASSY SP ELEC 9 26 AWG 5 5 L RIBBON CONTACT ELEC 22 26 AWG BRS 8 CU BE GOLD HLDR TERM CONN 5 WIRE BLACK HLDR TERM CONN 6 WIRE ORANGE Mfr Code 80009 80009 80009 80009 80009 80009 80009 22526 80009 80009 Mir Part Number 175 7212 00 352 0163 05 175 7213 00 352 0163 03 175 2582 00 352 0164 00 175 8012 00 47439 352 01
42. 00 A 333 1411 01 1 PANEL FRONT 80009 333 1411 01 18 348 0235 00 2 SHLD GSKT ELEC 4 734 INCH LONG 92101 ORD BY DESCR 519 358 0216 00 1 BUSHING PLASTIC 0 257 ID X 0 412 INCH OD 80009 358 0216 00 1 20 131 1075 00 1 CONTACT ELEC GROUNDING CU HEAT TRTD 80009 131 1075 00 _ 21 1 SWITCH SLIDE SEE 22 REPL ree HH ATTACHING PARTS 22 210 0405 00 2 NUT PLAIN HEX 2 56 X 0 188 BRS CD PL 73743 12157 50 23 210 0259 00 2 TERMINAL LUG 0 099 D LOCKING BRS CD PL 80009 219 0259 00 24 211 0030 00 2 5 2 56 X 0 25 FLH 82DEG STL 83385 ORD BY DESCR inveni c END ATTACHING PARTS J et 25 2 RESISTOR VAR SEE R11 R21 REPL tee ATTACHING PARTS 26 210 0583 00 2 NUT PLAIN HEX 0 25 32 X 0 312 INCH BRS 73743 2X20317 402 enne END ATTACHING PARTS 27 210 0223 01 2 TERMINAL LUG 0 25 INCH DIA SE 60 DEG BEN 86928 ORD BY DESCR 28 386 1447 54 1 SUBPANEL FRONT 80009 386 1447 54 emm ATTACHING PARTS 29 213 0793 00 4 SCREW TPG TF 6 32 X 0 4375 TAPTITE FIL 93907 ORD BY DESCR END ATTACHING PARTS 30 214 1054 00 1 SPRING FLAT 0 825 X 0 322 857 80009 214 1054 00 31 105 0075 00 1 BOLT LATCH 7A 4 7B SER PL IN 80009 105 0075 00 32 210 0288 00 2 TERMINAL EUG 0 125 ID X 1 125 INCH LONG 80009 210 0288 00 een ATTACHING enee 33 210 0586 00 2 NUT PL ASSEM WA 4 40 X 0 25 5TL CD PL T0435 ORD BY DESCR 34 211 0105 00 2 SCREW MACHINE 4 40 X 0 188 100 DEG FLH ST 83385 BY DESCR fenem ND ATTACHING
43. 0009 153 0597 00 20245 153 0582 00 SEMICOND DVC SE SILICON FET PAIR 22229 52114 20250 153 0597 00 SEMICOND SE SILICON PNP 80009 153 0597 00 7 6 1985 Component 20260 A20280 A20320 20325 A2Q340 A2Q345 A2Q350 A2Q360 20380 A20410 A20420 A20425 A2Q426 A2Q440 A2Q445 A2Q450 A20460 A2Q480 A2Q520 A20525 A20526 A2Q540 A2Q545 A2Q550 A2Q560 27 20580 98210 28211 A2R212 A2R215 A2R216 A2R218 A2R222 28223 28224 A2R225 A2R226 A2R227 A2R236 A2R240 A2R241 A2R242 A2R243 A2R244 A2R245 A2R246 A2R246 A2R248 A2R250 A2R251 A2R256 A2R257 A2R259 A2R260 REV MAR 1985 Tektronix Part No 151 0441 00 151 0221 00 153 0631 00 151 0225 00 153 0597 00 153 0582 00 153 0597 00 151 0441 00 151 0221 00 151 1032 00 153 0631 00 153 0595 00 153 0595 00 153 0597 00 153 0582 00 153 0597 00 151 0441 00 151 0221 00 153 0631 00 153 0595 00 153 0595 00 153 0597 00 153 0582 00 153 0597 00 151 0441 00 151 0221 00 316 0474 00 315 0470 00 315 0561 00 315 0391 00 315 0911 00 321 0032 00 321 0153 00 323 0257 00 321 0032 00 315 0621 00 321 0122 00 315 0561 00 315 0242 00 321 0356 00 315 0221 00 321 0068 00 323 0255 00 321 0126 00 311 0634 00 315 0912 00 315 0203 00 321 0105 00 321 0137 00 315 0471 00 315 0153 00 315 0103 00_ 315 0101 00 Serial Modei No Eff Dscont Replaceable Electri
44. 0141 02 152 0141 02 152 0141 02 151 0281 00 315 0471 00 321 0222 00 321 0299 00 315 0101 00 315 0154 00 315 0753 00 315 0753 00 315 0154 00 321 0344 00 315 0154 00 315 0154 00 315 0753 00 315 0753 00 315 0154 00 315 0513 00 321 0344 00 315 0154 00 315 0154 00 315 0133 00 315 0154 00 321 0085 00 321 0072 00 321 0118 00 311 1853 00 321 0108 00 321 0082 00 311 1854 00 321 0256 00 315 0104 00 321 0220 00 321 0070 00 321 0070 00 315 0243 00 321 0256 00 131 0604 00 156 0158 07 OFO 3 Serial Model No Dscont B010100 8011649 B011650 Ranlaraahin Flortrical Parte 7 AIRA Name amp Description CKT BOARD ASSY READOUT DI 1UF 80 20 25V DVO DI SW S 30V 150MA 30V DO 35 SEMICOND DVC DI S8W 1 30V 150MA 30V DO 35 SEMICOND DVC DI SW SI 30V 150MA 30V DO 35 SEMICOND DVC DI SW S1 30V 150MA 30V DO 35 SEMICOND DVOC DI SW S1 30V 150MA 30V DO 35 SEMICOND DVC DI SW S1 30V 150MA 30V DO 38 SEMICOND DVC DI SW S1 30V 150MA 30V DO 35 SEMICOND DVC DI SW SI 30V 150MA 30V DO 35 SEMICOND DVC DESW S1 30V 150MA 30V DO 35 SEMICOND DVC Dt SW Si 30V 150MA 30V D0 35 TRANSISTOR SILICON NPN RES FXD CMPSN 470 OHM 5 0 25W RES FXD FILM 2K OHM 1 0 125W RES FXD FILM 12 7K OHM 195 0 125W RES FXD CMPSN 100 5 0 25 RES FXD CMPSN 150K OHM 5 0 25W RES FXD CMPSN 75K OHM 5 0 25W RES FXD CMPSN 75K 0HM 5 0 25W RES FXD CMPSN 150K 5 0 25 RES FXD FHLM
45. 09 80009 00779 00773 80009 80009 78189 80009 80009 70278 Part Number ORD BY DESCR 214 0579 00 124 0162 00 355 0046 00 DILB16P 108T 200 0945 01 ORD BY DESCR 200 0945 00 75060 012 48283 036 407 0912 00 214 1061 00 129 0554 01 ORD DESCR ORD BY DESCR 2X28269 402 1220 02 00 0541C 175 3093 00 352 0169 00 175 6178 00 352 0169 05 175 6998 00 352 0163 00 175 5414 00 352 0165 09 441 0992 04 BY DESCR 1204 00 000541C 129 0299 00 1204 00 000541C 12157 50 ORD BY DESCR ORD BY DESCR ORD BY DESCR 131 1031 00 131 1030 00 1 332095 2 1 331677 4 210 3082 00 337 1406 00 51 040445 01 131 0907 00 105 0243 00 DESCR REV 1985 E Fig amp 107 5 136 REV MAR 1985 Replaceable Mechanical Parts 7A18A index Tektronix Serial Model No Mir No Part No Dscont Qty 12345 Name amp Description Code Part Number 1 90 401 0180 00 2 SW FRONT 4 REAR 80009 401 0180 00 s ATTACHING PARTS nte 91 354 0390 00 2 RING RETAINING 0 338 ID X 0 025 THK STL 79136 5100 37MD END ATTACHING PARTSy mmm da 92 210 0406 00 24 NUT PLAIN HEX 4 40 X 0 188 BRS CD PL 73743 12161 50 93 214 1752 00 8 80009 214 1752 00 94 214 1139 00 2 SPRING FLAT 0 885 X 0 156 CU GLD CLR 80009 214 1139 00 214 1139 02 4 SPRING FLAT GREEN COLORED 80009 214 1139 02 214 1139 03 4 SPRING FLAT RED COLORED 80008 2
46. 1 COMPONENT NUMBER column one of the Electrical Parts List A numbering method has been used to identify assemblies subassemblies and parts Examples of this numbering method and typical expansions are illustrated by the following Example component number ea A23R1234 A23 81234 Assembly number Circuit number Read Resistor 1234 of Assembly 23 Example b component number mag A23A2R 1234 23 A2 R1234 Assembly Subassembty Circuit number number number Read Resistor 1234 of Subassembly 2 of Assembly 23 Only the circuit number wilt appear on the diagrams and circuit board illustrations Each diagram and circuit board iHustration is clearly marked with the assembly number Assembly numbers are also marked on the mechanical exploded views located in the Mechanical Parts List The component number is obtained by adding the assembly number prefixtothe circuit number The Electrical Parts List is divided and arranged by assemblies in numerical sequence e g assembly with its subassemblies and parts precedes assembly A2 with its sub assembiies and parts Chassis mounted parts have no assembly number prefix and are located at the end of the Electrical Parts List TEKTRONIX PART NO column two of the Electrical Parts List indicates part number to be used when ordering replace ment part from Tektronix SERIAL MODEL NO columns three and four of the Electrical Parts List Column three 3 indic
47. 10 0053 00 210 1134 00 131 1031 00 131 1030 00 136 0252 01 136 0333 00 210 3082 00 337 1406 00 211 0292 00 131 0907 00 105 0243 00 213 0214 00 Serial Model No B010100 B011600 Dscont 8011599 Qty AD o o o NS 12345 amp Description CKT BOARD ASSY AMPLIFIER SEE A2 REPL eese ATTACHING SCREW 4 40 X 0 250 PNH STL POZ Ure ATTACHING PARTS CKT BOARD ASSY INCLUDES TERM TEST POINT BRS CD PL TERMINAL BOARD 4 NOTCH CERAMIC STUD MTD MOUNT TERM 0 0 577 INCH SKT PL IN ELEK MICROCKT 16 CONTACT XSTR DUAL TO 18 W 2 56 THD ee ATTACHING PARTS puntos SCREW MACHINE 2 58 X 0 25 INCH PNH STL eter END ATTACHING PARTS COVER HALF XSTR DUAL TO 18 ALUMINUM SOCKET PIN CONN W O DIMPLE TERMINAL PIN 0 365 L X 0 025 PH BRZ GOLD BRACKET CKT BD BRASS CU SN ZN PL SPRING GROUND FLAT SPACER POST 0 975L W 9 094 ID ooo ATTACHING 8 SCREW MACHINE 4 40 X 0 250 PNH STL POZ SCREW TPG TF 4 20 X 0 25 PNH STL CD PE i END ATTACHING PARTS SWITCH ASSY SEE 530 REPL TARO e ATTACHING PARTS 5 NUT PLAIN HEX 0 375 32 X 0 438 BRS WASHER LOCK iNTL 0 384 ID INTL 0 022 TH END ATTACHING PARTS SWITCH ASSY INCLUDES LEAD ASSY ELEC 2 26 AWG 3 0 L RIBBON HLDR TERM CONN 2 WIRE BLACK ASSY SP ELEC 2 26 AWG 4 0 LRIBBON HLDR TERM CONN 2 WIRE GREEN AS
48. 10TH AVE S W WASECA MN 56093 75042 TRW ELECTRONIC COMPONENTS IRC FIXED RESISTORS PHILADELPHIA DIVISION 401 N BROAD ST PHILADELPHIA PA 19108 80009 TEKTRONIX INC P O BOX 500 BEAVERTON OR 97077 82389 SWITCHCRAFT INC 5555 N ELSTON AVE CHICAGO IL 60630 91637 DALE ELECTRONICS INC P O BOX 609 COLUMBUS NE 68601 96733 SAN FERNANDO ELECTRIC MFG CO 1501 FIRST ST SAN FERNANDO CA 91341 7 2 REV MAR 1985 Danlianaahla 784074 Component A1 ATA 2 A1 1 100 102 1 130 1 2 A1A28100 A1A2S200 A1A25300 1 25400 1985 Tektronix Part No 672 1068 00 670 1706 02 263 1105 01 670 7667 00 670 7666 00 670 7666 02 670 7666 01 670 7666 03 672 1068 00 670 1706 02 281 0064 00 317 0105 00 322 0481 01 263 1105 01 105 0242 02 105 0241 01 105 0242 02 105 0241 01 Serial Model No ER Dscont 010100 8011884 011885 010100 8011884 011885 4 Description ASSEMBLIES CKT BOARD ASSY CAM SWITCH AND READOUT BOARD ASSY ATTENUATOR SW CAM ACTR ASSY VOLTS DIV CKT BOARD ASSY READOUT CKT BOARD ASSY AMPLIFIER CKT BOARD ASSY AMPLIFIER CKT BOARD ASSY AMPLIFIER OPTION 06 ONLY CKT BOARD ASSY AMPLIFIER OPTION 06 ONLY CKT BOARD ASSY CAM SWITCH AND READOUT CKT BOARD ASSY ATTENUATOR
49. 14 1139 03 gt _ 2 ACTUATOR SW SEE A1 28100 8300 REPL 96 384 0878 01 2 SHAFT SW FRONT 80009 384 0878 01 97 401 0178 00 2 BEARING CAM SW CENTER 80008 401 0178 00 mH ATTACHING PARTS 98 354 0443 00 2 RING RETAINING 0 328 FREE ID X 0 448 OD 97484 200 37 ATTACHING PARTS 99 2 1425200 5400 REPL 100 384 0880 01 2 SHAFT CAM SW 2 927 i X 0 188 OD INTMD 80009 384 0880 01 101 401 0180 00 2 BEARING CAM SW FRONT amp REAR 80009 401 0180 00 200 1227 01 1 SW 3 8 24 ELEMENTS ALUMINUM 80009 200 1227 01 ree ATTACHING 211 0292 00 6 WSHR 4 40 X 0 29 885 PL 78189 51 040445 01 res END ATTACHING PARTS rer 102 337 1754 00 4 SHIELD ELEC ATTENUATOR 80009 337 1754 00 esse ATTACHING PARTS 103 213 0120 00 12 SCR TPG THD FOR 2 32 X 0 250 INCH PNH STL 83385 DESCR 104 219 0053 00 12 WASHER LOCK 2 SPLIT 0 02THK STL CAD PL ORD BY DESCR 105 210 1110 00 12 WASHER FLAT 0 092 ID X 0 14 OD BRS 86928 ORD BY DESCR rm END ATTACHING PARTS 106 2 CKT BOARD ASSY READOUT SEE A1A3 REPL 131 1031 00 16 CONTACT ASSY EL CAM SWITCH TOP 80009 131 1031 00 108 210 3082 00 16 EYELET METALLIC 0 047 OD X 0 133 L BRASS 80009 210 3082 00 109 131 0608 00 20 TERMINAL PIN 0 365 L X 0 025 BRZ GOLD 22526 48283 036 110 361 0515 00 4 SPACER SWITCH PLASTIC 80009 3
50. 141 02 SEMICOND DVC DI SW SI 30V 150MA 30V DO 35 12969 263 1N4152 A2CR456 152 0141 02 SEMICOND DVC DI SW SI 30V 150MA 30V DO 35 12969 268 1N4152 E A2D8220 150 1000 00 LT EMITTING DIO RED 650NM 40MA MAX 34430 MV 50 A2DS220 OPTION 06 ONLY A2DS221 150 1000 00 LT EMITTING DIO RED 650NM 40MA MAX 34430 MV 50 A2DS221 OPTION 06 ONLY A2DS420 150 1000 00 LT EMITTING DIO RED 650NM 40MA 34430 MV 50 A2DS420 OPTION 06 ONLY A2DS421 150 1000 00 LT EMITTING DIO RED 650NM 40MA 34430 MV 50 A2DS4A21 OPTION 06 ONLY A2LR391 108 0184 00 COIL RF 3 2UH WOUND ON 10 OHM RES 80009 108 0184 00 A2LR393 108 0184 00 COIL RE 3 2UH WOUND ON 10 OHM RES 80009 108 0184 00 A2LR395 108 0184 00 COIL RE 3 2UH WOUND ON A 10 OHM RES 80009 108 0184 00 A2LR396 108 0184 00 COIL RF 3 2UH WOUND ON 19 OHM RES 80009 108 0184 00 A2LR397 108 0184 00 COIL RF 3 2UH WOUND ON 10 OHM RES 80009 108 0184 00 A2LR591 108 0184 00 COIL RF 3 20H WOUND ON A 10 OHM RES 80009 108 0184 00 21 8592 108 0184 00 COIL RF 3 2UH WOUND 10 OHM RES 80009 108 0184 00 A2LR595 108 0184 00 COIL RF 3 2UH WOUND ON A 10 OHM RES 80009 108 0184 00 A2LR596 108 0184 00 COIL RF 3 2UH WOUND 10 OHM RES 80009 108 0184 00 20210 151 1032 00 TRANSISTOR SILICON FET DUAL 17856 DN399 20220 153 0631 00 SEMICOND DVG SE SELECTED 80009 153 0631 00 20225 151 0225 00 TRANSISTOR SILICON NPN 07263 839291 A2Q240 153 0597 00 SEMICOND DVC SE SILICON PNP 8
51. 2 00 290 0745 00 281 0820 00 281 0812 00 281 0773 00 281 0812 00 281 0819 00 281 0812 00 281 0810 00 281 0221 00 281 0814 00 281 0773 00 281 0773 00 281 0773 00 281 0773 00 281 0773 00 281 0773 00 281 0773 00 281 0773 00 288 0001 00 281 0557 00 281 0529 00 290 0745 00 281 0820 00 281 0812 00 281 0812 00 281 0812 00 281 0221 00 281 0773 00 281 0812 00 281 0812 00 Replaceable Electrical 7 1 Serial Model Dscont Name amp Description 010100 8011884 BOARD ASSY AMPLIFIER 8011885 BOARD ASSY AMPLIFIER B010100 8011884 BOARD ASSY AMPLIFIER OPTION 06 ONLY CKT BOARD ASSY AMPLIFIER OPTION 06 ONLY 8011885 CAP FXD CER 01 0 0050 100 0 500 8010100 11884 CAP FXD CER Dl 1 8PF 10 500Y 8011885 01 1 0 25 500V ELCTLT 22UF 50 10 25 CER DI 680PF 10 50V 01 1000 19 100 DI 2 10PF 100V CAP FXD CER DEIOPF 10 100V NOMINAL VALUE SELECTED 0 50PF MAX CAP FXD CER DE 1000PF 1096 100V CAP FXD CER Di 1000PF 10 100V DI 33PF 5 50V CAP FXD CER 01 1000 1090 100 DI 5 6PF 0 5 100V DI 2 10PF 100V CAP DI 100PF 10 100V CAP FXD CER DI 1000PF 10 00V CAP FXD ELCTLT 22UF 50 10 25V CAP FXD CER DI 680PF 1095 50V CAP FXD CER DI 1000PF 10 100V
52. 25 A2R526 A2R527 A2R529 A2R540 A2R541 A2R542 A2R543 A2R544 A2R545 A2R545 A2R549 REV MAR 1985 Tektronix Part No 321 0153 00 323 0257 00 321 0032 00 315 0621 00 321 0122 00 315 0561 00 315 0301 00 315 0561 00 315 0242 00 321 0356 00 315 0221 00 321 0068 00 323 0255 00 321 0126 00 311 0634 00 315 0363 00 315 0203 00 321 0110 00 321 0137 00 315 0272 00 315 0471 00 315 0103 00 315 0101 00 315 0272 00 315 0330 00 315 0182 00 321 0959 00 321 0059 00 323 0189 00 315 0330 00 323 0150 00 315 0331 00 323 0206 00 315 0105 00 321 0032 00 315 0911 00 315 0391 00 315 0152 00 311 0633 00 315 0133 00 315 0131 00 321 0032 00 315 0621 00 321 0122 00 315 0751 00 315 0751 00 321 0356 00 315 0221 00 321 0071 00 323 0255 00 311 0609 00 315 0912 00 315 0123 00 Serial Model Dscont Replaceable Electrical Parts 7A18A Name amp Description RES FXD FILM 383 1 0 125 RES FXD FILM 4 64K 1 0 50 RES FXD FILM 21 OHM 1 0 125W RES FXD CMPSN 626 OHM 5 0 25W RES FXD FILM 182 OHM 1 0 125W RES FXD CMPSN 560 OHM 5 0 25W RES FXD CMPSN 300 OHM 5 0 25W RES FXD CMPSN 560 OHM 5 0 25W RES FXD CMPSN 2 4K OHM 5 0 25W RES FXO FILM 49 9K OHM 1 0 125W RES FXD CMPSN 220 OHM 5 0 25W RES FXD FILM 49 9 OHM 1 0 125W RES FXD FILM 4 42K OHM 1 0 50W RES FXD FILM 200 1 0 125 RES VAR NONWIR TRMR 500 OHM 0 5W RES FXD CMPSN 36K OH
53. 2V Check Check 5V Check Check REV JUN 1983 5 Adjust Channel 1 and 2 High Frequency Compensation a Set the CH 1 and CH2 VOLTS DIV switches to 10 mV b Connect the square wave generator fast rise output to the CH 1 input connector with the 42 inch BNC cable 10X attenuator and in line 50 ohm termination Set the square wave generator for a six division dis play 60 millivolts of 100 kilohertz signal d Set the time base unit for a triggered display at a sweep of 2 microseconds division NOTE In the following steps change the time base unit mag nifier from X1 to X10 and compare the response at both sweep rates e display for optimum square wave re sponse with aberrations not to exceed 0 24 division peak 2 to peak REV JUN 1983 f ADJUST C245 R245 and C275 for optimum square wave response with minimum aberrations Use the low capacitance screwdriver to adjust the variable capaci tors Repeat these adjustments until optimum response is obtained See Fig 4 1 for adjustment location g Disconnect the termination from the CH 1 input con nector and connect it to the CH 2 input connector h Set the DISPLAY MODE switch to CH 2 CHECK CRT display for optimum square wave re sponse with aberrations not to exceed 0 24 division peak to peak ADJUST C445 R445 and C
54. 37 4K OHM 1 0 125W RES FXD CMPSN 150K OHM 5 0 25W RES FXD CMPSN 150K OHM 5 0 25W RES FXD CMPSN 75K OHM 595 0 25 RES FXD CMPSN 75K OHM 5 0 25W RES FXD CMPSN 150K OHM 5 0 25W RES FXD CMPSN 51K OHM 5 0 25W RES FXD FILM 37 4K OHM 1 0 125W RES FXD CMPSN 150K OHM 5 0 25W RES FXD CMPSN 150K OHM 5 0 25W RES FXD CMPSN 13K OHM 5 0 25W RES FXD CMPSN 150K OHM 5 0 25W RES FXD FiLM 75 OHM 1 0 125W RES FXD FILM 54 9 1 0 125 RES FXD FILM 165 OHM 1 0 125W RES VAR NONWIR 2 5K OHM 10 0 50W RES FXD FiLM 130 OHM 1 0 125W RES FXD FILM 69 8 OHM 1 0 125W RES VAR NONWIR 1K OHM 10 0 50W RES FXD FILM 4 53K OHM 195 0 125W RES 5 100 OHM 5 0 25W RES FXD FILM 1 91K OHM 1 0 125W RES FXD FILM 52 3 OHM 1 0 125W RES FXD FILM 52 3 OHM 1 0 125W RES FXD CMPSN 24K OHM 5 0 25W RES FXD FILM 4 53K OHM 1 0 125W CONTACT ELEC CKT BD SW SPR CU BE QUANTITY OF 3 MICROCIRCUIT LEDUAL OPNL AMPL SCREENED Mir Code 80009 04222 12969 12969 12969 12969 12969 12969 12969 12969 12969 12969 03508 57668 91637 91637 57668 57668 57668 57668 57668 91637 57668 57668 57668 57668 57668 57668 91637 57668 57668 57668 57668 91637 91637 91637 01121 91637 91637 01121 91637 57668 91637 57668 57668 57668 91637 80009 01295 Mfr Part Number 670 7667 00 SR302E105ZAA 263 1 4152 NDP0263 1N4152 NDPO263 1N4152
55. 37 MFF1816G21R00F A2R325 315 0621 00 RES FXD CMPSN 620 OHM 5 0 25W 57668 NTR25J E620E A2H326 321 0122 00 RES FXD FILM 182 OHM 1 0 425W 91637 CMF55116G182R0F A2R327 315 0431 00 RES FXD CMPSN 430 OHM 5 0 25W 57668 25 430E 2 A2R340 321 0356 00 RES FXD FILM 49 9K OHM 1 0 125W 91637 MFF1816G49901F A2R341 315 0221 00 RES FXD CMPSN 220 OHM 5 0 25W 57668 NTR25J E220E A2R342 321 0068 00 RES FXD FILM 49 9 OHM 196 0 125W 91637 CMF55116G49R90F A2R343 323 0255 00 RES FXD FILM 4 42K OHM 1 0 50W 75042 CECTO 4421F A2R345 315 0363 00 FXD CMPSN 36K OHM 5 0 25W 57668 NTR2SJ ES6KO A2R350 323 0153 00 RES FXD FILM 383 OHM 1 0 50W 24546 NAG65DS3830F A2R351 321 0137 00 RES FXD FILM 261 OHM 1 0 125W 31637 MFF1816G261R0F A2R351 321 0137 00 RES FXD FILM 261 0HM 1 0 125W 91637 MFF1816G261RO0F A2R356 315 0471 00 RES FXD CMPSN 470 5 0 25 57668 NTR25J E470E A2R357 315 0204 00 RES FXD CMPSN 200K OHM 596 0 25W 57668 NTR25J E 200K A2R359 315 0122 00 RES FXD CMPSN 1 2K OHM 596 0 25W 57668 NTR25J EO1K2 A2R363 315 0272 00 RES FXD CMPSN 2 7K OHM 596 0 25W 57668 NTR25J E02K7 A2R364 315 0330 00 RES FXD CMPSN 33 OHM 5 0 25W 57668 NTR25J E A2R370 321 0217 00 RES FXD FILM 1 78K OHM 1 0 125W 91637 CMF55116G17800F A2R374 315 0242 00 RES FXD CMPSN 2 4K OHM 5 0 25W 57668 NTR25J E02K4 A2R375 315 0100 00 RES FXD CMPSN 10 OHM 5 0 25W 57668 NTR25J E 1060 28376 321 0059 00 RES FXD FILM 40 2 OHM 1 0 125W 91637 CMF55116G50R20F
56. 375 for optimum square wave response with minimum aberrations Use the low capacitance screwdriver to adjust the variable capaci tors Repeat these adjustments until optimum response is obtained See Fig 4 1 for adjustment location This completes the Calilbration of the 7A18A Disconnect all test equipment Replace the left side shield on the 7A18A and the left side panel on the Indicator Oscilloscope 4 11 f alihratinn 7 A 18 BULLY TUE introduction This section of the manual contains maintenance infor mation for use in preventive maintenance corrective mainte nance and troubleshooting of the 7A18A Further maintenance information relating to component color codes and soldering techniques can be found in the instruction manuals for the 7000 series oscilloscopes PREVENTIVE MAINTENANCE General Preventive maintenance consisting of cleaning visual in spection lubrication etc performed on a regular basis will improve the reliability of this instrument Periodic checks on the semiconductor devices used in the unit are not recom mended as a preventive maintenance measure See semi conductor checking shooting Cleaning CAUTION Avoid the use of chemical cleaning agents which might damage the plastics in this instrument Avoid chemicals containing benzene toluene x
57. 4 20 X 0 75 L PNH STL CD PL 93907 ORD BY DESCR BRKT ANGLE VAR RESISTOR ALUMINUM 80009 497 1565 00 SCREW MACHINE 2 56 X 0 562 PNH STL 83385 ORD BY DESCR WASHER LOCK 0 261 ID INTL 0 018 THK BRS 77900 1214 05 00 0541C RESISTOR VAR SEE R12 R22 REPL POST ELEC MECH HEX 0 333 INCH LONG 80009 129 0299 00 SPACER SLEEVE 0 375 L X 0 125 ID AL 71590 P7610 1 WASHER LOCK 4 INTL 0 015 THK STL CD PL 77900 1204 00 000541C CKT BOARD ASSY AMPLIFIER SEE A2 REPL 9 7 miim Rie Tektronix Serial Model Mfr No Dscont Qty 12345 Name amp Description Code Mfr Part Number STANDARD ACCESSORIES 070 4329 00 1 MANUAL TECH INSTRUCTION 80009 070 4329 00 7A18A DUAL TRACE AMPLIFIER 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 developed 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 single change may affect several sections Sincethe change information sheets are carried in the manual until all changes are permanently entered some duplication may occur If no such change pages appear following this page your manual is correct as printed
58. 50 inch hex key wrench Pull the VARIABLE knob and shaft from the front of the instrument 5 Loosen the front hex socket screw in the coupling be tween the DISPLAY MODE and TRIGGER SOURCE switch sections Pull the TRIGGER SOURCE knob and long shaft from the front of the instrument 6 Loosen the front hex socket screw in the coupling of the DISPLAY MODE switch shaft using a 5 16 inch hex key wrench Pull the DISPLAY MODE knob and long shaft from the front of the instrument Maintenance 7A18A 7 Disconnect the resistor capacitor combinations con nected to the ceramic strips at the front of the board 8 Remove the screws and nuts securing the board to the chassis or other mounting surface 9 Remove the board from the instrument 10 To replace reverse the order of removal Switch Replacement Several types of switches are used in the 7A18A The following special maintenance information is provided for the cam type switches and rotary switches A CAM TYPE SWITCHES Repair of cam type switches should be undertaken only by experienced maintenance personnel Switch alignment and spring tension of the contacts must be carefully maintained for proper operation of the switch For assistance in maintenance of the cam type switches contact your local Tektronix Field fice or representative B ROTARY SWITCHES Single wafers on the DISPLAY MODE and TRIGGER SOURCE switches are not normally replaced if any part of
59. 61 0515 00 111 214 1190 02 2 RGD 0 125 OD TO 0 081 00 4L 80009 214 1190 02 112 214 1136 00 2 ACTUATOR SL SW DUAL DPST 80009 214 1136 00 113 351 0180 00 2 SUDE GUIDE SWITCH ACTUATOR 80009 351 0180 00 114 6 CONTACT ELEC CKT BD SW SPR CU BE M SEE 5667 REPL 115 376 0152 00 2 CPLG SHAFT RGD 0 078 amp 0 125 ID AL 80008 376 0152 00 116 354 0251 00 4 RING COUPLING 0 251 ID X 0 375 INCH OD AL 80009 354 0251 00 117 376 0125 00 2 SW 80009 376 0125 00 118 376 0124 00 2 ARM SWITCH ACTR DRIVER 80009 376 0124 00 119 384 1178 00 1 EXTENSION SHAFT 0 123 OD X 6 1 INCH LONG 80009 384 1178 00 120 384 1388 00 1 EXTENSION SHAFT 3 02 1 X 0 078 OD SST PSVT 80009 384 1388 00 121 386 1402 00 1 PANEL REAR 80009 386 1402 00 rer ATTACHING 122 213 0793 00 4 SCREW TPG TF 6 32 X 0 4375 TAPTITE FIL 93907 ORD BY DESCR END ATTACHING PARTS 123 220 0547 01 4 NUT BLOCK 0 38 X 0 26 X 0 282 2 4 40 000FW ORD BY DESCR eee ATTACHING PARTSy emm 124 211 0105 00 4 SCREW MACHINE 4 40 X 0 188 100 DEG FLH ST 83385 ORD BY DESCR ATTACHING PARTS 125 426 0736 00 1 FR SECT PLUG IN TOP 80008 426 0736 00 126 426 0737 00 1 FR SECT PLUG IN BOTTOM 80009 426 0737 00 127 175 7208 00 1 ASSY SP ELEC 2 26 3 0 L RIBBON 80009 175 7208 00 128 352 0169 08 2 HLDR TERM CONN 2 WIRE GRAY 80009 352 0169 08 129 175 7209 00 1 ASSY SP ELEC 2 26 AWG 10
60. 63 00 352 0164 03 MAR 1985 7A18A DUAL TRACE AMPLIFIER REV SEP 1983 7A18A DUAL TRACE AMPLIFIER a Fig amp gt Index No 2 1 Tektronix Part No 366 1319 02 213 0075 00 333 1411 02 384 1313 00 211 0101 00 195 0226 00 376 0039 00 210 0405 00 426 0261 00 166 0251 00 105 0296 00 210 0583 00 211 0008 00 213 0810 00 407 1566 00 211 0081 00 210 0046 00 129 0299 00 166 0026 00 210 0004 00 REV MAR 1985 Serial Modei No Dscont 8010100 8 011599 B011600 8010100 8011599 8011600 Qty 2 PO d PO d PO BM TO nn Me PACA WECULTOTIIGGE I cli UPS Mfr 12345 Name amp Description Code Mfr Part Number KNOB GY 0 79 0 28 OD 0 32 H 80009 366 1319 02 SETSCREW 4 40 X 0 094 STL BK OXD HEX O00BK ORD BY DESCR PANEL FRONT 80009 333 1411 02 RESISTOR VAR SEE R11 R21 REPL EXTENSION SHAFT 9 85 X 0 123 OD EPOXY GLAS 10588 ORD BY DESCR SCREW MACHINE 4 40 X 0 25 FLH 100 DEG STL 83385 ORD BY DESCR WIRE SET ELEC 80009 195 0226 00 ADPT SHAFT CPLG 0 128 AND 0 082 DIA SHAFT 80009 376 0039 00 PLAIN HEX 2 56 X 0 188 BRS CD PL 73743 12157 50 MOUNT RESILIENT 80009 426 0261 00 SPACER SLEEVE 0 125 ID X 0 297 INCH LONG 80009 166 0251 00 BRAKE SHAFT VARIABLE RESISTOR 89009 105 0296 00 NUT PLAIN 0 25 32 X 0 312 INCH BRS 73743 2X20317 402 SCREW MACHINE 4 40 X 0 250 PNH STL POZ 83385 ORD BY DESCR SCREW
61. 91637 57668 57668 57668 57668 57668 57668 57668 91637 91637 24546 57668 91637 57668 75042 57668 91637 57668 57668 57668 73138 57668 57668 91637 57668 91637 57668 57668 91637 57668 91637 75042 73138 57668 57668 Mfr Part Number CMF55116G383ROF MFF1226G46400F MFF1816G21R00F NTR25J E620E CMF557 16G182ROF NTRERJ E 560 NTR25J E300E NTRERJ E 560E NTR25J E02K4 MFF1816G49901F NTR25J E220E CMF55116G49R90F CECTO 4421F CMF55116G200RO0F _ 3329 1 58 501 NTR25J E36K0 NTR25J E20K0 CMF554 16G137RO0F MFF1816G261ROF NTR25J E02K7 NTR25J E470E NTR25J E10K0 NTR25J E 100E NTR25J EO2K7 NTR25J E NTR25J E1K8 CMF55116G50R20F CMF55116G50R20F NA65 9080F NTR25J E MFF1226G357ROF NTR25J E330E CECTO 1371F 255 1M MFF1816G21R00F NTR25J E910E NTR25J E390E NTR25J E01K5 82PR5K 30C NTR25J E 13K NTR25J E 130 MFF1816G21R00F NTR25J E620E CMF55116G182R0F NTR25J E750E NTR25J E750E MFF1816G49901F NTR25J E220E MFF1816G53R60F CECTO 4421F 82 26 1 NTR25J EO9K1 NTR25J E12K0 Replaceable Electrical Parts 7A18A Tektronix Serial Model No Part Dscont Name amp Description Code Part Number 000 Mir Part Number A2R550 323 0153 00 RES FXD FILM 383 OHM 196 0 50W 24546 NA65D3830F A2R551 321 0137 00 RES FXD FILM 261 0HM 1 0 125W 91637 MFF1816G261RO0F A2R555 315 0272 00 RES FXD
62. A2R377 321 0059 00 RES FXD FILM 40 2 0HM 1 0 125W 91637 CMF55116G50R20F A2R378 323 0189 00 RES FXD FILM 909 OHM 196 0 50W 24546 NA65 9090F A2R380 315 0330 00 RES FXD CMPSN 33 OHM 5 0 25W 57668 NTR25J E A2R382 323 0150 00 HES FXD FILM 357 OHM 196 0 50W 91637 MFF1226G357 ROF A2R384 315 0271 00 RES FXD CMPSN 270 OHM 5 0 25W 01121 CB2715 A2R386 323 0206 00 RES FXD FILM 1 37K OHM 1 0 50W 75042 1371 A2R390 315 0470 00 RES FXD CMPSN 47 OHM 5 0 25W 57668 NTR25J E47EO A2R400 315 0152 00 FXD CMPSN 1 5K 0HM 5 0 25W 57668 NTR25J EO1K5 A2R401 315 0101 00 RES FXD CMPSN 100 OHM 5 0 25W 57668 NTR25J E 100 A2R410 316 0474 00 RES FXD CMPSN 470K OHM 10 0 25W 01121 CB4741 A2R411 315 0470 00 RES FXD CMPSN 47 OHM 5 0 25W 57668 NTR25J E47E0 A2R412 315 0561 00 RES FXD CMPSN 560 OHM 595 0 25W 57668 NTRERJ E 560E A2R415 315 0391 00 RES FXD CMPSN 390 OHM 5 0 25W 57668 NTR25J E390E A2R416 315 091 1 00 RES FXD CMPSN 910 OHM 595 0 25W 57668 NTR25J E910E A2H418 321 0032 00 RES FXD FILM 21 OHM 1 0 125W 91637 MFF1816G21 ROOF 7 8 REV MAR 1985 Component A2R422 A2R423 A2R424 A2R425 A2R426 A2R427 A2R428 A2R429 A2R436 A2R440 AZR441 28442 A2R443 A2R444 A2R445 A2R446 A2R449 A2R450 A2R451 A2R455 A2R456 A2H459 A2R460 A2R463 A2R464 A2R474 A2R476 A2R477 A2R478 A2R480 A2R482 A2R484 28486 A2R513 A2R517 A2R518 A2R519 A2R520 A2R521 A2R522 A2R523 A2R524 A2R5
63. ALE 3 CONTACT RES FXD CMPSN 62 OHM 5 0 125W RES VAR NONWIR 5K OHM 1W W SW RES VAR NONWIR OPTION 06 ONLY RES VAR WW PNL 5K OHM 1W OPTION 06 ONLY RES FXD CMPSN 91 5 0 125 RES 5 62 OHM 5 0 125W RES VAR NONWIR 5K OHM 1W W SW RES VAR NONWIR OPTION 06 ONLY RES VAR WW PNL 5K OHM 1W OPTION 06 ONLY RES FXD CMPSN 91 OHM 5 0 125W RES FXD CMPSN 240 OHM 5 0 25W RES FXD CMPSN 620 OHM 5 0 25W RES FXD CMPSN 3 9K OHM 5 0 25W PART OF Rit SWITCH SLIDE DPDT PART OF R21 SWITCH ASSY ATTENUATOR CORE FERRITE 0 196 ID X 0 437 OD CORE FERRITE 0 196 ID X 0 437 0D CORE FERRITE 0 196 ID X 0 437 Mfr Code 80009 80009 80009 80008 59660 80009 80009 59660 59660 80009 80009 59660 59821 24931 24931 80009 12697 12697 02111 01121 89009 12697 12697 02111 01121 57668 57668 57668 82389 80009 01121 01121 01121 Mfr Part Number 307 1010 01 307 1011 00 307 1013 01 307 1014 01 831610Y5U0102P 285 0816 01 285 1132 00 831610Y5U0102P 831610Y5U0102P 285 0816 01 285 1132 00 831610Y5U0102P D10324025UJOCEX 28JR270 1 28JR270 1 317 0620 02 381CM 39700 381CM40360 162 214 9105 317 0620 02 381CM 39700 381 40360 162 214 889105 NTR25J E 240 NTR25J EG20E NTR25J EO3K9 11P 1092 262 1024 00 T037C351A 037 351 037 351
64. AWG 57668 JWW 0200EO0 A2W593 131 0566 00 BUS CONDUCTOR DUMMY RES 2 375 22 AWG 57668 JWW 0200E0 7 10 REV MAR 1985 Component No AT106 AT110 AT114 AT118 C9 C10 C10 C13 Cis C20 C20 C23 C49 J10 J20 R10 R11 R41 R11 R12 R12 R13 22 R20 821 R21 R21 R22 R22 R23 R35 R36 R38 13 22 23 30 111 121 T31 REV MAR 1985 Tektronix Part No 307 1010 01 307 1011 00 307 1013 01 307 1014 01 283 0000 00 285 0816 01 285 1132 00 283 0000 00 283 0000 00 285 0816 01 285 1132 00 283 0000 00 283 0003 00 131 0679 02 131 0679 02 317 0620 02 311 1320 00 311 1144 00 311 0889 00 317 0910 00 317 0620 02 311 1320 00 311 1144 00 317 0910 00 315 0241 00 315 0621 00 315 0392 00 262 1024 00 276 0525 00 276 0525 00 275 0525 00 Serial Model No B010100 B011885 B010100 B011885 Dscont B011884 8011884 Replaceabie Electrical Parts 7A18A Name amp Description CHASSIS PARTS ATTENUATOR FXD 2X ATTENUATOR FXD 4X ATTENUATOR FXD 10X ATTENUATOR FXD 100X CAP FXD CER DI 0 001UF 100 0 500V CAP FXD PLSTC 0 019UF 10 600V CAP FXD PLSTC 0 019UF 10 600V DI 0 001UF 100 0 500V CAP FXD CER DI 0 001UF 100 0 500V CAP FXD PLSTC 0 019UF 10 600V CAP FXD PLSTC 0 01 SUF 10 800V CAP FXD CER DI 0 001UF 100 096 500 CAP FXD CER DI 0 01UF 80 20 150V CONNECTOR RCPT BNC MALE 3 CONTACT CONNECTOR RCPT BNC M
65. CALIBRATION See step 5 of the Adjustment procedure Disconnect test equipment 6 Check Channel 1 and 2 Lower Frequency Response a Change the following contro settings CH 1 and CH 2 VOLTS DIV 5 mV AC GND DC AC b Set the time base unit for a free running sweep at a rate of two milliseconds division c Connect the low frequency constant amplitude sine wave generator to the CH 2 input connector with the 42 inch BNC cable 10X BNC attenuator and 50 ohm BNC termination d Set the low frequency generator for a six division dis play 30 millivolts at 10 kilohertz e Decrease the generator frequency until the display amplitude decreases to 4 2 divisions L CHECK Generator frequency must be 10 hertz less g Disconnect the low frequency generator from the CH 2 input connector and connect it to the CH 1 input connector h Set the DISPLAY MODE switch to CH 1 i Repeat parts d through f of this step for Channel 1 j Disconnect all test equipment 7 Check Channel Isolation a Change the following control settings Palihratinn__FJAIRA CH 7 and CH 2 DC 2 AC GND DC ERTI CH 1 VOLTS DIV IV 2 VOLTS DIV 10 mV b Connect the medium frequency generator to the CH 1 NE input connector with the 42 inch cabie and in line 50 ohm termination Set the generator for a two division display 200 milli volts at 50 megahertz d Change the followi
66. CAP FXD CER DEO 1UF 2095 50V CAP FXD CER D 1000PF 10 100V CAP FXD CER 01 33 5 50 CAP FXD CER DI 1000PF 10 100V CAP FXD CER DI 5 6PF 0 5 100V DI 2 10PF 100V CAP FXD CER DI 100PF 10 100V CAP FXD CER Di 0 1UF 20 50V CAP FXD CER Dt 0 1UF 2095 50V CAP FXD CER DEO 1UF 2095 50V CAP FXD CER Dt 0 1UF 2095 50V CAP FXD CER DE 0 1UF 20 50V CAP FXD CER Di 0 1UF 20 50V CAP FXD CER Di 0 1UF 20 50V CAP FXD CER Di 0 1UF 20 50V CAP FXD CER 01 0 0059 100 0 500 8010100 8011884 Dt 1 8PF 1096 500V 8011885 CAP FXD CER Dl 1 5PF 4 0 25PF 500V CAP FXD ELCTLT 22UF 50 1096 25V CAP FXD CER D1 680PF 1096 50V FXD CER D1 1000PF 10 100V CAP FXD CER Dt 1000PF 10 100V CAP FXD CER DI 1000PF 10 100V VAR CER DI 2 10PF 100V CAP FXD GER DI 0 1UF 20 50V CAP FXD CER DI 1600PF 10 100V CAP FXD CER DE1000PF 10 100 Mfr Code 80009 80009 80008 80009 59821 04222 04222 54473 05397 04222 59660 96733 04222 04222 72982 04222 04222 59660 04222 04222 54473 05397 04222 04222 04222 72982 04222 04222 59650 04222 04222 04222 04222 04222 04222 04222 04222 04222 59821 04222 04222 54473 05397 04222 04222 04222 59660 04222 04222 04222 Mfr Part Number 670 7666 00 670 7666 02 670 7666 01 670 7666 03 2DDH61L502P 7001 COK 1R8B 7001 1 5 ECE A25V22L C114K681K1X5CA MA101C102KAA
67. CMPSN 2 7K 5 0 25 57668 NTR25J E02K7 28556 315 0471 00 RES FXD CMPSN 470 OHM 5 0 25W 57668 NTR25J E470E A2R557 315 0204 00 RES FXD CMPSN 200K OHM 596 0 25W 57668 NTR25J E 200K A2R559 315 0122 00 RES FXD CMPSN 1 2K OHM 5 0 25W 57668 NTR25J EO1K2 A2R563 315 0272 00 RES FXD CMPSN 2 7K OHM 5 0 25W 57668 NTR25J E02K7 A2R564 315 0330 00 RES FXD CMPSN 33 OHM 596 0 25W 57668 NTR25J E 33E A2R570 321 0217 00 RES FXD FILM 1 78K OHM 1 0 125W 91637 CMF55116G17800F A2R574 315 0182 00 RES FXD CMPSN 1 8K OHM 5 0 25W 57668 NTR25J E1K8 A2R576 321 0059 00 RES FXD FILM 40 2 OHM 195 0 125W 91637 CMF55116G50R20F A2R577 321 0059 00 RES FXD FILM 40 2 0HM 1 0 125W 91637 CMF55116G50R20F 2 578 323 0189 00 RES FXD FILM 909 OHM 1 0 50W 24546 65 9090F A2R580 315 0330 00 RES FXD CMPSN 33 OHM 5 0 25W 57668 NTR25J E A2R582 323 04 50 60 RES FXD FH M 357 OHM 1 0 50W 91637 MFF1226G357ROF A2R584 315 0331 00 RES FXD CMPSN 330 OHM 5 0 25W 57668 NTR25J E330E 28586 323 0206 00 RES FXD FILM 1 37K OHM 1 0 50W 75042 1371 A2R590 315 0470 00 RES FXD CMPSN 47 OHM 5 0 25W 57668 NTR25J E47E0 A2U270 155 0022 00 MICROCIRCUIT DI ML CHANNEL SWITCH 80009 155 0022 00 20470 155 0022 00 MICROCIRCUIT DI ML CHANNEL SWITCH 80009 155 0022 00 2VV391 131 0566 00 BUS CONDUCTOR DUMMY RES 2 375 22 AWG 57668 JWW 0200E0 A2W393 131 0566 00 BUS CONDUCTOR DUMMY RES 2 375 22 AWG 57668 JWW 0200E0 A2W591 131 0566 00 BUS CONDUCTOR DUMMY RES 2 375 22
68. CMPSN 9 1K OHM 5 0 25W NOMINAL VALUE SELECTED 4 7K 100K MAX RES FXD CMPSN 20K 5 0 25 RES FXD FILM 121 OHM 1 0 125W RES FXD FILM 261 OHM 1 0 125W RES FXD CMPSN 470 OHM 5 0 25W RES FXD CMPSN 15K OHM 5 0 25W RES FXD CMPSN 10K OHM 5 0 25W RES FXD CMPSN 100 OHM 5 0 25W Mfr Code 04713 04713 80009 07263 80008 22228 80009 04713 04713 17856 80009 80009 80009 80009 22229 80009 04713 04713 80009 80009 80009 80009 22229 80009 04713 04713 01121 57668 57668 57668 57668 91637 91637 91637 91637 57668 91637 57668 57668 91637 57668 91637 75042 91637 32997 57668 57668 91637 91637 57668 57668 57668 57668 Mfr Part Number SRF501 SPS246 153 0631 00 39291 153 0597 00 82114 153 0597 00 SRF501 SPS246 DN399 153 0631 00 153 0595 00 153 0595 00 153 0597 00 52114 153 0597 00 SRF501 SPS246 153 0631 00 153 0595 00 153 0595 00 153 0597 00 52114 153 0597 00 SRF501 SPS246 CB4741 NTR28J E47EO0 NTRERJ E 560E NTR25J ES90E NTR25J E910E MFF1816G21 ROOF CMF55116G383ROF MFF1226G46400F MFF1816G21R00F NTR25J E620E CMF55116G182ROF NTRERJ E 560 NTR25J E02K4 MFF1816G49901F NTR25J E220E CMF55116G49R90F 4421 CMF55116G200ROF 3329H L58 501 NTR25J E09K1 NTR25J E20K0 CMF55116G121RO0F MFF1816G261RO0F NTR25J E470E NTR25J E 15K NTR25J E10KQ0 NTR25J E 100 Replaceable Electrical Parts 7A18A Serial
69. CONTROLS SECOND CASCODE EMITTER AMPLIFIER FOLLOWER TO SIGNAL CHANNEL SWITCH U270 TO TRIGGER CHANNEL SWITCH RON 0470 S23 1126 45 4329 21 Fig 3 2 Channel 2 Input Amplifier detailed block diagram a means of inverting the displayed signal With the CH 2 POLARITY switch set to UP 0426 and 0526 are biased on and the signal is passed to the Second Cascode Amplifi er stage as for the Channel 1 Input Amplifier With the CH 2 POLARITY switch set to INVERT Q426 and Q526 are bi ased off and Q425 Q525 are turned on to provide signal inversion Second Cascode Amplifier The Second Cascode Amplifier consists of Q440 Q540 Q450 and Q550 Position of the trace is set by the POSI TION control R21 or by network R455 R555 as determined by the DISPLAY MODE switch In any DISPLAY MODE Switch position other than ADD 50 volts is applied to the center arm of the POSITION control through R549 The PO SITION control varies the current drive to the emitters of Q450 Q550 Since the emitters are a very low impedance point in the circuit there is negligible voltage change at these points However the change in current from the PO SITION control produces a resultant dc voltage difference at the collectors to change the position of the trace When the DISPLAY MODE switch is in the ADD position 50 volts is applied to the junction of resistors R455 R555 through R549 to balance the current drive to the emitters
70. E MERGE ZY any FNL Vena Y 182 N98 1000Y33 4 lt gt 659 pa ls 064 LR lt THO LU TAN 6190 tASI m ASIE D aw AdILNS n LN SOs THT Fi TES gt 7 oLh 72930 M 8 red du a CD OESTE er Ott is v AIG GLIOA oz AU o INTERFACE CONNECTIONS P O A2 ASSY interface Connections lt gt Circuit Schematic Board Circuit Schematic Board Number Location Location Number v Location Location INTERFACE gt SNOILOANNOD IOVISILNT ANO Aviad 351 Spey 82140913 je pua 285 sequen A gwassy 0 JOQUAN Argurassegng dogun 7 Aguossy 3429495 ER 96218 aaaea Jaquiny 11 VMVX3 939VVIM 1M3M0 V0 0129 aeg SODIAS SANSUSS 211215 iN BAG BAYNE LTY Aylad AM a INDIO ans NOS Ni asina A1907 S3Wl i m WING DOTINY THD II oz Wow
71. Frequency 2 Hz to 10 kHz output Triggering check TEKTRONIX FG 503 generator amplitude 10 mV to 400 mV p p Function Generator Square wave Output capabilities 12 V into 50 0 with Input and low frequency TEKTRONIX PG 506 generator risetime of at least 12 ns and a frequency compensation adjustments Pulse Generator of approximately 1 kHz 500 mV into 50 0 with a risetime of at least 1 ns to 100 kHz Plug in Extender Provides access to 7A18A adjustments Used for aberrations check Tektronix Calibration Fixture 067 0589 00 Accessories BNC cable Connectors BNC length 42 inches Used throughout Tektronix Part Number t Gd procedure 012 0057 01 10X attenuator Connectors BNC impedance 50 Q High frequency Tektronix Part Number compensation 011 0059 02 RC normalizer Time constant 1 x 20 pF connector Input compensation Tektronix Part Number BNC attenuation 2X 067 0538 00 Termination through Impedance 50 9 connectors GR to Used throughout Tektronix Part Number tine male procedure 017 0083 00 Dual Input cable Connectors BNC matched signal Common mode rejection Tektronix Calibration transfer to each input Fixture 067 0525 01 4 2 REV JUN 1983 Table 4 1 cont Description Adjustment tools Screwdriver Three inch shaft 3 32 inch bit Low capacitance 1 1 2 inch shaft Screwdriver Tuning tool Handle with inserts tRequired only for Performance Check Required
72. GGER SIGNAL SOURCE CH 1 Channel 1 CH 2 Channei 2 ADD Algebraic sum of channel 1 and channel 2 CHOP Algebraic sum of channel 1 and channel 2 ALT Alternates between channel 1 and channel 2 Trace Identification When the IDENTIFY button is pressed the trace is de flected about 0 3 division to identify the 7A18A trace This feature is particularly useful when multiple traces are dis played In instruments with readout also replaces deflection factor readout with the word Identify BASIC APPLICATIONS General The following information describes the procedures and techniques for making basic measurements with a 7A18A and the associated Tektronix oscilloscope and time base These applications are not described in detail since each application must be adapted to the requirements of the indi vidual measurements This instrument can also be used for many appliactions not described in this manual Contact your local Tektronix Field Office or representative for assis tance in making specific measurements with this instrument Peak to Peak Voltage Measurements AC To make peak to peak voltage measurements use the following procedure 1 Apply the signal to either input connector 24 E ay M MH 2 Set the DISPLAY MODE and TRIGGER SOURCE switches to display the channel used 3 Set the coupling switch to AC NOTE For low frequency signals below about 30 Hz use the dc position to prevent attenuation of the signal
73. M 576 0 25W RES FXD CMPSN 20K OHM 5 0 25W RES FXD FILM 137 OHM 1 0 125W RES FXD FILM 261 OHM 1 0 125W RES FXD CMPSN 2 7K OHM 5 0 25W RES FXD CMPSN 470 OHM 5 0 25W RES FXD CMPSN 10K OHM 5 0 25W RES FXD CMPSN 100 OHM 5 0 25W RES FXD CMPSN 2 7K OHM 5 0 25W RES FXD CMPSN 33 OHM 5 0 25W RES FXD CMPSN 1 8K 5 0 25 RES FXD FILM 40 2 OHM 1 0 125W RES FXD FILM 40 2 OHM 1 0 125W RES FXD FILM 909 OHM 1 0 50W RES 33 OHM 5 0 25W RES FXD FILM 357 OHM 1 0 50W RES FXD CMPSN 330 OHM 5 0 25W RES FXD FILM 1 37K OHM 1 0 50W RES FXD CMPSN IM OHM 5 0 25W RES FXD FiLM 21 OHM 1 0 125W RES FXD CMPSN 910 OHM 5 0 25W RES 390 OHM 5 0 25W RES FXD CMPSN 1 5K OHM 5 0 25W RES VAR NONWIR 5K OHM 10 0 50W RES FXD CMPSN 13K OHM 5 0 25W RES FXD CMPSN 130 OHM 5 0 25W RES FXD FILM 21 OHM 1 0 125W RES FXD CMPSN 620 OHM 5 0 25W RES FXD FILM 182 OHM 1 0 125W RES FXD CMPSN 750 OHM 5 0 25W RES FXD CMPSN 750 OHM 5 0 25W RES FXD FILM 49 9K OHM 1 0 125W RES FXD CMPSN 220 OHM 575 0 25W RES FXD FILM 53 6 OHM 1 0 125W RES FXD FILM 4 42K OHM 1 0 50W RES VAR NONWIR 2K OHM 10 0 50W RES FXD CMPSN 9 1K OHM 5 0 25W NOMINAL VALUE SELECTED 4 7K 100K MAX RES FXD CMPSN 12K OHM 596 0 25W Mfr Code 91637 91637 91637 57668 91637 57668 57668 57668 57668 91637 57668 91637 75042 91637 32997 57668 57668 91637
74. ND CIRCUIT BOARD ILLUSTRATIONS Symbols Symbols and Reference Designators Voltage and Waveform Conditions MECHANICAL PARTS LIST Mechanical Parts List information Index of Mechanical Parts lilustrations Mechanical Parts List Accessories CHANGE INFORMATION Abbreviations and symbols used in this manual are based on or taken directly from IEEE Standards 260 Standard Symbols for Units MIL STD 12B and other standards of the electronics industry Change information if any is locat ed at the rear of this manual LIST OF ILLUSTRATIONS Fig No 2 1 2 2 2 3 2 4 2 5 2 6 5 1 6 1 6 2 6 3 Page Front panel controls and connectors 2 1 Measuring the peak to peak voltage of a Waveform 2 4 Measuring instantaneous voltage with respect to some reference 2 5 Measuring phase difference betwen two uada CES S RE DUE An 2 7 High resolution phase measurment using time base magnifier 2 7 Using the ADD mode for common mode TOBEION vxo ores hs te vua wee ke e ka 2 8 Channel 1 Input Amplifier detailed block A 3 2 Channel 2 Input Amplifier detailed block diagram PER E 3 4 U270 input combinations for DISPLAY MODE selection 3 5 input Output combinations for DISPLAY MODE and TRIGGER SOURCE switch selections _ __ ___ 3 5 Locations of adjustments used in this proce
75. PARTS 35 200 1 199 04 2 COV ATTEN 5 80009 200 1199 04 free ATTACHING 7m 36 211 0007 00 8 SCREW MACHINE 4 40 X 0 188 PNH STL CD PL 83385 ORD BY DESCR 37 210 0004 00 8 WASHER LOCK 4 INTL 0 015 THK STL PL 77900 1204 00 000541C END ATTACHING PARTS 38 337 1423 05 2 SHIELD ELEC ATTENUATOR 80009 337 1423 05 Be ATTACHING PARTS p meee 39 213 0055 00 2 SCR TPG THD FOR 2 32 0 188 INCH PNH STL 93907 ORD BY DESCR rm END ATTACHING PARTS 40 407 0906 00 1 BRKT CKT BD BRASS CU SN ZN 80009 407 0906 00 B eee ATTACHING PARTS 1 At 210 0586 00 2 NUT PL ASSEM WA 4 40 X 0 25 STL CD PL T0435 ORD BY DESCR 42 211 0008 00 4 SCREW MACHINE 4 40 X 0 250 PNH STL POZ 83385 ORD BY DESCR aree END ATTACHING PARTSy mm REV MAR 1985 i 3 3 Replaceable Mechanical Parts 7A18A Fig amp index No 1 43 44 45 46 47 49 61 62 63 64 65 66 67 68 77 78 79 80 81 82 83 84 85 86 87 88 9 4 Tektronix Part No 211 0008 00 214 0579 00 124 0162 00 355 0046 00 136 0729 00 200 0945 01 211 0001 00 200 0945 00 136 0252 07 131 0608 00 407 0912 00 214 1061 00 129 0554 01 211 0008 00 213 0912 00 210 0590 00 210 0012 00 175 3093 00 352 0169 00 175 6178 00 352 0169 05 175 6998 00 352 0163 00 175 5414 00 352 0165 08 441 0992 04 211 0097 00 210 0004 00 129 0299 00 210 0004 00 210 0405 00 211 0001 00 2
76. PLACEMENT PARTS Standard Parts All electrical and mechanical part replacements for the 7A18A can be obtained through your local Tektronix Field Office or representative However many of the standard electronic components can be obtained locally in less time than is required to order them from Tektronix Inc Before purchasing or ordering replacement parts check the parts lists for value tolerance rating and description 5 3 When selecting replacement parts it is important to remember that the physical size and shape of the component may affect its performance in the instru ment All replacement parts should be direct replace ments unless it is known that a different component will not adversely affect the instrument performance Special Parts Some parts are manufactured or selected by Tektronix to satisfy particular requirements or are manufactured for Tektronix to our specifications These special parts are indi cated in the parts list by an asterisk preceding the part num ber Most of the mechanical parts used in this instrument have been manufactured by Tektronix Order all special parts directly from your local Tektronix Field Office or representative Ordering Parts When ordering replacement parts from Tektronix inc refer to the Parts Ordering Information and Special Notes and Symbols on the page immediately preceding the Electri cal Parts List section Include the fol
77. SY SP ELEC 26 AWG 4 0 L RIBBON HLDR TERM CONN 5 WIRE BLACK ASSY SP ELEC 7 26 AWG 3 5 L RIBBON HLDR TERM CONN 7 WIRE WHITE CKT BD ASSY CAM SW amp READOUT SEE A1 REPL CHAS PL IN UNIT ATTENUATOR Qtr ri ATTACHING PARTS SCREW MACHINE 4 40 X 0 312 INCH PNH STL WASHER LOCK s4 INTL 0 015 THK STL CD PL POST ELEC MECH HEX 0 333 INCH LONG WASHER LOCK 4 INTL 0 015 THK STL CD PL NUT PLAIN HEX 2 56 X 0 188 BRS CD PL SCREW MACHINE 2 56 X 0 25 INCH PNH STL WASHER EOCK 2 SPLIT 0 02THK STL CAD PL WASHER FLAT 0 09 1D X 0 25 INCH OD BRS a END ATTACHING PARTSy BOARD ASSY ATTENUATOR SEE A1A1 REPL CONTACT ASSY EL CAM SWITCH TOP ASSY ELEC CAM SWITCH BOTTOM CONTACT ELEC 0 178 INCH LONG SOCKET PIN TERM U W 0 03 DIA PINS EYELET METALLIC 0 047 OD X 0 133 L BRASS SHLD ELECTRICAL CAM CONTACTS SW CAM ACTR ASSY VOLTS DIV SEE A1A2 REPL Sere ATTACHING SCR ASSEM WSHR 4 40 X 0 29 885 NI PL CONTACT ELEC GROUNDING CU ALBALOY PL END ATTACHING 5 CAM SWITCH ASSY INCLUDES ACTUATOR SWITCH AC DC ee ATTACHING PARTS SCREW CAP SCH 2 56 X 0 375 HEX HD STL SEND ATTACHING PARTS Mfr Code 83385 80009 80009 80009 09922 80009 87308 80009 22526 22526 80009 80009 80009 83385 72228 73743 77900 80009 80009 80009 80009 80009 80009 80009 89009 80009 83385 77900 80009 77900 73743 87308 12327 800
78. TLE BEACH SC 29577 04713 MOTOROLA INC SEMICONDUCTOR PROD DIV 5005 E MCDOWELL RD PO BOX 20923 PHOENIX AZ 85036 05397 UNION CARBIDE CORPORATION MATERIALS SYSTEMS DIVISION 11901 MADISON AVENUE CLEVELAND OH 44101 07263 FAIRCHILD SEMICONDUCTOR DIV OF FAIRCHILD CAMERA AND INSTRUMENT CORP 464 ELLIS STREET MOUNTAIN VIEW CA 94042 12697 CLAROSTAT MFG CO INC LOWER WASHINGTON STREET DOVER NH 03820 12969 UNITRODE CORPORATION 580 PLEASANT STREET WATERTOWN MA 02172 17856 SILICONIX INC 2201 LAURELWOOD DRIVE SANTA CLARA CA 95054 22229 SOLITRON DEVICES INC SEMICONDUCTOR GROUP 8808 BALBOA AVENUE SAN DIEGO OPERS CA 92123 24546 CORNING GLASS WORKS ELECTRONIC COMPONENTS DIVISION 550 HIGH STREET BRADFORD PA 16701 24931 SPECIALITY CONNECTOR CO INC 2620 ENDRESS PLACE GREENWOOD IN 46142 32997 BOURNS INC TRIMPOT PRODUCTS DIV 1200 COLUMBIA AVE RIVERSIDE CA 92507 34430 MONSANTO COMMERCIAL PRODUCT CO FABRICATOR PRODUCTS DIV BOX 3790 611 EAST CERRITOS AVE ANAHEIM 92803 54473 MATSUSHITA ELECTRIC CORP OF AMERICA PANASONIO WAY SECAUCUS NJ 07094 57668 R OHM CORP 16931 MILLIKEN AVE IRVINE CA 92713 59660 TUSONIX INC 2155 N FORBES BLVD TUCSON AZ 85705 59821 CENTRALAB INC 7158 MERCHANT AVE EL PASO TX 79915 SUB NORTH AMERICAN PHILIPS CORP 72982 ERIE TECHNOLOGICAL PRODUCTS INC 644 W 12TH ST ERIE PA 16512 73138 BECKMAN INSTRUMENTS INC HELIPOT DW 2500 HARBOR BLVD FULLERTON CA 92634 74970 JOHNSON E F CO 299
79. Tektronix inc P O Box 500 Beaverton Oregon 070 4329 00 Product Group 42 97077 troni COMMITTED TO EXCELLENCE PLEASE CHECK FOR CHANGE INFORMATION AT THE REAR OF THIS MANUAL DUAL TRACE AMPLIFIER INSTRUCTION MANUAL Serial Number First Printing OCT 1982 Revised MAR 1985 Copyright 1971 1982 Tektronix Inc Ali rights reserved Contents of this publication may not be reproduced in any form without the written permission of Tektronix Inc Products of Tektronix Inc and its subsidiaries are covered U S and foreign patents and or pending patents TEKTRONIX SCOPE MOBILE and 1 ii are registered trademarks of Tektronix Inc TELEQUIPMENT is a registered trademark of Tektronix U K Limited Printed in U S A Specification and price change privileges are reserved INSTRUMENT SERIAL NUMBERS Each instrument has a serial number on a panel insert tag or stamped on the chassis The first number or letter designates the country of manufacture The five digits of the serial number are assigned sequentially unique to each instrument Those manufactured in the United States have six unique digits The country of manufacture is identified as follows 8000000 Tektronix inc Beaverton Oregon USA 100000 Tektronix Guernsey Ltd Channei Islands 200000 Tektronix United Kingdom Ltd London 300000 Sony Tektronix Japan 700000 Tektronix Holland NV Heerenveen The Ne
80. The Adjustment procedure gives the recommended calibration procedure for all circuits in this instrument Complete Performance Check Adjustment To com pletely check and adjust all parts of this instrument perform both Parts and Il Start the complete procedure by per forming the Adjustment procedure and follow this with the Performance Check This method will assure that the instru ment is both correctly adjusted and performing within Performance Requirements as given in Section 1 TEST EQUIPMENT REQUIRED General The following test equipment and accessories or its equivalent is required for complete calibration of the Specifications given for the test equipment are the minimum necessary for accurate calibration Therefore some of the specifications listed here may be somewhat less precise than the actual performance capabilities of the test equipment test equipment is assumed to be correct ly calibrated and operating within the listed specifications The Performance Check and Adjustment procedures are based on this recommended equipment If other equipment is substituted control settings or calibration setup may need to be altered to meet the requirements of the equipment used Detailed operating instructions for the test equipment are not given in this procedure Refer to the instruction man ual for the test equipment if more information is needed Calibration Equipment Alternatives Ail of the test equ
81. VERSAL PRECISION PRODUCTS Address 105 SE TAYLOR 7923 SW CIRRUS DRIVE 2620 STEVENS DRIVE P O BOX 3608 1201 2ND STREET SOUTH RICHARDS AVENUE 9301 ALLEN DRIVE YOUK EXPRESSWAY 16150 STAGG STREET 2620 ENDRESS PLACE 17383 HEALY P O BOX 858 459 MT PLEASANT 446 MORGAN ST SAINT CHARLES RD ST CHARLES ROAD 47 16 AUSTEL PLACE BOX 500 2530 CRESCENT DR 701 SONORA AVENUE P O BOX 1360 600 18TH AVE 57 CORDIER ST 4114 SOUTH PERORIA AVE 1775 NW 216TH City State Zip PORTLAND OR 97214 BEAVERTON OR 97005 RICHLAND WA 99352 HARRISBURG PA 17105 MILWAUKEE WI 53204 NORWALK CT 06852 CLEVELAND OH 44125 NEW CUMBERLAND PA 17070 VAN NUYS 91409 GREENWOOD IN 46142 DETROIT 48212 FORT DODGE IA 50501 NEW BEDFORD MA 02742 CINCINNATI OH 45206 ELGIN IL 60120 ELGIN iL 60120 LONG ISLAND CITY NY 11101 BEAVERTON OR 97077 BROADVIEW IL 60153 GLENDALE CA 91201 STATESVILLE NC 28677 ROCKFORD li 61101 IRVINGTON NJ 07111 CHICAGO IL 60609 HILLSBORO OR 97123 REV MAR 1985 p AIG Fig amp index Tektronix Serial Model No Part No Dscont 12345 amp Description Code Mfr Part Number 1 1 337 1064 04 8010100 8010450 1 SHIELD ELEC SIDE PLUG IN UNITS 80009 337 1064 00 337 1064 12 8010451 1 SHIELD ELEC SIDE FOR PLUG IN UNIT 80009 337 1064 12 2 366 1077 00 2
82. a 21 7924 ea a 23 ZA i 20 1 0928 29 ex 6929 29 2 13 gr o 23 CV 1 LICH 20 1 LG n 23 vo 6 2 L4 94 14 vd 15 ed v3 Gp2H o va 24 64 29 2 53 1 23 29 ig 23 d 13 CM 23 24 23 93 9629 24 93 sa 1224 23 24 29 9224 29 22 eo vec 28 19 gO ZH 29 93 er 5002297 1042907 2 J8quinN peog IMU pieog lt gt dwy 1 HO ASSY ZY Old Yas Id NY TANNVHO 2 1M9M0 MI05 TEST WAVEFORMS FOR DIAGRAM lt gt THO 0 ANY 32941 ZV NI ia 6590 e Siuvd JO S3ONYH 91 01 0 OL t ALT HAGAN SIMIVA NSIS TS EIER 1511 53 9MV 235 T H2 t amp 992 SIE Speg BY pue 885 Kees GEH 199 OLY
83. ame polarity as the applied signal and a positive dc voltage move the crt trace up In the INVERT position a posi tive going waveform at the CH 2 input will be displayed on the crt in inverted form and a positive dc voltage will move the trace down DISPLAY MODE Switch For single trace operation apply the signal either to the CH 1 input of the CH 2 input and set the DISPLAY MODE switch to the corresponding position CH 1 or CH 2 To display a signal in one channel independently when a signal is also applied to the other channel simply select the desired channel by setting the DISPLAY MODE switch to the appropriate CH 1 or CH 2 position Alternate Mode The ALT position of the DISPLAY MODE switch produces a display which alternates between channel 1 and channel 2 with each sweep on the crt Al though the ALT mode can be used at all sweep rates the CHOP mode provides a more satisfactory display at sweep rates below about 0 2 millisecond division At slow sweep rates alternate mode switching becomes visually perceptible Add The ADD position of the DISPLAY MODE switch can be used to display the sum or difference of two signals for common mode rejection to remove an undesired signal The overall deflection factor in the ADD mode with both VOLTS DIV switches set to the same position is the deflection factor indicated by either VOLTS DIV switch However if the CH 1 and CH 2 VOLTS DIV switches are set to different deflec
84. are used to indicate the setting of the VOLTS DIV switch to the mainframe readout system The VOLTS DIV switch is a cam type switch The dots on the contact closure chart see Diagram 5 indicate when the as sociated contacts are closed R633 R634 and R635 select the number 1 2 or 5 depending on the resistor combination that is switched in R647 selects the m milli prefix and R639 selects the symbol V volts in the 5 mV through 5 V 50 mV positions of the VOLTS DIV switch R638 selects the symbol V in the 1 2 and 5 V positions R630 R631 and the output of the probe sensing stage Q620 select the dec imal point number of zeroes again depending on the resis tor combination switched in by the VOLTS DIV switch Probe sensing stage Q620 identifies the attenuation fac tor of the probe connected to the input connector by sens ing the amount of current flowing from the current sink 3 6 through the probe coding resistance The output of this cir cuit corrects the mainframe readout system to include gt probe attenuation factor The third contact of the input con nector provides the input to the probe sensing stage from the probe coding resistance coded probes only see Oper ating Instructions The third contact is also used for the IDENTIFY input The coding resistor forms a voltage divider with R621 through CR621 to the 15 V supply The resultant voltage sets the bias on Q620 and determines along with
85. ary Control Settings 6 Adjust the Focus and Astigmatism as necessary to obtain a well defined display 4 8 NOTE Titles for external controls of this instrument are capi talized in this procedure e g VOLTS DIV Internal adjustments are initial capitalized only e g DC Balance Location of Adjustments The locations of the 7A18A adjustments are shown in Fig 4 1 1 Adjust Channel 1 and 2 DC Balance a Position the trace to the center horizontal line with the CH 1 POSITION control b Push and release the CH 1 VARIABLE VOLTS DIV control to its outward position c CHECK Turn the VARIABLE control from fully coun terclockwise to fully ciockwise Trace should not move more than 0 5 division vertically d ADJUST Channel 1 DC Balance R321 for minimum trace shift as the CH 1 VARIABLE control is rotated from fully counterclockwise to fully clockwise See Fig 4 1 for adjustment location e Set the CH 1 VARIABLE control to the CAL IN position f Set the DISPLAY MODE switch to CH 2 g Position the trace to the center horizontal line with the CH 2 POSITION control h ADJUST DC BAL R521 for no trace shift while switching CH 2 POLARITY switch from UP to INVERT See Fig 4 1 for adjustment location i ADJUST CH 2 VARIABLE DC BAL R544 for mini mum trace shift as the CH 2 VARIABLE control is rotated from fully counterclockwise to fully clockwise See Fig 4 1 for adjustment location j
86. ates the serial number at which the part was first used Column four 4 indicates the serial number at which the part was removed No serial number entered indicates part is good for all serial numbers NAME amp DESCRIPTION column five of the Electrical Parts List in the Parts List an item Name is separated from the description by a coton Because of space limitations an Name may sometimes appear as incomplete For further item Name identification the U S Federal Cataloging Handbook H6 1 can be utilized where possible MFR CODE column six of the Electrical Parts List indicates the code number of the actual manufacturer of the part Code to name and address cross reference can be found immediately after this page MFR PART NUMBER column seven of the Electrical Parts List Indicates actual manufacturers part number REV FEB 1983 7 1 Cantina TAIRA CROSS CODE NUMBER TO MANUFACTURER Code Manufacturer Address City State Zip 01121 ALLEN BRADLEY COMPANY 1201 2ND STREET SOUTH MILWAUKEE Wi 53204 01295 TEXAS INSTRUMENTS INC SEMICONDUCTOR GROUP BOX 5012 DALLAS TX 75222 02111 SPECTROL ELECTRONICS CORPORATION 17070 EAST GALE AVENUE CITY OF INDUSTRY CA 91745 03508 GENERAL ELECTRIC COMPANY SEMI CONDUCTOR PRODUCTS DEPARTMENT ELECTRONICS PARK SYRACUSE NY 13201 04222 CERAMICS DIVISION OF AVX BOX 867 MYR
87. ation either of the two identical am plifier channels can be used independently by setting the DISPLAY MODE and TRIGGER SOURCE switches to CH 1 of CH 2 and connecting the signal to be observed to the appropriate input In the discussions to follow single trace operations using CH 1 only apply equally to CH 2 only Signal Connections In general probes offer the most convenient means of connecting a signal to the input of the 7A18A A 10X attenu ator probe offers a high input impedance and allows the circuit under test to perform very close to normal operating conditions The TEKTRONIX P6053B probe with its readout coding ring was designed specifically for use with TEKTRONIX 7A series amplifier units equipped with readout The readout coding ring on the probe connects to a circuit in the amplifier unit which automatically corrects the readout displayed on the crt to the actual deflection factor at the tip of the probe being used For probes to be used with amplifier units with out readout see the Tektronix Inc catalog Vertical Gain Check and Adjustment To check the gain of either channel set the VOLTS DIV Switch to 10 mV and connect 40 mV 1 kHz signal from the oscilloscope calibrator to the input connector of the channel being checked The vertical deflection should be exactly four divisions If not adjust the front panel GAIN for exactly four divisions of deflection The GAIN adiustment is engaged by pressing in the GAIN
88. ation in your order Part number instrument type or number serial number and modification number if applicable part 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 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 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 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 ihe 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 at
89. ayed The network C246 C345 C245 R246 R345 R245 pro vides high frequency compensation R245 C245 in this net work provide high frequency response adjustment for this stage Emitter Follower Emitter Follower stage Q260 Q360 provides a low output impedance to drive the Signal and Trigger Channel Switch es U270 U470 This stage also provides isolation between the Second Cascode Amplifier and U270 U470 CHANNEL 2 INPUT AMPLIFIER General The Channel 2 Input Amplifier circuit is basically the same as the Channel 1 Input Amplifier circuit Only the dif ferences between the two circuits are described here Por tions of this circuit not described in the following description operate in the same manner as for the Channel 1 Input Am plifier circuit corresponding circuit numbers assigned in the 400 599 range Fig 3 2 shows a detailed block diagram of the Channel 2 Input Amplifier circuit A schematic of this circuit is shown on Diagram 3 in the Diagrams section Paraphase Cascode Amplifier The Paraphase Cascode Amplifier for Channel 2 consists of Q420 Q520 Q425 Q525 Q426 and Q526 In addition to the functions described under Channel 1 Input Amplifier the Channel 2 Paraphase Cascode Amplifier stage provides 3 3 Circuit Description 7A18A PARAPHASE INPUT CASCODE SOURCE AMPLIFIER FOLLOWER GAIN BON 0520 0426 N AND atten 104108 Q425 052 VARIABLE DC Sa BAL CH 2 POLARITY
90. bleshooting the 7A18A The Schematic Diagrams Circuit Description and Calibration sections should be used to full advantage The Circuit Description section gives detailed information on circuit behavior and output requirements Troubishooting Aids Diagrams Circuit diagrams are given on foldout pages in Section 8 The circuit number and electrical value of each component in this instrument are shown on the diagrams important voitages are also shown Circuit Board The circuit board used in the 7A18A is outlined on the schematic diagrams and a illustration of the board is shown on the back of Diagram 1 Each board mounted electrical component is identified on the illustration by its circuit number Component and Wiring Color Code Colored stripes or dots on resistors and capacitors signify electrical values tolerances etc according to the EIA standard color code Components not color coded usually have the value printed on the body E__FAIRA 2154 15 115 The insulated wires used for interconnection in the are color coded to facilitate tracing a wire from one point to another in the unit Semiconductor Lead Configuration Figure 5 1 shows the lead configuration of the semiconductor devices used in this instrument Troubleshooting Equipment The following equipment is useful for troubleshooting the 7A18A 1 Semiconductor Tester Some means of testing the transistors
91. cal Parts 7A18A Name amp Description TRANSISTOR SILICON NPN TRANSISTOR SILICON PNP SEMICOND SE SELECTED TRANSISTOR SILICON NPN SEMICOND SE SILICON PNP SEMICOND DVC SE SILICON FET PAIR SEMICOND SE SILICON PNP TRANSISTOR SILICON NPN TRANSISTOR SILICON PNP TRANSISTOR SILICON FE DUAL SEMICOND SE SELECTED SEMICOND DVG SE SILICON NPN SEMICOND DVC SE SILICON NPN SEMICOND DVC SE SILICON PNP SEMICOND DVC SE SILICON FET PAIR SEMICOND DVC SE SILICON PNP TRANSISTOR SILICON NPN TRANSISTOR SILICON PNP SEMICOND DVC SE SELECTED SEMICOND DVC SE SILICON NPN SEMICOND SE SILICON NPN SEMICOND DVC SE SILICON PNP SEMICOND DVC SE SILICON FET PAIR SEMICOND DVC SE SILICON PNP TRANSISTOR SILICON NPN TRANSISTOR SILICON PNP RES FXD CMPSN 470K 0HM 10 0 23W RES FXD CMPSN 47 5 0 25 RES FXD CMPSN 560 OHM 576 0 25W RES FXD CMPSN 390 OHM 5 0 25W RES FXD CMPSN 910 OHM 5 0 25W RES FXD FILM 21 OHM 1 0 125W RES FXD FILM 383 OHM 1 0 125W RES FXD FlLM 4 64K OHM 1 0 50W RES FXD FILM 21 OHM 1 0 125W RES FXD CMPSN 620 OHM 5 0 25W RES FXD FiLM 182 1 0 125 RES FXD CMPSN 560 OHM 5 0 25W RES FXD CMPSN 2 4K 5 0 25 RES FXD FILM 49 9K OHM 1 0 125W RES FXD CMPSN 220 OHM 5 0 25W RES FXD FILM 49 9 OHM 1 0 125W 4 42 OHM 1 0 50W RES FXD FILM 200 OHM 1 0 125W RES VAR NONWIR TRMR 500 OHM 0 5W RES FXD
92. ch it was il tustrated the lookup table will list the diagram number of other diagrams that the circuitry of the circuit board appears on D Modified Component 7 Depicted in Grey or With Grey Outline See Parts List Strap or Link Plug to Board Box identifies ntrois Connectors and indicators Coaxial connectors male 7 female Plug Index signifies pin No 1 Ds External Screwdriver Adj Shielding Selected value see Parts List and Maintenance Section for Selection Criteria nennen Decoupled or Filtered Voltage eine een OTOL to Diagram Number E SMS EE Schematic Name and Number WURST VOLTAGE AND WAVEFORM TEST CONDITIONS voltage measurements were obtained under the following conditions unless noted otherwise on the indi vidual diagrams Voltmeter Type Non loading digital multimeter Input impedance Range 0 1000 volts Recommended type Tektronix 7D13A as used for voltages Digital Multimeter on diagrams 7A18A left vertical compartment DISPLAY MODE ALT TRIGGER SOURCE MODE CH 2 POLARITY CH CH 2 VOLTS DIV 10 mV COUPLING DE POSITION Centered VARIABLE CAL IN Signal Applied No signal for voltage meas urements 40 mV square wave from oscil loscope Calibrator applied to both connectors for forms 7A16A right vertical compartment using a 10X probe with readout coding r
93. d For example in Fig 2 3 the mea surement is between the reference line and point A 2 int A 4 Vertical tt Distance Fig 2 3 Measuring instantaneous voltage with respect to some reference 8 Establish the polarity of the waveform With the CH 2 POLARITY switch in the UP position any point above the reference line is positive 9 Multiply the distance measured in step 7 by the VOLTS DIV setting Include the attenuation factor of the probe if used EXAMPLE Assume the vertical distance measured is 3 6 divisions see Fig 2 3 and the waveform is above the reference line using a 10X probe with a VOLTS DIV setting of 0 5 V Using the formula Instan vertical VOLTS probe taneous distance X polarity X DIV X attenuation Voltage divisions setting factor Substituting the given values Instantaneous 3 6 X 1X0 5V X 10 Voltage The instantaneous voltage is 18 V 2 5 Operating Instructions 7A18A Comparison Measurements some applications it may be desirable to establish arbi trary units of measurement other than those indicated by the VOLTS DIV switch This is particularly useful when com paring unknown signals to a reference amplitude One use for the comparison measurement technique is to facilitate calibration of equipment where the desired amplitude does not produce an
94. dure nen Sac ERES G ae 4 9 Electrode configuration for semiconductors used in this instrument 5 2 Option 0B 6 1 Side view of 7A18A Option 06 63 Rear view of A2 Amplifier board for either Option 06 or standard 7A18A 6 3 8 1 and 8 2 are of circuit board assemblies and in the diagrams section AIDA OPERATORS SAFETY SUMMARY The general safety information in this part of the summa ry is for both operating and servicing personnel Specific warnings and cautions wili be found throughout the manual where they apply but may not appear in the summary Terms in This Manual CAUTION statements identify conditions or practices that could result in damage to the equipment or other property WARNING statements identify conditions or practices that could result in personal injury or loss of life Terms as Marked on Equipment CAUTION indicates a personal injury hazard not immedi ately accessible as one reads the marking or a hazard to property including the equipment itself _ DANGER indicates a personal injury hazard immediately accessible as one reads the marking Symbols in This Manual Symbols As Marked On Equipment This symbol indicates where applicable cautionary or other information is to be found DANGER High voltage Power Source Protective ground earth terminal ATTENTION refer to manual This product is i
95. e gerh Seve 19124 caved 879 979 JOGUINN 1042907 pierog uone2o peog E gt 2 HO div 2 TANNVHO uoneoo ASSV ZV Old WELW 2 WAVEFUMMS FUR Hire ead sce be eR i hen E HUA A AAA BA ESTAS AAA ARA IATA IX oi 6 WAL lt gt CL 1 91 LAdNI 7 321 woe TN 091999390 SidVd dO BAIPSURS 25935 JUAN Aquasseqn agewegog Y 9V HUNAN 935 GNY 5 DES 4511 28 gt gt a uojoag eoueusjurew 995 1204393 pua 85 Agwassy DU SPUSUOGUIOD 23310 51538 jr SIQUUAN 82 Agusassy 76219 CV m neo dagny 119409107 1430440 9861 TASI Ati N 39 o 6x 01956
96. e five millivolts the attenuators are switched into the circuit singly or in pairs to produce the deflection factor indicated on the front panel These attenu ators are frequency compensated voltage dividers For dc and low frequency signals the attenuators are primarily re sistance dividers and the voltage attenuation is determined by the resistance ratio in the circuit The reactance of the capacitors in the circuit is so high at low frequencies that their effect is negligible However at higher frequencies the reactance of the capacitors decreases and the attenuator becomes primarily a capacitance divider In addition to providing constant attenuation at all fre quencies within the bandwidth of the instrument the input attenuators are designed to maintain the same input RC characteristics one megohm X 20 pF for each setting of the VOLTS DIV switch Each attenuator contains an adjustable series capacitor to provide correct attenuation at high fre quencies and an adjustable shunt capacitor to provide cor rect input capacitance PARAPHASE CASCODE AMPLIFIER INPUT SOURCE FOLLOWER GAIN AND VARIABLE CONTROLS IDENTIFY CHANNEL 1 INPUT AMPLIFIER General The Channel 1 Input Amplifier converts the single ended signal applied to the Channel 1 input connector to differen tial push pull output Fig 3 1 shows a detailed block dia gram of the Channel 1 Input Amplifier A schematic of this circuit is shown on Diagra
97. flow can occur in Q345 depending upon the instantaneous polarity of push pull signals When S667 is in the variable position circuit operation is the same except R663 is used to select the gain of the amplifier The gain position has approximately a 1 5 to 1 range whereas the variable has a 3 0 to 1 range Channel 2 works in an identical manner with Q445 and 0545 in place Q245 0345 Circuit Description 7A 18A Second Cascode Amplifier The Second Cascode Amplifier stage provides a signal gain of approximately two This stage includes the POSI TION control and the trace IDENTIFY circuit The emitters of common base connected Q250 Q350 provide a low im pedance point for iniection of the POSITION control and IDENTIFY switch currents Position of the trace is deter mined by the setting of the POSITION control R11 This control changes the current drive to Q250 0350 Since the emitters are a very low impedance point in the circuit there is negligible voltage change at these points However the change in current from the POSITION control produces resultant dc voltage difference at the collectors to change the position of the trace Trace identification is accom plished by inserting resistor R357 from ground through CR256 to the junction of R11 R256 This results in a slight increase in the emitter current of Q250 to cause the trace to move This aids in identifying the channel 1 trace when mui tiple traces are displ
98. g position when varying the VARIABLE controls The front panel gain adjustment and the variable gain control circuits consists of Q245 Q345 U675 and associ ated components Q345 acts as a resistor with its value determined by the position of the wiper of R663 or R668 Since Q345 is in parallel with R242 and R342 it shunts part of the signal current away from the common base stages of Q250 and Q350 thereby reducing the gain of the amplifier When S667 is in the calibrated position the wiper volt age of R668 is applied to the non inverting input of U675B U675B controls the resistance of 0245 so that the junction of R677 and R681 is equal to the voltage selected by the wiper of 8668 U675B and Q245 sets the potential across R676 and R677 equal to the divider action of R665 and R666 along with the divider action of R668 Since R676 R677 approximate the emitter impedence of i 0250 0350 and the gates of Q345 0245 are common the resistance of Q345 will equal the resistance of Q245 and thus shunt a proportional amount of signal current equal to the ratio of R681 s current flowing in Q245 away from the signal path U675A holds the junction of R676 R677 at the common mode voltage level of the drain and source of Q345 Since equal currents flow in R676 R677 and their junction is tied to the common mode point the push pull condition at the drain and source of Q345 is simulated Either source to drain or drain to source current
99. he sig nal is coupled to the amplifier in put while the DC component is blocked GND Grounds the amplifier input while maintaining the same load for the input signal Provides a charge path for the AC coupling capacitor to precharge the input circuit before switching the input to AC VARIABLE INT VOLTS DIV 4329 02 Fig 2 1 Front panel controls and connectors 7A18A shown DC Both AC and DC components of the signal are coupled to the amplifier input POSITION Controls position of the trace Posi tioning of the trace in the ADD Display Mode is controlled by CH 1 POSITION control only IDENTIFY Deflects trace about 0 3 division for trace identification In instruments with readout also replaces readout with the word IDENTIFY 2 1 Cantina VOLTS DIV Selects calibrated deflection factors from 5 mv Div to 5 V Div ten steps in a 1 2 5 sequence VARIABLE VOLTS DIV Provides continuously variable uncalibrated settings between cali brated steps Extends the deflection factor range to 12 5 V Div or more GAIN Adjustment When the VARIABLE control is pushed in it becomes a front panel screw driver adjustment for calibra tion of deflection factor DISPLAY MODE Selects one of the following modes of operation 1 singie trace display of the signal applied to Channel 1 dual trace display of the signal applied to both channels The chan
100. he square wave generator high amplitude output to the CH 1 Input connector with the 42 inch cable 10X BNC attenuator in line 50 ohm GR termination and 20 pF normalizer 4 9 Calibration 7A18A d Set the square wave generator for six division dis play 30 millivolts of a one kilohertz signal e Set the time base unit for a triggered display at a sweep rate of 2 millisecond division f CHECK CRT display for square wave with square corner 9 ADJUST Channel 1 C100 for optimum square cor ner on the displayed waveform use tuning tool See Fig 4 1 for adjsutment location h Disconnect the normalizer from the CH 1 input con nector and connect it to the CH 2 input connector i Set the DISPLAY MODE switch to CH 2 display for square wave with square corner ADJUST Channel 1 C100 for optimum square cor ner on the displayed waveform See Fig 4 1 for adjustment locations Disconnect all test equipment m Remove the 7A18A and plug in extender from the Indicator Oscilloscope Install the 7A18A only in the left ver tical compartment 4 Adjust Attenuator Compensation a Connect the square wave generator high amplitude output to the CH 2 input connector with the 42 inch BNC cable 10X BNC attenuator in line 50 ohm BNC termination and 20 pF normalizer b Set the CH 1 and CH2 VOLTS DIV switches to 10 mV Set the square wave generator for a six division dis play
101. ibration of the 7A18A every 1000 hours of operation or every six months if used infrequentiy Before complete calibration thoroughly clean and inspect this instrument as outlined in the Maintenance section Tektronix Field Service Tektronix inc provides complete instrument repair and recalibration at local Field Service Centers and the Factory Service Center Contact your local Tektronix Field Office or representative for further information Using This Procedure General This section provides several features to facili tate checking or adjusting the 7A18A These are index To aid in locating a step in the Performance _ Check or Adjustment procedure an index is given preceding Part I Performance Check and Part Il Adjustment procedure Performance Check The performance of this instru ment can be checked without removing the side shields or making internal adjustments by performing only Part I Per formance Check This procedure checks the instrument against the tolerances listed in the Performance Require ment coiumn of Section 1 In addition a cross reference is provided to the step in Part lI Adjustment which will return the instrument to correct calibration In most cases the ad justment step can be performed without changing control settings or equipment connections Adjustment Procedure To return this instrument to cor rect calibration with the minimum number of steps perform only Part li Adjustment
102. ing P6053B probe used for waveforms on diagrams Polarity Bandwidth Full Position Centered Coupling AC Variable Cal in TAIRA 7880 A Horizontal compartment Level Slope Centered on positive slope Triggering Mode P P Auto Coupling AC Source Ext Magnifier X1 Time Div 1ms Variable Cal In Ext Trig In connector No connection for voltage measurements For waveforms Sig Out from oscilloscope connected to Ext Trig In connec tor 7704A Vertical Mode Right Horizontal Mode A Intensity Optimum B Intensity Counterclockwise Calibrator Volts 40 Rate 1 kHz A Trigger Source Right Vert B Trigger Source Left Vert voltages given on the diagrams are in volts currents are in milliamps Waveforms shown are actual waveform photographs taken with a Tektronix Oscilloscope Camera System Vertical deflection factor shown on waveform is the actual deflection factor from the probe tip Voltages and waveforms on the diagrams shown in grey not absolute and may vary between instruments because of component tolerances internal calibration or front panel settings Readouts are simulated in larger than normal type NOTE The spring tension of the Din sockets ensures a good connection between the circuit board and pin This spring tens on may be damaged by using the pin Sockets as a connecting point for spring loaded probe tips alligator clips etc gt VSIVL
103. ipment is required to completely check and adjust this instrument However some of the items used only for the Performance Check can be deleted with out compromising the instrument s measurement capabili ties For example the low frequency constant amplitude signal generator is used only in the Performance Check and may be deleted if the user does not desire to check the lower frequency response or trigger source operation Equipment used only for the Performance Check procedure is indicated by note 1 items required only for the Adjust ment procedure are indicated by note 2 Calibration 7A18A Table 4 1 77 Test Equipment u Example of Applicable Description Minimum Specifications Purpose Test Equipment Oscilloscope mainframe 7000 Series with 2 TEKTRONIX 7603 horizontal plug in compartments Oscilloscope bandwidth 75 MHz Time Base plug in unit TEKTRONIX 7B Series sweep unit Provides horizontal sweep TEKTRONIX 7B50A for oscilioscope system Time Base Amplitude calibrator Output signal 1 kHz square wave Vertical gain checks and TEKTRONIX PG 506 amplitude 20 mV to 20 V accuracy adjustments Pulse Generator within 0 2596 Medium frequency Frequency 50 to 75 MHz output Common mode rejection TEKTRONIX SG 503 sine wave generator amplitude 50 mV to 200 mV into 50 2 and bandwidth checks Signal Generator Provides a display for unit under test Low frequency signal
104. ith a discussion of the instrument using the block diagram shown in the Diagrams section Then each circuit is described in detail using block diagrams to show the interconnections between stages in each major circuit and the relationship of the front panel controls to the individual stages Complete schematics of each circuit are given in the Dia grams section Refer to these schematics throughout the following circuit description for electrical values and relationship BLOCK DIAGRAM The following discussion is provided to aid in understand ing the overall concept of the 7A18A before the individual circuits are discussed in detail Only the basic interconnec tions between the individual blocks are shown on the block diagram see Diagrams section Each block represents major circuit within the instrument The number on each block refers to the schematic on which the complete circuit is found The signal to be displayed on the crt is applied to the input connector The signal passes through the Input Cou pling switch where the appropriate coupling is selected to the attenuators The VOLTS DIV switch selects the correct amount of attenuation and the signal is passed to the input amplifier The Channel 1 Input Amplifier circuit provides gain set ting variable gain control and trace positioning The Chan nel 2 Input Amplifier provides signal polarity inversion in addition to gain setting variable gain control and trace
105. l 1 and 2 Upper Bandwidth 4 5 6 Check Channel 1 and 2 Lower Frequency pc cag ANS dus 4 6 7 Check Channel Isolation 4 6 8 Check Common Mode Rejection Ratio 4 6 4 4 index to Part I Performance Check cont Page 9 Check Alternate Operation 4 7 10 Check Chopped Operation 4 7 11 Check Trigger Source Operation 4 7 Preliminary Procedure for Performance Check NOTE The performance of this instrument can be checked at any temperature within the 0 C to 50 C range unless stated otherwise 1 Install the ZABA in the left vertical compartment of the indicator Oscilloscope plug in 2 Connect the Indicator Oscilloscope to a power source which meets the frequency and voltage requirements of the oscilloscope power supply 3 Turn the indicator Oscilloscope power Allow at least twenty minutes warmup for checking the 7A18A to the given accuracy 4 Set the controls as given under Preliminary Control Settings The checks titled Channel 1 and 2 apply equally to both channels Perform the check on the channel selected by the DISPLAY MODE switch 1 Check Channel 1 and 2 GAIN a Connect the standard amplitude calibrator output to the CH 1 and CH 2 input connectors with the 42 inch BNC cable and dual input coupler b Set the standard amplitude calibrator for a 50 millivoit square
106. larity 7 Adjust the Channel 2 VOLTS DIV switch and VARI ABLE control for maximum cancellation of the common mode signal The signal which remains should be only the desired portion of the Channel 1 signal EXAMPLE An example of this mode of operation is shown in Fig 2 6 The signal applied to Channel 1 contains unwanted line frequency components Fig 2 6A A corre sponding line frequency signal is connected to Channel 2 Fig 2 6B Fig 2 6C shows the desired portion of the signal as displayed when common mode rejection is used 2 8 po A Channel 1 Signal Resultant Display 1126 44 Fig 2 6 Using the ADD mode for common mode rejection Channel 1 signal contains desired information along with line frequency component B Channel 2 contains line frequency Ed only C Resultant CRT display using common mode rejection gt 5 SOTO lt BER 2 SESSIONS VRR LISTER 555070 255 252 569555 NS EX X 2 8305 2 2 gt 5 S 255 22 5520 50 5222 EN xS 22922 55 ES 22 06 559 TAN S ES 5 255 EN 5 x 55 25 K amp 255 N NAS IE ER NR A AN PR 20 R 2 2 22 2225552 525525550 RESTE XS 255 22 225
107. lowing information 1 Instrument type 7A18A 2 Instrument Serial Number 3 A description of the part if electrical include the cir cuit number 4 Tektronix Part Number Soldering Techniques Attenuator Circuit Boards The Attenuator circuit boards are made from polyphenylene oxide because of its excellent electrical characteristics Use more than normal care when cleaning or soldering this material The following rules should be observed when removing or replacing parts 1 Use a very smali soldering iron not over 15 watts 2 Do not apply more heat or apply heat for a longer time than is absolutely necessary 3 Use a vacuum type desoldering tool to remove the excess solder from the circuit board 4 Do not apply any solvent containing ketones esters or halogenated hydrocarbons 5 To clean use only water soluble detergents ethyl methyl or isopropyl alcohol COMPONENT REPLACEMENT General The exploded view drawing associated with the Mechan ical Parts List may be helpful when disassembling or reas sembling individual components or sub assemblies Circuit Board Removal In general the circuit boards used in the 7A18A need never be removed unless they must be replaced Electrical connections to the boards are made by soldered connec tions If it is necessary to replace a circuit board assembly use the following procedures A READOUT CIRCUIT BOARD REMOVAL 1 Disconnect the wires connected to the
108. m Test Voltage 777 Heat Sink Board P O Part of circuit board Assembly Number 7 678 A Y COMPONENT HURBER EXAMPLE Component Number 23 duemby _ Tektronix Part _ for circuit boards Qf used Components save ot Assey Number eh 5 en al Sepiaceates Paris isst The information and special symbols below may appear in this manual SYNC GENERATOR Y14 15 1966 Y14 2 1973 Y 10 5 1968 Drafting Practices Line Conventions and Lettering Letter Symbols for Quantities Used in Electrical Science and Electrical Engineering American National Standard Institute 1430 Broadway New York New York 10018 Component Values 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 microfarads uF Resistors Ohms 0 The schematic diagram and circuit board component location iliustration have grids A lookup table with the grid coordinates is provided for ease of locating the component Only the components illustrated on the facing diagram are listed in the lookup table When more than one schematic diagram is used to illustrate the circuitry on a circuit board the circuit board illustration may only appear opposite the first diagram on whi
109. m 2 in the Diagrams section input Source Follower The Input Source Follower Q210A provides a high input impedance with a low impedance drive for the following stage R210 limits the current drive to the gate of Q210A Dual diode CR210 provides circuit protection by limiting the voltage swing at the gate Q210A Dual diode CR210 vides circuit protection by limiting the voltage swing at the gate of Q210A to about 15 volts Q210B provides a con stant current source for Q210A Q210A and Q210B are en capsulated in the same case so that Q210B temp erature compensates the circuit Paraphase Cascode Amplifier Paraphase amplifier Q220 Q320 in conjunction with 0225 0325 forms a cascode amplifier Q220 Q320 convert SECOND CASCODE AMPLIFIER EMITTER FOLLOWER TO SIGNAL CHANNEL SWITCH U270 TO TRIGGER CHANNEL SWITCH FROM 09470 513 1126 08 4329 20 Fig 3 1 Channel 1 Input Amplifier detailed block diagram Circuit Description 7A18A the single ended input signal to differential output signal Diodes CR220 CR221 hold the voltage level at the base of Q220 close to ground to limit the voltage swing to about 0 6 voit Common base connected Q225 Q325 provide isolation between the paraphase amplifier and the GAIN controis Adjustment R321 varies the base level of Q320 to provide the same voltage levels at the collectors of Q225 and 0325 This prevents a zero volt reference trace from changin
110. n of the DISPLAY MODE switch is shown in Figure 3 3 TRIGGER SOURCE Switch The TRIGGER SOURCE switch provides logic level out puts to the Trigger Channel Switch U470 Channel Switch es Diagram 4 A table of the outputs for each switch position is shown in Figure 3 4 Circuit Description 7A18A CONNECTORS AND READOUT Connectors All the connections made to the mainframe by the 7A18A are shown on the Connectors schematic Diagram 6 Also shown are the power supply decoupling components Readout Encoding The Readout Encoding circuit consists of switching resis tors and probe sensing stage Q620 and is shown on Dia gram 5 This circuit encodes the Channel 1 and 2 Row and Column output lines for readout of deflection factor uncalibrated deflection factor VARIABLE information and signal inversion Channel 2 only Data is encoded on these output lines by switching resistors between them and the time siot input lines or by adding current through Q620 R647 CR647 are switched between time slot three TS 3 and Column output line when the CAL IN switch is in the uncal position This results in the symbol gt greater than being displayed preceding the deflection factor readout R648 Channel 2 only is switched between TS 2 and the Column output line when the CH 2 POLARITY switch is in the INVERT position This results in the symbol 1 inverted being displayed preceding the deflection factor readout Switching resistors
111. nels are alternately dis played and switching occurs at the end of each time base sweep ADD Algebraically adds the sig nals applied to the and CH 2 input connectors and the algebraic sum is displayed on the CRT The CH2 POLARITY switch allows the display to be CH 1 CH2 or CH1 CH2 Position of the trace in this dis play mode is controlled by a CH 1 POSITION control only CHOP A dual trace display of the signals applied to both channels The two channels time share the sweep as determined by the indi cator oscilloscope CH 2 single trace display of the signal applied to CH 2 TRIGGER SOURCE Selects source of the trigger signal The trigger signals provide internal triggering for the oscilloscope time base units CH 1 Internal triggering signal ob tained from signal applied to CH 1 MODE Internal trigger signal automatically follows DISPLAY MODE selection In ADD or CHOP display modes the trigger 2 2 Operating Instructions 7A18A signal is the algebraic sum of CH 1 and CH 2 trigger CH 2 Internal trigger signal ob tained from signal applied to CH2 CH 2 POLARITY Provides means of inverting the CH 2 display UP A positive going signal at the CH 2 input connector de flects the CRT display upward INVERT A positive going signal at the CH 2 input connector de flects the CRT display downward GENERAL OPERATING INFORMATION introduction For single trace oper
112. ng control settings DISPLAY MODE CH 2 CH 1 VOLTS DIV 10 mV e display for 0 4 division or less deflection channel isolation display ratio 50 1 or better f Disconnect the termination from Channel 1 and con gt nect it to the 2 input connector pd g Set the CH 2 VOLTS DIV switch to 1 h Set the generator for a two division display 200 milli volts at 50 megahertz Change the following control settings CH 1 VOLTS DIV 10 mV DISPLAY MODE CH 1 CH 2 VOLTS DIV 10 mV CHECK Crt display for 0 4 division or less deflection Disconnect test equipment 8 Check Common Mode Rejection Ratio a Change the following control settings CH 1 and CH 2 VOLTS DIV 10 mV b Connect the medium frequency generator to the CH 1 and CH 2 input connectors with the 42 inch BNC cable in 7 line 50 BNC termination and the dual input coupler REV JUN 1983 Set the constant amplitude generator for eight divi Sion display 80 millivolts at 50 megahertz d Change the following control settings DISPLAY MODE ADD CH 2 POLARITY INVERT e CHECK Ort display for 0 8 division or less deflection common mode rejection ratio 10 1 or better f Disconnect all test equipment 9 Check Alternate Opreation a Set the DISPLAY MODE switch to ALT b Position the trace about two divisions apart C furn the time base unit time division switch
113. nstrument is to be shipped to a Tektronix Service Center for service or repair attach a tag showing owner with address and the name of an individ ual at your firm that can be contacted complete instrument serial number and a description of the service required Save and re use the package in which your instrument was shipped If the original packaging is unfit for use or not avaitable repackage the instrument as follows Surround the instrument with polyethylene sheeting to protect the finish of the instrument Obtain a carton of corrugated cardboard of the correct carton strength and having inside dimensions of no less than six inches more than the instrument dimensions Cushion the instrument by tightly packing three inches of dunnage or urethane foam between carton and instrument on all sides Seal carton with shipping tape or industrial stapler The carton test strength for your instrument is 200 pounds Selected Component Criteria During initial calibration selected values of the following components may have been installed to meet certain perfor mance requirements for this instrument If during recalibration following corrective maintenance or hours of service performance checks it is determined that one or more of these components needs replacement the following criteria Table 5 1 should be used Table 5 1 Selected Component Criteria Circuit Involved Range of Values Criteria Effects 0
114. ntended to operate from a power source that will not apply more than 250 volts rms between the supply conductors or between either supply conductor and ground A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation Grounding the Product This product is grounded through the grounding conduc tor of the power cord To avoid electrical shock plug the power cord into a properly wired receptacle before connect ing to the product input or output terminals A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation Danger Arising From Loss Of Ground Upon loss of the protective ground connection all acces sible conductive parts including knobs and controls that may appear to be insulating can render an electric shock Use The Proper Power Cord Use only the power cord and connector specified for your product Use only a power cord that is in good condition Refer cord and connector changes to qualified service personnel Use The Proper Fuse To avoid fire hazard use only the fuse of correct type voltage rating and current rating as specified in the parts list for your product Refer fuse replacement to qualified service personnel Do Not Operate in Explosive Atmospheres To avoid explosion do not operate this product in an explosive atmosphere unless it has been specifically certi fied for such operati
115. omponents in the Components which are soldered in place are best checked by disconnecting one end to isolate the measure ment from the effects of surrounding circuitry TRANSISTORS AND INTEGRATED CIRCUITS The best check of transistor and integrated circuit operation is actual performance under operating conditions If a transis tor or integrated circuit is suspected of being defective it can best be checked by substituting a component known to be good however be sure that circuit conditions are not such that a replacement might also be damaged If substi tute transistors are not available use a dynamic tester such as TEKTRONIX 576 Static type testers may be used but since they do not check operation under simulated operat ing conditions some defects may go unnoticed Figure 5 1 shows base pin and socket arrangements of semiconductor devices Be sure the power is off before attempting to re move or replace any transistor or integrated circuit Integrated circuits can be checked with a voltmeter test oscilloscope or by direct substitution A good understand ng of the circuit description is essential to troubleshooting Maintenance circuits using integrated circuits Use care when checking voltages and waveforms around the integrated circuits so that adjacent leads are not shorted together An integrated circuit test clip provides a convenient means of clipping a test probe to the 14 and 16 pin integ
116. on eee TAAGA TRIA SERVICE SAFETY SUMMARY FOR QUALIFIED SERVICE PERSONNEL ONLY Refer also to the preceding Operators Safety Summary Do Not Service Alone Do not perform intenal service or adjustment of this prod uct unless another person capable of rendering first aid and resuscitation is present Use Care When Servicing With Power On Dangerous voltages exist at several points in this prod uct To avoid personal injury do not touch exposed connec tions and components while power is on Disconnect power before removing protective panels soldering or replacing components Power Source This product is intended to operate from a power source that will not apply more than 250 volts rms between the supply conductors or between either supply conductor and ground A protective ground connection by way of the grounding coductor in the power cord is essential for safe operation E N e 7A18A Dual Trace Amplifier TAISA Section 1 7A18A SPECIFICATION Introduction The 7A18A Dual Trace Amplifier plug in unit is designed for use with TEKTRONIX 7000 Series Oscilloscopes The 7A18A is a dual channel medium bandwidth amplifi er internal gain and compensation circuits are automatically switched to correspond to the setting of the VOLTS DIV switch Channel 2 can be inverted for differential measure ments The
117. only for Adjustment Procedure 3Requires TM 500 Series Power Module Purpose Example of Applicable Test Equipment Used for potentiometer adjustments Used for variable capacitor adjustments Used for capacitance and attenuator adjustments Xcelite R 3323 Tektronix Part Number 003 0000 00 Tektronix Part Numbers 003 0307 00 003 0334 00 and PEN 003 0497 00 4 3 Calibration 7A18A vaubration 7 A18A PART I PERFORMANCE CHECK introduction The following procedure checks the performance of the 7A18A without removing the covers or making internal ad justments tolerances given in this procedure are based on Section 1 of this manual Preliminary Control Settings Set the Indicator Oscilloscope and 7A18A controls as follows for both Performance Check and Adjustment procedure indicator Oscilloscope Intensity Midrange Focus Adjust for well defined display Graticule As desired Calibrator 40 mV Rate 1 kHz Vert Mode Left Trig Source Left Vert 7A18A DISPLAY MODE CH 1 TRIGGER SOURCE MODE CH 2 POLARITY UP CH 1 and CH 2 POSITION Midrange VOLTS DIV 10 mV AC GND DC DC Index to Part Check EN Page 1 Check Channel 1 and 2 GAIN 4 4 2 Check Channel 1 and 2 Deflection Factor accro M TI 4 5 3 Check Channel 1 and 2 VARIABLE VOLTS DIV RANGO EE 4 5 4 Check Channel 1 and 2 Trace IDENTIFY 4 5 5 Check Channe
118. rated circuits This device also doubles as an integrated circuit extraction tool B DIODES A diode can be checked for an open or for a short circuit by measuring the resistance between terminals with an ohmmeter set to the X 1k scale The diode resis tance should be very high in one direction and very low when the meter leads are reversed Do not check tunnel diodes or back diodes with an ohmmeter CAUTION Do not use an ohmmeter scale that has a high internal current High currents may damage the diodes C RESISTORS Check resistors with an ohmmeter Re sistor tolerance is given in the Electrical Parts List Resis tors normally do not need to be replaced unless the measured value varies widely from the specified value D CAPACITORS A leaky or shorted capacitor can be detected by checking resistance with an ohmmeter on the highest scale Use an ohmmeter which will not exceed the voltage rating of the capacitor The resistance rating should be high after initial charge of the capacitor An open capaci tor can best be detected with a capacitance meter or by checking whether the capacitor passes AC signals 7 Repair and Readjust the Circuit Special techniques required to replace components in this unit are given under Component Replacement Be sure to check the perfor mance of any circuit that has been repaired or that has had any electrical components replaced Recalibration of the af fected circuit may be necessary RE
119. roduction The following procedure returns the 7A18A to correct calibration All limits and tolerances given in this procedure are calibration guides and should not be interpreted as in strument specifications except as listed in the Performance Requirement column of Section 1 The actual operation of the instrument may exceed the given limits or tolerances if the instrument meets the Performance Requirements as checked in Part I Performance Check of this section index to Part li Adjustment Page 1 Adjust Channel 1 and 2 Dc Balance 4 8 2 Adjust Channel 1 and 2 4 9 3 Adjust Channel 1 and 2 Input Capacitance 4 9 4 Adjust Channel 1 and 2 Attenuator Compensation 4 10 5 Adjust Channel 1 and 2 High Frequency Compensation 4 11 Preliminary Procedure For Adjustment NOTE This instrument should be adjusted at an ambient temperature of 25 C 5 for best overall accuracy 1 Remove the left side shield from the 7 and the left side panel from the Indicator Oscilloscope 2 Install the 7A18A in the left vertical plug in compart ment of the Indicator Oscilloscope 3 Connect the Indicator Oscilloscope to a power source which meets the frequency and voltage requirements of the oscilloscope power supply 4 Turn the Indicator Oscilloscope power on Allow at least twenty minutes warmup before proceeding 5 Set the controls as given under Prelimin
120. round reference at the input of the amplifier without externally grounding the input connectors However the signals connected to the inputs are not grounded and the same DC load is presented to the signal source VOLTS DIV and VARIABLE Controls The amount of vertical deflection produced by a signal is determined by the signal amplitude the attenuation factor of the probe the setting of the VOLTS DIV switch and the setting of the VARIABLE control Calibration deflection fac tors indicated by the settings of the VOLTS DIV switch ap ply only when the VARIABLE control is in the calibrated CAL IN position The VARIABLE control provides variable uncalibrated settings between the calibrated steps of the VOLTS DIV switch With the VARIABLE control fully counterclockwise and the VOLTS DIV set to 5 volts div the uncalibrated verti cal deflection factor is extended to at least 12 5 volts division By applying a calibrated voltage source to the input connector any specific deflection factor can be set within the range of the VARIABLE control Operating Instructions 7A18A CH 2 POLARITY Switch The CH 2 POLARITY switch may be used to invert the displayed waveform of the signal applied to the CH 2 input This is particularly useful in added operation of the 7A18A when differential measurements are to be made The CH 2 POLARITY switch has two positions UP and INVERT In the UP position the displayed waveform will have the s
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122. s coupled directly to the Input At tenuator stage In the AC position the input signal passes through capacitor C10 This capacitor prevents the DC component of the signal from passing to the amplifier The GND position opens the signal path and connects the input circuit of the amplifier to ground This provides a ground reference without the need to disconnect the applied signal from the input connector Resistor R102 connected across the AC GND DC switch aliows C10 to be precharged in the GND position so the trace remains on screen when switch ing to the AC position if the applied signal has a high DC level input Attenuator The effective overall deflection factor of the 7 is de termined by the setting of the VOLTS DIV switch S200A The basic deflection factor is five millivolts per division of crt deflection To increase the basic deflection factor to the val ues indicated on the front panel precision attenuators are switched into the circuit These attenuators are hybrid de vices which contain the necessary resistances and capaci 3 1 2 7 IRA tors Each attenuator is replaceable as a unit 5200A is a cam type switch and the dots on the contact closure chart see Diagram 1 indicate when the associated contacts are in the position shown open or closed In the 5 mV Div posi tion input attenuation is not used the input is con nected directiy to the input amplifier For switch positions abov
123. s plug in compartments Weight av2 Pounds 10 Ounces 1 4 kilograms SPS IIT 77 85 Fh SMS OPERATING INSTRUCTIONS To effectively use the 7 the operation and capabili ties of the instrument must be known This section de scribes front panel control functions general information on signal input connections and other subjects that pertain to various measurement applications Installation The 7A18A is calibrated and ready for use as received can be installed in any compartment of Tektronix 7000 5 ries oscilloscopes but is intended for principal use in vertical plug in compartments To install align the upper and lower rails of the 7A18A with the oscilloscope tracks and fully in sert it The front will be flush with the front of the oscillo scope when the 7 is fully inserted and the latch at the bottom left corner of the 7 will be in place against the front panel remove the 7A18A pull on the latch which is in scribed with the unit identification 7 18 and the 7A18A will unlatch Continue pulling on the latch to slide the 7A18A out of the osciliscope FRONT PANEL CONTROLS AND CONNECTORS The following descriptions apply to the controls and con nectors of both Input Amplifier channels when applicable See Fig 2 1 Input Connector Provides signal connection to the channel AC GND AC Selects signal input coupling mode AC The AC component of t
124. table for use of this feature for slideback type measurements of peak or peak to peak high frequency or pulse waveforms exceeding 15 divisions peak to peak amplitude 4329 04 Fig 6 1 7A18A Option 06 mai E TIER CHARACTERISTICS AMPLIFIER LINEAR OFFSET RANGE Common mode DC range of the input amplifiers is sufficient to provide linear amplification of signals within normal 7A18A performance specifications at offsets of up to 200 divisions EFFECTIVE VOLTAGE OFFSET Effective voltage offset values for calibrated VOLTS DIV steps are as follows VARIABLE control in Cal position Table 6 1 EFFECTIVE OFFSET RANGE VOLTS DIV Direct With X10 Probe 5 mV HEN 10 2 20 20 4 40 50 10 100 4V 20 200 40 400 100 10002 1 200 20002 2 4001 40002 5 10001 10 0002 Maximum Input rating 250 when direct coupled Full offset range should not be used above 1 V DIV Maximum Input rating of most probes is 500 600 V Full offset range should not be used at VOLTS DIV settings above 2 with 10X probe CALIBRATION CALIBRATION Perform the following steps for checking Channel 1 and 2 OFFSET Range 6 2 amo Reset the Input coupling to GND and the VOLTS DIV to 5 mV and position the trace to the center horizontal grati cule line b Set the standard amplitude calibrator for
125. taching parts Attaching parts must be purchased separately unless otherwise specified ABBREVIATIONS INCH ELCTRN ELECTRON NUMBER SIZE ELEC ELECTRICAL ACTR gt ACTUATOR ELCTLT ELECTROLYTIC ADPTR ADAPTER ELEM ELEMENT ALIGN ALIGNMENT EPL ELECTRICAL PARTS LIST AL ALUMINUM EQUIPMENT ASSEM ASSEMBLED EXT EXTERNAL ASSY ASSEMBLY FIL FILLISTER HEAD ATTEN ATTENUATOR FLEX FLEXIBLE AWG AMERICAN WIRE GAGE FLAT BD BOARD FILTER FR FRAME or FRONT BRS BRASS FSTNR FASTENER BRONZE FT FOOT BSHG BUSHING FIXED CABINET GSKT GASKET CAP HDL HANDLE GER CERAMIC HEX HEXAGON CHAS CHASSIS HEX HD HEXAGONAL HEAD CKT CIRCUIT SOC HEXAGONAL SOCKET COMP COMPOSITION HLCPS HELICAL COMPRESSION CONN CONNECTOR HLEXT HELICAL EXTENSION HV FHGH VOLTAGE CPLG COUPLING IC INTEGRATED CIRCUIT CRT CATHODE RAY TUBE ID INSIDE DIAMETER DEG DEGREE IDENT IDENTIFICATION DWR DRAWER IMPLR IMPELLER IN INCH SE SINGLE ENG INCAND INCANDESCENT SECT SECTION INSUL INSULATOR SEMICOND SEMICONDUCTOR INTL INFERNAL SHLD SHIELD LPHLDA LAMPHOLDER SHLDR SHOULDERED MACH MACHINE SKT SOCKET MECH MECHANICAL SL SLIDE MTG MOUNTING SLFLKG SELF LOCKING NIP NIPPLE SLVG SLEEVING NON WIRE NOT WIRE WOUND SPR SPRING ORDER DESCRIPTION sa SQUARE OD OUTSIDE DIAMETER 551 STAINLESS STEEL OVH OVAL HEAD STL STEEL PH PHOSPHOR BRONZE Sw SWITCH PL PLAIN or PLATE a
126. the CH 1 and 2 coupling switches to the same position depending on the type of coupling desired 2 Set the DISPLAY MODE to ALT or CHOP in general CHOP is more suitable for low frequencies and ALT is more suitable for high frequencies Set the TRIGGER SOURCE to CH 1 3 Connect the reference signal to the CH 1 input and the comparison signal to the CH 2 input Use coaxial cables or probes which have similar time delay characteristics to connect the signals to the input connectors 4 the signals are of opposite polarity set the CH 2 POLARITY switch to invert the channel 2 display Signals may be of opposite polarity due to 180 phase difference if so take this into account in the final calculation 5 Set the VOLTS DIV switches and the VARIABLE Controls of the two channels so the displays are equal and about five divisions in amplitude 6 Set the time base unit to a sweep rate which displays about one cycle of the waveforms Set the Triggering con trols for a stable display 7 Center the waveforms on the graticule with the 7A18A POSITION controls 8 Adjust the time base Variable Time Div control until one cycle of the reference signal occupies exactly eight hori zontal divisions between the second and tenth vertical lines of the graticule see Fig 2 4 Each division of the graticule represents 45 of the cycle 360 8 divisions 45 divi sion The sweep rate can no
127. therlands Section 1 Section 2 TIONS TABLE OF CONTENTS Page SPECIFICATION Introduction 1 1 Electrical Characteristics 1 1 7A18A and Mainframe Frequency 305000596 ur vea a eo ee nne 1 1 Environmental Characteristics 1 2 Physical Characteristics 1 2 OPERATING INSTRUCTIONS Installation 2 1 Front Panel Controls and Connectors 2 1 General Operating Information 2 2 Basic Applications 2 4 FOLLOWING SERVICING INSTRUC ARE FOR USE BY QUALIFIED PER SONNEL ONLY TO AVOID PERSONAL INJU DO NOT PERFORM SERVICING OTHER THAN THAT CONTAINED IN OPER ATING INSTRUCTIONS UNLESS YOU QUALIFIED TO DO SO Section 3 Section 4 CIRCUIT DESCRIPTION Introduction 3 1 Block Diagram Description 3 1 Detailed Circuit Description 3 1 PERFORMANCE CHECK amp ADJUSTMENT Recalibration Interval 4 1 Test Equipment Required 4 1 Part Check 4 4 Part li Adjustment Section 5 Section 6 Section 7 Section 8 Section 9 Page MAINTENANCE Preventive Maintenance 5 1 Troubleshooting 5 1 Replacement Parts 5 3 Component Replacement 5 4 OPTION INFORMATION ELECTRICAL PARTS LIST Abbreviations and Symbols Parts Ordering Information DIAGRAMS A
128. through out its range d CHECK Trace alternation between Channel 1 and 2 at ali sweep rates At faster sweep rates alternation will not be apparent instead display appears as two traces on the screen 10 Check Chopped Operation a Set the DISPLAY MODE switch to CHOP b display for two traces 11 Check Trigger Source Operation a Change the following control settings Caiibration 74A18A DISPLAY MODE ALT TRIGGER SOURCE CH 1 b Connect the Indicator Oscilloscope Cal Out connector to the CH 1 input connector with the 18 inch BNC cable Set the time base unit for a triggered display at a sweep rate of 0 5 millisecond division d Connect the low frequency generator the CH 2 put connector with the 42 inch BNC cable e Set the generator for a two division 40 millivolts one kilohertz signal display for square wave and sine wave square wave only is stable g Set the TRIGGER SOURCE switch to MODE CHECK Crt display square wave and sine wave both stable i Set the TRIGGER SOURCE switch to CH 2 CHECK Crt display sine wave only is stable k Disconnect all test equipment This completes the Performance Check procedure for the 74184 If the instrument has met all tolerances given in this procedure it is correctly calibrated and within the specified limits PART li ADJUSTMENT Int
129. tion factors the resultant amplitude is diffi cult to determine from the crt display In this case the volt age amplitude of the resultant display can be determined accurately only if the amplitude of the signal applied to one channel is known In the ADD mode positioning of the trace 5 controlled by the channel 1 POSITION control only Chop Mode The CHOP position of the DISPLAY MODE Switch produces a display which is electronically switched between channels at approximately a 500 kHz rate con trolied by mainframe In general the CHOP mode provides the best display at sweep rates slower than about 0 2 millisecond division or whenever dual trace non repetitive phenomena 15 to be displayed Operating instructions 7A18A TRIGGER SOURCE Switch CH 1 The CH 1 position of the TRIGGER SOURCE switch provides a trigger signal obtained from the signal ap plied to the CH 1 input connector This provides a stable display of the signal applied to the CH 1 input connector CH 2 The CH 2 position of the TRIGGER SOURCE switch provides a trigger signal obtained from the signal ap plied to the CH 2 input connector This provides a stable display of the signal applied to the CH 2 input connector this position of the TRIGGER SOURCE switch the trigger signal for the time base unit is dependent on the setting of the DISPLAY MODE switch The trigger source for each position ofthe DISPLAY MODE switch is as follows MODE TRI
130. to Peak setting divisions factor Substituting the given values Volts Peak to Peak 45 X 1 X 10 The peak to peak voltage is 45 V instantaneous Voltage Measurements DC To measure the dc level at a given point on a waveform proceed as follows 1 Connect the signai to either input connector 2 Set the DISPLAY MODE and TRIGGER SOURCE _ Switches to display the channel used 3 Set the VOLTS DIV switch to display about five divi sions of the waveform 4 Set the coupling switch to GND and position the trace to the bottom graticule line or other reference line If the voltage is negative with respect to ground position the trace to the top graticule line Do not move the POSITION control after this reference line has been established NOTE To measure a voltage level with respect to a voltage other than ground make the following changes to step 4 Set the coupling switch to DC and apply the reference voltage to the input connector Then posi tion the trace to the reference line 5 Set the coupling switch to DC The ground reference line can be checked at any time by switching to the GND position 6 Set the time base Triggering controls for a stable dis olay Set the time base sweep rate for an optimum display waveform Operating Instructions 7A18A 7 Measure the distance in divisions between the refer ence line and the point on the waveform at which the dc level is to be measure
131. ts Supplemental information input R and C Resistance 1 12 Capacitance RC Product Approximately 20 0 pF Within 196 between all deflection factors Displayed Noise Tangentially Measured 0 06 div or less at all deflection factors 0 1 ms or less to recover to within one division after the removal of an overdrive signal of up to 75 divisions 75 divisions regardless of overdrive signal duration P Overdrive Recovery Time Common Mode Rejection Ratio At least 10 1 up to 50 megahertz DC Drift Drift with Time Ambient 0 02 division or less in any one minute temperature and line voltage after one hour warmup constant _ u Drift with Temperature line voltage Nor more than 0 01 division per degree constant C Time Delay between Channels 700 picoseconds or less Display Modes Channel 1 Dual trace alternate between channels Added algebraically Dual trace chopped between channels Channel 2 only Trigger source Selection Channel 1 only Follows DISPLAY MODE selection Channel 2 only Table 1 2 ENVIRONMENTAL CHARACTERISTIC lt _ Refer to the Specification for the associated oscilloscope A Table 1 3 PHYSICAL Size Fits all 7000 serie
132. tting 5 To measure the amplitude of an unknown signal dis connect the reference signal and connect the unknown sig nal to the input connector Set the VOLTS DIV switch to a setting that provides sufficient vertical deflection to make an accurate measurement Do not readjust the VARIABLE control 6 Measure the vertical deflection in divisions and calcu late the amplitude of the unknown signal using the following gt formula Signal VOLTS DIV vertical vertical Amplitude setting X conversion X deflection factor divisions EXAMPLE Assume a reference signal amplitude of 30 V a VOLTS DIV setting of 5 volts and the VARIABLE control adjusted to provide a vertical deflection of four divi sions Substituting these values in the vertical conversion factor formula step 4 30V i i 1 Vertical Conversion Factor 4X5V 5 Then with a VOLTS DIV setting of 2 V the peak to peak amplitude of an unknown signal which produces a vertical deflection of five divisions can be determined by using the signal amplitude formula step 6 Signal Amplitude 2VX 1 5 15 volts Dual Trace Phase Difference Measurements Phase comparison between two signals of the same E quency can be made using the dual trace feature of the This method of phase difference measurement can be used up to the frequency limit of the oscilloscope system To make the comparison use the following procedure 1 Set
133. uctors used in this instrument 5 2 Maintananra 194A ted used with this instrument is operating correctly possible Substitute an amplifier unit known to be operating correctly into the indicator unit and see if the problem persists Check that the inputs are properly connected and that the intercon necting cables are not defective 3 Visual Check Visually check the portion of the instru ment in which the trouble is suspected Many troubles can be located by visual indications such as unsoldered connec tions broken wires damaged circuit boards damaged com ponents etc 4 Check Instrument Performance Check the calibration of the unit or the affected circuit by performing Part I Performance Check of Section 4 The apparent trouble may be a result of misadjustment and may be corrected by calibration Complete calibration instructions are given in Part of Section 4 5 Check Voltages and Waveforms Often the defective component or stage can be located by checking for the cor rected voltage or waveform in the circuit Typical voltages and waveforms are given the diagrams howevever these are not absolute and may vary slightly between instru ment To obtain operating conditions similar to those used to take these readings see the instructions in the Diagrams Section 6 Check Individual Components The following methods are provided for checking the individual c
134. w be stated in terms of degrees as 45 division 9 Measure the horizontal difference between corre sponding points on the waveform 10 Multiply the measured distance in divisions by 45 division to obtain the exact amount of phase difference EXAMPLE Assume a horizontal difference of 0 3 divi sion with a sweep rate of 45 division as shown in Fig 2 4 Using the formula horizontal sweep rate Phase Difference difference X degrees division divisions Substituting the given values Phase Difference 0 3 X 45 The phase difference is 13 5 High Resolution Phase Measurements More accurate dual trace phase measurements can be made by increasing the sweep rate without changing the Variable Time Div control One of the easiest ways to in crease the sweep rate is with the time base Magnifier Switch Set the Magnifier to X10 and determine the magni fied sweep rate by dividing the sweep rate obtained previ ously by the amount of sweep magnification EXAMPLE If the sweep rate is increased 10 times by the Magnifier the magnified sweep rate is 45 division 10 4 Fig 2 5 shows the same signals as used in INSITLEUONS AI9A Channel 1 Channet 2 Lagging X Horizontal Difference 771 1126 42 Fig 2 4 Measuring phase difference between two signals Channel 1 __ Reference
135. wave output display for a five division display d If necessary adjust the front panel GAIN control for exactly five divisions of vertical deflection To adjust press E in the GAIN knob with screwdriver and turn until the GAIN control is engaged e Set the DISPLAY MODE switch to CH 2 and repeat parts c and d of this step for Channel 2 2 Check Channel 1 and 2 Deflection Factor Accuracy a Set the Channel 1 AC GND DC switch to GND b CHECK Using the VOLTS DIV and standard ampli tude calibrator settings given in Table 4 2 check vertical deflection within 2 in each position of the CH 2 VOLTS DIV switch c Change the following control settings DISPLAY MODE CH 1 CH 1 AC GND DC DC CH 2 AC GND DC GND d Repeat part b of this step for Channel 1 Table 4 2 Vertical Deflection Accuracy Standard Vertical Maximum VOLTS DIV Amplitude Deflection Error for 2 Switch Calibrator in Accuracy Setting Output Divisions divisions 5V 20 mV 4 0 08 10 mV 50 mV 5 Set in step 1 20 mV 0 1 V 5 04 50 mV 0 2 V 4 0 08 AV 05V 5 071 2 1 5 0 1 5V gt 2V 4 0 08 5V 5V 5 01 2 10 5 0 1 5V 20 V 4 0 08 3 Check Channel 1 and 2 VARIABLE VOLTS DIV Range a Set the Channel 1 and 2 VOLTS DIV switches to 10 mV and the standard amplitude calibrator for a 50 millivolt output b Press and release the VARIABLE control to its out ward position REV JUN 1983 Nr
136. y Signal and Trigger Output The Signal Output stage Q280 Q380 and the Trigger Output stage Q480 Q580 are similar Each stage consists of a pair of common base connected transistors which pro vide the dc level shifting necessary to drive the mainframe circuits Circuit Description 7A18A INPUT Display Trigger Mode Source Switch Switch OUTPUT Trigger Signal Source gt gt CH 1 r I Es CH 1 CH 1 CH 2 CH 1 Alternates between CH 1 and CH 2 CH 2 CH 1 CH 1 and CH 2 added CH 1 1 and 2 added 2 CH 1 CH 2 CH 2 I CH2 CH 1 MI e N ii __ Ec 1126 47 Fig 3 4 Input utput combinations for DISPLAY MODE and TRIGGER SOURCE switch selections DISPLAY MODE AND TRIGGER SWITCHING General The Display Mode and Trigger Switching circuit deter mines which input signal Channel 1 or Channel 2 provides the Signal and Trigger outputs to the mainframe as selected by the DISPLAY MODE and TRIGGER SOURCE switches This circuit also provides plug in mode information to the mainframe chop blanking circuit and readout control infor mation for proper crt display DISPLAY MODE Switch The DISPLAY MODE switch provides logic level outputs to the Signal Channel Switch stage U270 Channel Switch es Diagram 4 A table of the outputs for each positio
137. ylene ace tone or similar solvents Front Panel Loose dust may be removed with a soft cloth or a dry brush Water and mild detergent may be used however abrasive cleaners should not be used Interior Cleaning the interior of the unit should preceed calibration since the cleaning process could alter the settings of the calibration adjustments Use low velocity compressed air to blow off the accumulated dust Hardened dirt can be removed with a soft dry brush cotton tipped swab or cloth dampened with a mild detergent and water solution Lubrication Use a cleaning type lubricant on shaft bushings inter connecting plug and contacts Lubricate switch detents with information given under Trouble a heavier grease A lubrication kit containing their necessary lubricating materials and instructions is available through any Tektronix Field Office Order Tektronix Part Number 003 0342 02 Recalibration To ensure accurate measurements the 7A18A should be checked after each 1000 hours of operation or every six months if used infrequently A complete performance check procedure is given in Part of Section 4 The performance check procedure can be helpful in iso lating major troubles in the unit Moreover minor troubles not apparent during regular operation may be revealed and corrected TROUBLESHOOTING General The following is provided to augment information con tained in other sections of this manual when trou

Tektronix 7A18A User's Manual

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