Tektronix 1502B User manual

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Service Manual
1502B
Metallic Time-Domain Reflectometer
070-6267-04
This document applies for firmware version 5.02
and above.
Warning
The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
performanyservicingunlessyouarequalifiedtodo
so.RefertotheSafetySummarypriortoperforming
service.
First Printing: June 1996
Revised: February 1998

  
)+0 15:;9<4-5; 4)5<.)+;<9-, *@ $-2;9651? 0): ) :-91)3 5<4*-9 65 ) 7)5-3 15:-9; 69 ;)/ 69 :;)47-, 65 ;0-
+0)::1: $0- .19:; 3-;;-9 15 ;0- :-91)3 5<4*-9 ,-:1/5);-: ;0- +6<5;9@ 6. 4)5<.)+;<9- $0- 3):; .1=- ,1/1;: 6. ;0-
:-91)3 5<4*-9 )9- )::1/5-, :-8<-5;1)33@ )5, )9- <518<- ;6 -)+0 15:;9<4-5; $06:- 4)5<.)+;<9-, 15 ;0-
%51;-, #;);-: 6. 4-91+) 0)=- :1? <518<- ,1/1;: $0- +6<5;9@ 6. 4)5<.)+;<9- 1: 1,-5;1.1-, ): .6336>:
 $-2;9651? 5+ -)=-9;65 9-/65 %#
 $-2;9651? %51;-, 15/,64 ;, 65,65 5/3)5,
 #65@$-2;9651? )7)5
 $-2;9651? 633)5, & --9-5=--5 $0- -;0-93)5,:
5:;9<4-5;: 4)5<.)+;<9-, .69 $-2;9651? *@ -?;-95)3 =-5,69: 6<;:1,- ;0- %51;-, #;);-: )9- )::1/5-, )
;>6A,1/1; )370) +6,- ;6 1,-5;1.@ ;0- +6<5;9@ 6. 4)5<.)+;<9- -/ ! .69 )7)5  .69 652 65/  .69
:9)-3 -;+
$-2;9651? 5+ !  6?  -)=-9;65 9-/65  %#
!915;-, 15 %#
67@91/0; $-2;9651? 5+  33 91/0;: 9-:-9=-, $-2;9651? 796,<+;: )9- +6=-9-, *@ %# )5, .69-1/5
7);-5;: 1::<-, )5, 7-5,15/ $$" ( )5, $ )9- 9-/1:;-9-, ;9),-4)92: 6. $-2;9651? 5+
   
$01: -8<174-5; 0): *--5 ;-:;-, )5, .6<5, ;6 +6473@ >1;0 ;0- 3141;: .69 )
3)::  ,1/1;)3 ,-=1+- 7<9:<)5; ;6 !)9;  6. ;0-  "<3-: $0-:- 3141;: )9-
,-:1/5-, ;6 796=1,- 9-):65)*3- 796;-+;165 )/)15:; 0)94.<3 15;-9.-9-5+- 15 )
+644-9+1)3 -5=19654-5; $01: -8<174-5; /-5-9);-, <:-: )5, +)5 9),1);-
9),16 .9-8<-5+@ -5-9/@ )5, 1. 56; 15:;)33-, )5, <:-, 15 )++69,)5+- >1;0 ;0-
15:;9<+;165: 4)@ +)<:- 0)94.<3 15;-9.-9-5+- ;6 9),16 +644<51+);165: 7A
-9);165 6. ;01: -8<174-5; 15 ) 9-:1,-5;1)3 )9-) 1: 312-3@ ;6 +)<:- 0)94.<3 15;-9.-9A
-5+- 15 >01+0 +):- ;0- <:-9 >133 *- 9-8<19-, ;6 +699-+; ;0- 15;-9.-9-5+- ); 01:
6>5 -?7-5:-
0)5/-: 69 46,1.1+);165 56; -?79-::3@ )7796=-, *@ $-2;9651? +)5 )..-+;
-41::165 +64731)5+- )5, +6<3, =61, ;0- <:-9: )<;0691;@ ;6 67-9);- ;01:
-8<174-5;
$0-  -;)331+ $14-A64)15 "-.3-+;64-;-9 >): ,-:1/5-, )5, 4)5<.)+;<9-, *@
$-2;9651? 5+
 # '13:65 =-
-5, 9-/65  %#
!065- AA

Certificate of the Manufacturer/Importer
Bescheinigung des Herstellers/Importeurs
NOTICE to the user/operator:
e hereby certify that the Tektronix 1502B Metallic TDR complies with the RF
Interference Suppression requirements of Amtsbl.ĆVfg 1046/1984. The German
Postal Service was notified that the equipment is being marketed. The German
Postal Service has the right to reĆtest the series and to verify that it complies.
TEKTRONIX
Hiermit wird bescheinigt, dadas Tektronix 1502B Metallic TDR Übereinstimmung
mit den Bertimmungen der AmtsblattĆVerfügung 1046/1984 funkentstört ist. Der
Deutschen Bundespost wurde das Inverkehrbringen dieses Gerätes angezeigt
und die Bereschtigung zur Überprufung der Serie auf Einhalten der
Bestimmungen eingeraümt.
TEKTRONIX
The German Postal Service requires that this equipment, when used in a test setup,
may only be operated if the requirements of Postal Regulation, Vfg. 1046/1984, Par.
2, Sect. 1.7.1 are complied with.
Dieses Gerät darf in Meaufbauten nur betrieben werden, wenn die
Voraussetzungen des Par. 2, Ziff. 1.7.1 der Vfg. 1046/1984 eingehalten werden.
NOTICE to the user/operator:
The German Postal Service requires that systems assembled by the operator/user
of this instrument must also comply with Postal Regulation, Vfg. 243/1991, Par. 2,
Sect. 1.
HINWEIS für den Benutzer/Betreiber:
Die vom Betreiber zusammengestellte Anlage, innerhalb derer dieses Gerät
eingesetzt wird, muß ebenfalls den Voraussetzungen nach Par. 2, Ziff. 1 der Vfg.
243/1991, genügen.
HINWEIS für den Benutzer/Betriber:

WARRANTY
!               
   "       "      
"  !            
         !    
       "   " !     
!   "          
             
  " !     !  "    
             "    !
         "    
!  "       "  
 "   "  "      "     
    !         
"        "    !
              
                
              
 "    
THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THIS PRODUCT IN LIEU OF
ANY OTHER WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX AND ITS VENDORS
DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE. TEKTRONIX' RESPONSIBILITY TO REPAIR OR REPLACE
DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE
CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT
BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE
POSSIBILITY OF SUCH DAMAGES.

1502B MTDR Service Manual i
Table of Contents
List of Figures iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List of Tables viii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Safety Summary ix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Safety Summary xi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Information xiii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation and Repacking xiv. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating Instructions 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preparing to Use the 1502B 1–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Display 1–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front-Panel Controls 1–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Menu Selections 1–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test Preparations 1–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cable Test Procedure 1–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Additional Features (Menu Selected) 1–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operator Performance Checks 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical Characteristics 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Environmental Characteristics 3–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Physical Characteristics 3–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Options and Accessories 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option 03: Battery Pack 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option 04: YT–1 Chart Recorder 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option 05: Metric Default 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option 07: YT–1S Chart Recorder 4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Cord Options 4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accessories 4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Descriptions 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Supply 5–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Processor System 5–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option Port Interface 5–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Video Processor 5–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Timebase 5–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Elapsed Time Indicator (SN <B020511 only) 5–22. . . . . . . . . . . . . . . . . . . . . . . . . . .
Driver/Sampler 5–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Panel 5–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Display Module 5–29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents
ii 1502B MTDR Service Manual
Calibration 6–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction 6–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Calibration Performance Check 6–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Display Module Check 6–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Panel Check 6–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Horizontal Scale (Timebase) Check 6–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Zero Offset Check 6–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vertical Position (Offset) Check 6–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Noise Check 6–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sampling Efficiency Check 6–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Offset/Gain Check 6–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RAM/ROM Check 6–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Aberrations Check 6–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Risetime Check 6–19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jitter Check 6–21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option 03: Battery Pack Check 6–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option 04/07: YT-1/YT-1S Chart Recorder Check 6–23. . . . . . . . . . . . . . . . . . . . . . .
Option 05: Metric Default Check 6–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adjustment Procedures 6–24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Visual Inspection 6–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Supply Checks and Adjustments 6–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Board ”12 VDC Check and Adjust 6–29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Impedance Check 6–34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LCD Check and Adjustment 6–35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Zero Offset Adjust 6–38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
After Adjustments are Completed 6–40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance 7–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction 7–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preventive Maintenance 7–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Part Removal and Replacement 7–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 7–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Control Panel Installation 7–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Top and Bottom EMI Shield Installation 7–21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installing the Case Cover Over the Chassis 7–22. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replaceable Electrical Parts 8–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagrams 9–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replaceable Mechanical Parts 10–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents
1502B MTDR Service Manual iii
List of Figures
Figure 1–1: Rear Panel Voltage Selector, Fuse, AC Receptacle 1–1. . . . .
Figure 1–2: Display Showing Low Battery Indication 1–3. . . . . . . . . . . .
Figure 1–3: 1502B Front-Panel Controls 1–4. . . . . . . . . . . . . . . . . . . . . .
Figure 1–4: Display and Indicators 1–5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–5: Vp Set at .30, Cursor Beyond Reflected Pulse
(Set Too Low) 1–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–6: Vp Set at .99, Cursor Less Than Reflected Pulse
(Set Too High) 1–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–7: Vp Set at .66, Cursor at Reflected Pulse (Set Correctly) 1–12
Figure 1–8: 20-ft Cable at 5 ft/div 1–12. . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–9: Short in the Cable 1–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–10: Open in the Cable 1–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–11: 455-ft Cable 1–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–12: 455-ft Cable 1–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–13: Reflection Adjusted to One Division in Height 1–15. . . . . . .
Figure 1–14: Return Loss 1–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–15: Ohms-at-Cursor 1–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–16: Display with VIEW INPUT Turned Off 1–18. . . . . . . . . . . . .
Figure 1–17: Display of a Stored Waveform 1–18. . . . . . . . . . . . . . . . . . . .
Figure 1–18: Display of a Stored Waveform 1–18. . . . . . . . . . . . . . . . . . . .
Figure 1–19: Waveform Moved to Top Half of Display 1–19. . . . . . . . . . . .
Figure 1–20: Current Waveform Centered, Stored Waveform Above 1–20.
Figure 1–21: Current Waveform Center, Stored Waveform Above,
Difference Below 1–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–22: Waveform of Three-Foot Lead-in Cable 1–21. . . . . . . . . . . . .
Figure 1–23: Cursor Moved to End of Three-Foot Lead-in Cable 1–22. . . .
Figure 1–24: Cursor Moved to End of Three-Foot Lead-in Cable 1–22. . . .
Figure 1–25: Cursor Moved to 0.00 ft 1–23. . . . . . . . . . . . . . . . . . . . . . . . .
Figure 1–26: Incident Pulse at Three Divisions 1–23. . . . . . . . . . . . . . . . . .
Figure 1–27: Waveform of Short 75WCable 1–24. . . . . . . . . . . . . . . . . . . .
Figure 1–28: Waveform Centered and Adjusted Vertically 1–24. . . . . . . . .
Figure 1–29: Cursor Moved to Desired Position 1–25. . . . . . . . . . . . . . . . .
Figure 1–30: Waveform Viewed in Normal Operation 1–26. . . . . . . . . . . . .
Figure 1–31: Waveform Showing Intermittent Changes 1–26. . . . . . . . . . .
Figure 1–32: Waveform Display with No Outgoing Pulses 1–27. . . . . . . . .
Figure 1–33: A Captured Single Sweep 1–28. . . . . . . . . . . . . . . . . . . . . . . .

Contents
iv 1502B MTDR Service Manual
Figure 2–1: Start-up Measurement Display 2–2. . . . . . . . . . . . . . . . . . . .
Figure 2–2: Measurement Display with 3-foot Cable 2–2. . . . . . . . . . . .
Figure 2–3: Cursor at End of 3-foot Cable 2–3. . . . . . . . . . . . . . . . . . . . .
Figure 2–4: Flat-Line Display Out to 50,000+ Feet 2–3. . . . . . . . . . . . . .
Figure 2–5: Flat-Line Display at –2.000 ft 2–4. . . . . . . . . . . . . . . . . . . . .
Figure 2–6: Waveform Off the Top of the Display 2–4. . . . . . . . . . . . . . .
Figure 2–7: Waveform at the Bottom of the Display 2–5. . . . . . . . . . . . .
Figure 2–8: Waveform with Gain at 5.00 mr/div 2–5. . . . . . . . . . . . . . .
Figure 2–9: Top of Pulse on Center Graticule 2–7. . . . . . . . . . . . . . . . . .
Figure 2–10: Rising Edge of Incident Pulse in Left-most
Major Division 2–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–11: Waveform Centered, Cursor at 0.000 ft 2–8. . . . . . . . . . . . .
Figure 2–12: Pulse Centered on Display 2–8. . . . . . . . . . . . . . . . . . . . . . .
Figure 2–13: Cursor on Lowest Major Graticule that Rising Edge
crosses 2–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–14: Cursor on Highest Major Graticule that Rising Edge
crosses 2–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–15: Jitter Apparent on Leading Edge of Incident Pulse 2–10. . . .
Figure 2–16: Jitter Captured Using Max Hold 2–10. . . . . . . . . . . . . . . . . . .
Figure 5–1: System Block Diagram 5–2. . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–2: Waveform Accumulation Diagram 5–3. . . . . . . . . . . . . . . . .
Figure 5–3: Power Supply Block Diagram 5–4. . . . . . . . . . . . . . . . . . . . .
Figure 5–4: Processor Block Diagram 5–8. . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–5: Option Port Interface Block Diagram 5–11. . . . . . . . . . . . . . .
Figure 5–6: Video Processor Block Diagram 5–13. . . . . . . . . . . . . . . . . . .
Figure 5–7: Video Processor Output 5–15. . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–8: Timebase Block Diagram 5–16. . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–9: Timebase Control 5–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–10: Combined Effects of Time Delay 5–18. . . . . . . . . . . . . . . . . .
Figure 5–11: Calibration of Delay Zero and 50-ns Analog Delay 5–19. . . .
Figure 5–12: Driver/Sampler Block Diagram 5–24. . . . . . . . . . . . . . . . . . .
Figure 5–13: Front Panel Block Diagram 5–26. . . . . . . . . . . . . . . . . . . . . . .
Figure 5–14: Display Module Block Diagram 5–29. . . . . . . . . . . . . . . . . . .
Figure 5–15: SBE Cell 5–31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–16: Row Driver Block Diagram 5–31. . . . . . . . . . . . . . . . . . . . . .
Figure 5–17: Column Driver Block Diagram 5–32. . . . . . . . . . . . . . . . . . . .
Figure 5–18: Row Timing Diagram 5–34. . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–19: Column Timing Diagram 5–35. . . . . . . . . . . . . . . . . . . . . . . .

Contents
1502B MTDR Service Manual v
Figure 5–20: Shift Register 5–37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–21: CPU and Display Memory Interface 5–39. . . . . . . . . . . . . . . .
Figure 6–1: Typical Start-Up Display 6–2. . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–2: Waveform on the Display 6–2. . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–3: Setup Menu 6–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–4: Main Menu 6–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–5: Diagnostics Menu 6–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–6: Front Panel Diagnostic Display 6–5. . . . . . . . . . . . . . . . . . . .
Figure 6–7: Front Panel Diagnostic Display 6–6. . . . . . . . . . . . . . . . . . . .
Figure 6–8: Front Panel Diagnostic Display 6–6. . . . . . . . . . . . . . . . . . . .
Figure 6–9: Front Panel Diagnostic Display 6–7. . . . . . . . . . . . . . . . . . . .
Figure 6–10: Waveform on the Display with No Cable Attached 6–8. . . .
Figure 6–11: Display with 3-ft Cable and Stored Waveform 6–8. . . . . . . .
Figure 6–12: Cursor on Rising Edge of Pulse 6–9. . . . . . . . . . . . . . . . . . .
Figure 6–13: Cursor at 0.000 ft 6–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–14: Cursor on Rising Edge of Pulse 6–9. . . . . . . . . . . . . . . . . . .
Figure 6–15: Flatline Display to >2,000 ft 6–10. . . . . . . . . . . . . . . . . . . . . .
Figure 6–16: Incident Pulse at –2.000 ft 6–11. . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–17: Incident Pulse at –2.000 ft with 3-ft Cable Connected 6–11. .
Figure 6–18: Incident Pulse at –2.000 ft with Max Hold 6–11. . . . . . . . . . .
Figure 6–19: Waveform at Top of the Display 6–12. . . . . . . . . . . . . . . . . .
Figure 6–20: Waveform at Bottom of the Display 6–13. . . . . . . . . . . . . . . .
Figure 6–21: Waveform at Centered 6–13. . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–22: Cursor Moved to 100.000 ft 6–14. . . . . . . . . . . . . . . . . . . . . .
Figure 6–23: Noise with Gain at 5.00 mr6–14. . . . . . . . . . . . . . . . . . . . . .
Figure 6–24: Noise Diagnostic Display 6–15. . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–25: Service Diagnostic Menu 6–15. . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–26: Service Diagnostic Menu 6–16. . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–27: Service Diagnostic Menu 6–17. . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–28: Waveform with Cursor at –2.000 ft 6–18. . . . . . . . . . . . . . . . .
Figure 6–29: Waveform at 50 mr/div 6–18. . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–30: Waveform at 5 mr/div 6–19. . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–31: Incident Pulse at Center of Display 6–19. . . . . . . . . . . . . . . . .
Figure 6–32: Incident Pulse Centered, Vertical Increased 6–20. . . . . . . . . .
Figure 6–33: Cursor on Rising Edge at First Horizontal Graticule 6–20. . .
Figure 6–34: Cursor on Rising Edge at Last Horizontal Graticule 6–21. . .
Figure 6–35: Rising Edge at Center of Display 6–22. . . . . . . . . . . . . . . . . .
Figure 6–36: Rising Edge with Scale at 1.0 mr/div 6–22. . . . . . . . . . . . . . .