Tektronix TDS1001B, TDS1002B, TDS1012B, TDS2002B, TDS2004B Service

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Service Manual

TDS1000B and TDS2000B Series Digital Storage Oscilloscopes

077-0356-00

*P077035600*

077035600

Service Manual

TDS1000B and TDS2000B Series Digital Storage Oscilloscopes

077-0356-00

This document applies to firmware version 1.00 and above.

Warning

The servicing instructions are for use by qualified personnel only. To avoid personal injury, do not perform any servicing unless you are qualified to do so. Refer to all safety summaries prior to performing service.

www.tektronix.com

Copyright © Tektronix. All rights reserved. Licensed software products are owned by Tektronix or its subsidiaries or suppliers, and are protected by national copyright laws and international treaty provisions.

Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes that in all previously published material. Specifica tions and price change privileges reserved.

TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

OpenChoicet is a registered trademark of Tektronix, Inc.

Contacting Tektronix

Tektronix, Inc. 14200 SW Karl Braun Drive P.O. Box 500 Beaverton, OR 97077 USA

For product information, sales, service, and techni cal support:

H In North America, call 1-800-833-9200. H Worldwide, visit www.tektronix.com to find contacts in your area.

Table of Contents

General Safety Summary v...................................

Service Safety Summary vii....................................

Preface ix...................................................

Manual Conventions ix..............................................

Related Documentation ix...........................................

Specifications 1--1.............................................

Operating Information 2--1.....................................

Theory of Operation 3--1.......................................

Main Board 3--4.....................................................

Acquisition System 3 --4...........................................

Processing and Display System 3--5..................................

Input Signal Interface 3--5.........................................

Probe Compensation 3--5..........................................

External Trigger 3--5.............................................

Main Board Power 3--5............................................

Power Supply 3--6...................................................

Display Module 3--6.................................................

Front Panel 3--6.....................................................

Two-Channel Oscilloscopes 3--6....................................

Four-Channel Oscilloscopes 3--7....................................

Performance V erification 4--1...................................

Required Equipment 4--1..............................................

Test Record 4--2.....................................................

Performance Verification Procedures 4--3.................................

Self Test 4--3....................................................

Self Calibration 4--3..............................................

Check DC Gain Accuracy 4--4......................................

Check Bandwidth 4--5............................................

Check Sample Rate Accuracy and Delay Time Accuracy 4--6.............

Check Edge Trigger Sensitivity 4--8.................................

Check External Edge Trigger Sensitivity 4--9..........................

Check Vertical Position Accuracy 4--11................................

Adjustment Procedures 5--1.....................................

Required Equipment 5--1..............................................

Adjustment Procedure 5--2............................................

Enable the Service Menu 5--2......................................

Adjustment Procedure 5--5.........................................

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Table of Contents

Maintenance 6--1..............................................

Preventing ESD 6--1.................................................

Inspection and Cleaning 6--2...........................................

General Care 6--2................................................

Interior Cleaning 6--2.............................................

Exterior Cleaning 6--2............................................

Removal and Installation Procedures 6--6.................................

List of Modules 6--6..............................................

Summary of Procedures 6--6.......................................

Required Tools 6--8...............................................

Rear Feet 6--8...................................................

Flip Feet 6--8....................................................

Front-Panel Knobs 6--9............................................

Power Button 6--9................................................

Rear Case 6--9...................................................

Front Feet 6--10...................................................

Power Supply Module 6--11.........................................

Internal Assembly 6-- 12............................................

Display Cable 6--12...............................................

Front-Panel Cable 6--14............................................

Main Board Module 6--15..........................................

Display Module 6--16..............................................

Front-Panel Module 6--18...........................................

Keypad 6--18.....................................................

Front Case 6--19..................................................

Troubleshooting 6--20.................................................

Adjustment After Repair 6--20.......................................

Required Tools and Equipment 6--20..................................

Troubleshooting Tree 6--20.........................................

PROBE COMP Output 6--25........................................

Troubleshooting the Power Supply 6--25..............................

Troubleshooting the Display 6--26...................................

Troubleshooting the Backlight 6--28..................................

Troubleshooting the Front Panel 6--30.................................

Troubleshooting the Main Board 6--32................................

Running Diagnostics 6--33..........................................

Troubleshooting Input Connections 6--33..............................

Troubleshooting the USB Interface 6--34...............................

Using the Error Log 6--34...........................................

Repackaging Instructions 6--36..........................................

Packaging 6--36..................................................

Storage 6--36.....................................................

Diagrams 7--1.................................................

Replaceable Parts 8--1..........................................

Parts Ordering Information 8--1.........................................

Using the Replaceable Parts List 8--3....................................

Appendix A: Example of a Vertical Position Accuracy Test

Spreadsheet A--1...........................................

Index

TDS1000B and TDS2000B Series Oscilloscope Service Manual

List of Figures

Table of Contents

Figure 3--1: Module-level block diagram (two channel) 3--2..........

Figure 3--2: Module-level block diagram (four channel) 3--3..........

Figure 4--1: Example of a line gr aph for the Vertical Position Accuracy

test 4--14...................................................

Figure 5--1: Adjustment setups 5--4...............................

Figure 6--1: Locator for trim and cabinet removal 6--7...............

Figure 6--2: Locator for internal modules 6--7......................

Figure 6--3: Securing the display cable to the chassis 6--14............

Figure 6--4: Oscilloscope troubleshooting tree (1 of 4) 6--21............

Figure 6--5: Oscilloscope troubleshooting tree (2 of 4) 6--22............

Figure 6--6: Oscilloscope troubleshooting tree (3 of 4) 6--23............

Figure 6--7: Oscilloscope troubleshooting tree (4 of 4) 6--24............

Figure 6--8: Measuring the backlight voltage 6--29...................

Figure 7--1: TDS1000B and TDS2000B series block diagram 7--2......

Figure 8--1: Exploded diagram, 2-channel models 8--5...............

Figure 8--2: Exploded diagram, 4-channel models 8--7...............

Figure 8--3: Exploded diagram, power supply module, cables

and wires 8--9.............................................

Figure 8--4: Exploded diagram, back case and trim 8--11.............

TDS1000B and TDS2000B Series Oscilloscope Service Manual

iii

Table of Contents

List of Tables

Table 1--1: Oscilloscope specifications 1--1........................

Table 1--2: Oscilloscope general specifications 1--8..................

Table 5--1: Required equipment 5--1.............................

T able 5--2: Adjustment steps 5--6................................

T able 6--1: External inspection check list 6--3......................

T able 6--2: Internal inspection check list 6--4......................

Table 6--3: List of procedures 6--7...............................

Table 6--4: List of error codes 6--34...............................

Table 8--1: Replaceable parts list, 2-channel models 8--4.............

Table 8--2: Replaceable parts list, 4-channel models 8--6.............

Table 8--3: Replaceable parts list, power supply module, cables,

and wires 8--8.............................................

T able 8--4: Replaceable parts list, back case and trim 8--10...........

T able 8--5: Standard accessories 8--12.............................

Table 8--6: Optional accessories 8--12..............................

TDS1000B and TDS2000B Series Oscilloscope Service Manual

General Safety Summary

Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it.

To avoid potential hazards, use this product only as specified.

Only qualified personnel should perform service procedures.

ToAvoidFireor

Personal Injury

Use Proper Power Cord. Use only the power cord specified for this product and certified for the country of use.

Connect and Disconnect Properly. Connect the probe output to the measurement instrument before connecting the probe to the circuit under test. Connect the probe reference lead to the circuit under test before connecting the probe input. Disconnect the probe input and the probe reference lead from the circuit under test before disconnecting the probe from the measurement instrument.

Ground the Product. This product is grounded through the grounding conductor of the power cord. To avoid electric shock, the grounding conductor must be connected to earth ground. Before making connections to the input or output terminals of the product, ensure that the product is properly grounded.

Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings and markings on the product. Consult the product manual for further ratings information before making connections to the product.

Connect the probe reference lead to earth ground only.

Do not apply a potential to any terminal, including the common terminal, that exceeds the maximum rating of that terminal.

Power Disconnect. The power switch disconnects the product from the power source. See instructions for the location. Do not block the power switch; it must remain accessible to the user at all times.

Do Not Operate Without Covers. Do not operate this product with covers or panels removed.

Do Not Operate With Suspected Failures. If you suspect there is damage to this product, have it inspected by qualified service personnel.

Avoid Exposed Circuitry. Do not touch exposed connections and components when power is present.

Do Not Operate in Wet/Damp Conditions.

Do Not Operate in an Explosive Atmosphere.

Keep Product Surfaces Clean and Dry.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

General Safety Summary

Provide Proper Ventilation. Refer to the manual’s installation instructions for details on installing the product so it has proper ventilation.

Terms in this Manual

Symbols and Terms

on the Product

These terms may appear in this manual:

WARNING. Warning statements identify conditions or practices that could result in injury or loss of life.

CAUTION. Caution statements identify conditions or practices that could result in damage to this product or other property.

These terms may appear on the product:

H DANGER indicates an injury hazard immediately accessible as you read the

marking.

H WARNING indicates an injury hazard not immediately accessible as you

read the marking.

H CAUTION indicates a hazard to property including the product.

The following symbols may appear on the product:

CAUTION

Refer to Manual

Mains Connected

ON (Power)

Protective Ground

(Earth) Terminal

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Earth Terminal

Chassis Ground

Mains Disconnected

OFF (Power)

Service Safety Summary

Only qualified personnel should perform service procedures. Read this Service Safety Summary and the General Safety Summary before performing any service

procedures.

Do Not Service Alone. Do not perform internal service or adjustments of this product unless another person capable of rendering first aid and resuscitation is present.

Disconnect Power. To avoid electric shock, switch off the instrument power, then disconnect the power cord from the mains power.

Use Care When Servicing With Power On. Dangerous voltages or currents may exist in this product. Disconnect power, remove battery (if applicable), and disconnect test leads before removing protective panels, soldering, or replacing components.

To avoid electric shock, do not touch exposed connections.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

vii

Service Safety Summary

viii

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Preface

Manual Conventions

This service manual provides information to verify performance of, calibrate, troubleshoot, disassemble, and replace parts on the TDS1000B and TDS2000B Series Digital Storage Oscilloscopes.

Unless noted otherwise, the term “oscilloscope” refers to all models in the TDS1000B and TDS2000B series.

This manual uses certain conventions that you should become familiar with before attempting service.

Modules

Replaceable Parts

Safety

Specifications

These specifications apply to all TDS1000B and TDS2000B series oscilloscopes. To verify that an oscilloscope meets specifications, it must first meet the following conditions:

H The oscilloscope must have been operating continuously for twenty minutes

H You must perform the Do Self Cal operation, accessible through the Utility

H The oscilloscope must be within the factory calibration interval of one year.

Specifications begin in Table 1--1. All specifications are guaranteed unless noted “typical.” Specifications that are marked with the n symbol are checked in the chapter Performance Verification.

Table 1- 1: Oscilloscope specifications

Acquisition

within the specified operating temperature.

menu, if the operating temperature has changed by more than 5 °C(9°F)

since the last time the Do Self Cal operation was performed.

Acquisition Modes Sample, Peak Detect, and Average

Acquisition Rate, typical

Single Sequence Acquisition Mode Acquisition Stops After

Up to 180 waveforms per second, per channel (Sample acquisition mode, no measurements)

Sample, Peak Detect Single acquisition, all channels simultaneously

Average N acquisitions, all channels simultaneously. N is selectable from 4,

16, 64, and 128

TDS1000B and TDS2000B Series Oscilloscope Service Manual

1- 1

Specifications

Ref

ati

BNC

fth

val

ceeded,d

ama

cil

losc

Table 1- 1: Oscilloscope specifications (Cont.)

Inputs

Input Coupling DC, AC, or GND

Input Impedance, DC Coupled

P2220 Probe Attenuation

Supported Probe Attenuation Factors

Supported Current Probe Scales

Maximum Voltage Overvoltage Category* Maximum Voltage Between Signal and

erence

npu

BNC

1MΩ ±2% in parallel with 20 pF ±3pF

1X, 10X

1X, 10X, 20X, 50X, 100X, 500X, 1000X

5 V/A, 1 V/A, 500 mV/A, 200 mV/A, 100 mV/A, 20 mV/A, 10 mV/A, 1 mV/A

CAT I and CAT II 300 V

RMS

Derate at 20 dB/decade above 100 kHz to 13 V peak AC at 3 MHz

For non-sinusoidal waveforms, peak value must be less than 450 V. Excursion above 300 V should be less than 100 ms duration and the duty factor is limited to ≤ 44%.

{

and above.

RMS signal level including any DC component removed through AC coupling must be limited to 300 V.

ese

Channel-to-Channel Common Mode Rejection, typical

uesare e

TDS1001B TDS1002B, TDS2002B,

TDS2004B

100:1 at 60 Hz 20:1at20MHz

{

100:1 at 60 Hz 20:1at30MHz

ge to theos

{

ope m

result.

TDS1012B, TDS2012B, TDS2014B, TDS2022B, TDS2024B

100:1 at 60 Hz 10:1at50MHz

{

Measured on MATH Ch1 -- Ch2 waveform, with test signal applied between signal and common of both channels, and with the same VOLTS/DIV and coupling settings on each channel

Measured on MATH Ch3 -- Ch4 waveform for 4-channel models

Channel-to-Channel Crosstalk

TDS1001B TDS1002B, TDS2002B,

TDS2004B

≥ 100:1 at 20 MHz{≥ 100:1 at 30 MHz

{

TDS1012B, TDS2012B, TDS2014B

≥ 100:1 at 50 MHz

{

TDS2022B, TDS2024B

≥ 100:1 at 100 MHz

Measured on one channel, with test signal applied between signal and common of the other channel, and with the same VOLTS/DIV and coupling settings on each channel

Refer to the Overvoltage Category description in the TDS1000B and TDS2000b User manual, available on the Tektronix Web site at www.tektronix.com/manuals.

{

Bandwidth reduced to 6 MHz with a 1X probe.

{

1- 2

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Specifications

VerticalPositio

inSampleandAverag

typical

Table 1- 1: Oscilloscope specifications (Cont.)

Verticalw

Digitizers 8-bit resolution (except when set to 2 mV/div), each channel sampled simultaneously

VOLTS/DIV Range 2 mV/div to 5 V/div at input BNC

Position Range, typical 2 mV/div to 200 mV/div, ±2V

> 200 mV/div to 5 V/div, ±50 V

n Vertical Position

Accuracy

n Analog Bandwidth

in Sample and Average modes at BNC or with P2220 probe set to 10X, DC Coupled

Analog Bandwidth in Peak Detect mode (50 s/div to 5 s/div}),

Selectable Analog Bandwidth Limit, typical

Lower Frequency Limit, AC Coupled

Rise Time at BNC, typical

Peak Detect Response}Captures 50% or greater amplitude of pulses ≥12 ns wi de typical (50 s/div to 5 s/div) in the center 8

Measurement Type Volts/Div Setting Position Accuracy

Accuracy of the nominal voltage level represented by the code at the center of the dynamic range of the A/D converter

TDS1001B TDS1002B, TDS2002B,

TDS2004B

40 MHz*{

20 MHz* (when vertical scale is set to < 5 mV)

TDS1001B TDS1002B, TDS2002B,

30 MHz*{ 50 MHz*{ 75 MHz*{

20 MHz* (when vertical scale is set to < 5 mV)

20 MHz*

≤ 10 Hz at BNC ≤ 1 Hz when using a 10X passive probe

TDS1001B TDS1002B, TDS2002B,

< 8.4ns <5.8ns <3.5ns <2.1ns

vertical divisions

60 MHz*{ 100 MHz*{ 200 MHz*{

TDS2004B

2 mV/div to 200 mV/div ±(1% X selected value + 0.1 div + 5 mV) within the range ±1.8 V

> 200 mV/div to 5 V/div ±(1% X selected value + 0.1 div + 125 mV) within the range ±45 V

TDS1012B, TDS2012B, TDS2014B

TDS1012B, TDS2012B, TDS2014B, TDS2022B, TDS2024B

TDS1012B, TDS2012B, TDS2014B

TDS2022B, TDS2024B

0 °Cto+35°C(32°Fto95°F)

160 MHz*{ 0 °Cto+50°C(32°F to 122 °F)

TDS2022B, TDS2024B

For TDS1001B, the pulse must be at least 13 ns wide

w Specifications are with the Probe " Voltage " Attenuation option set to 1X.

The “selected value” is the offset value indicated by the oscilloscope in the hint line (not the measurement).

* Bandwidth reduced to 6 MHz with a 1X probe and the Bandwidth Limit is turned off.

{ When vertical scale is set to ≥ 5mV.

}

The oscilloscope reverts to Sample mode when the SEC/DIV (horizontal scale) is set from 2.5 s/div to 5 ns/div on 1 GS/s models, or from 2.5 s/div to 2.5 ns/div on 2 GS/s models. The Sample mode can still capture 10 ns glitches.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

1- 3

Specifications

DCGainAccurac

idth)

Table 1- 1: Oscilloscope specifications (Cont.)

Verticalw

n DC Gain Accuracy

Volts Measurement Repeatability, Average Acquisition Mode

DC Measurement Measurement Type Accuracy Accuracy, Average Acquisition Mode

Horizontal

Sample Rate Range TDS1001B, TDS1002B, TDS2004B,

Waveform Interpolation (sin x)/x

Record Length 2500 samples for each channel

SEC/DIV Range TDS1001B, TDS1002B, TDS2004B,

n Sample Rate and

Delay Time Accuracy

Delta Time Measurement Conditions Accuracy Accuracy (Full Bandw

Position Range TDS1001B, TDS1002B, TDS2004B, TDS1012B, TDS2002B, TDS2012B, TDS2014, TDS2022B, TDS2024B

w Specifications are with the Probe " Voltage " Attenuation option set to 1X.

±3% for Sample or Average acquisition mode, 5 V/div to 10 mV/div

±4% for Sample or Average acquisition mode, 5 mV/div and 2 mV/div

Delta volts between any two averages of ≥ 16 waveforms acquired under same setup and ambient conditions

Average of ≥ 16 waveforms with vertical position at zero

Average of ≥ 16 waveforms with vertical scale with Vertical Scale 2 mV/div to 200 mV/div and

-1.8 V < Vertical Position < 1.8V

Average of ≥ 16 waveforms with vertical position with Vertical Scale > 200 mV/div and

-45 V < Vertical Position < 45 V

TDS1012B, TDS2002B, TDS2012B, TDS2014B

5S/sto1GS/s 5S/sto2GS/s

TDS1012B, TDS2002B, TDS2012B, TDS2014B

5 ns/div to 50 s/div, in a 1, 2.5, 5 sequence 2.5 ns/div to 50 s/div, in a 1, 2.5, 5 sequence

±50 parts per million (ppm) over any ≥1 ms time interval

Single-shot, Sample mode ±(1 sample interval + 100 ppm × reading + 0.6 ns)

> 16 averages ±(1 sample interval + 100 ppm × reading + 0.4 ns)

Sample interval = s/div ÷ 250

5ns/divto10ns/div (--4 div × s/div) to 20 ms

25 ns/div to 100 s/div (--4 div × s/div) to 50 ms

250 s/divto10s/div (--4 div × s/div) to 50 s

25 s/div to 50 s/div (--4 div × s/div) to 250 s

TDS2022B, TDS2024B

2.5 ns/div (--4 div × s/div) to 20 ms

±(3% × reading + 0.05 div)

±(3% × reading + 0.1 div + 1 mV) when 10 mV/div or

greater is selected

±[3% × (reading + vertical position) + 1% of vertical position + 0.2 div + 7 mV]

±[3% × (reading + vertical position) + 1% of vertical position + 0.2 div +175 mV]

TDS2022B, TDS2024B

1- 4

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Table 1- 1: Oscilloscope specifications

qy,typic

ggy

tDC

typical

Trigger

Specifications

n Trigger Sensitiv-

ity, Edge Trigger Type, DC coupling, with a stable display of a trigger event

Trigger Sensitivity, Edge Trigger Type, DC Coupling, Frequency Counter,

Coupling Sensitivity TDS1001B, TDS1002B,

TDS1012B, TDS2002B, TDS2004B, TDS2012B, TDS2014B

DC EXT 200 mV from DC to 100 MHz* 200 mV from DC to 100 MHz*

EXT/5 1 V from DC to 100 MHz* 1 V from DC to 100 MHz*

CH1, CH2, CH3, CH4

≥5mV/div

CH1, CH2, CH3, CH4

2mV/div

Coupling Sensitivity TDS1001B, TDS1002B,

EXT 300 mV from DC to 100 MHz* 300 mV from DC to 100 MHz*

1 div from DC to 10 MHz*

1.5 div from 10 MHz to Full

2.5 div from DC to 10 MHz*

4divfrom10MHzto20MHz

TDS1012B, TDS2002B, TDS2004B, TDS2012B, TDS2014B

TDS2022B, TDS2024B

350 mV from 100 MHz to 200 MHz*

1.75 V from 100 MHz to 200 MHz*

1 div from DC to 10 MHz*

1.5 div from 10 MHz to 100 MHz

2 div from 100 MHz to Full

TDS2022B, TDS2024B

EXT/5 1.5 V from DC to 100 MHz* 1.5 V from DC to 100 MHz*

CH1, CH2, CH3, CH4

≥5mV/div

CH1, CH2, CH3, CH4

2mV/div

Trigger Sensitivity, Coupling Sensitivity Edge Trigger Type, no typical

* Bandwidth reduced to 6 MHz with a 1X probe.

oup

ng,

AC Same as DC at 50 Hz and above

NOISE REJ Reduces the DC-coupled trigger sensitivity by 2 times for > 10 mV/div to 5 V/div

HF REJ Same as the DC-coupled limit from DC to 7 kHz, attenuates signals above 80 kHz

LF REJ Same as the DC-coupled limits for frequencies above 300 kHz, attenuates signals

below 300 kHz

500 mV from 100 MHz to 200 MHz*

3 V from 100 MHz to 200 MHz*

1.5 div from DC to 10 MHz*

3 div from 10 MHz to Full

4 div from DC to 10 MHz*

7.5 div from 10 MHz to 20 MHz

TDS1000B and TDS2000B Series Oscilloscope Service Manual

1- 5

Specifications

ggg

y,g

Table 1- 1: Oscilloscope specifications (Cont.)

Trigger

Trigger Level Range, Source Range typical

Trigger Level Accura- Accuracies are for signals having rise and fall times ≥ 20 ns cy, typical

SET LEVEL TO 50%, typical

Default Settings, Video Trigger

Sensitivity, Video Trig- Composite video signal ger Type, typical

Signal Formats and Field Rates, Video Trigger Type

CH1, CH2, CH3, CH4 ±8 divisions from center of screen

EXT ±1.6 V

EXT/5 ±8V

AC Line Can not be set

Source

Internal

EXT ±(6% of setting + 40 mV) for signals within ±800 mV

EXT/5 ±(6% of setting + 200 mV) for signals within ±4V

Operates with input signals ≥ 50 Hz

Coupling is AC and Auto mode except for a single sequence acquisition

Source Range

Internal Peak-to-peak amplitude of 2 divisions

EXT 400 mV

EXT/5 2V

Supports NTSC, PAL, and SECAM broadcast systems for any field or any line

Accuracy

±0.2 div × volts/div within ±4 divisions from center screen

Holdoff Range 500 ns to 10 s

Pulse Width trigger

Pulse Width Trigger modes

Pulse Width Trigger Point

1- 6

Trigger when < (Less than), > (Greater than), = (Equal), or ≠ (Not Equal); Positive pulse or Negative pulse

Equal: The oscilloscope triggers when the trailing edge of the pulse crosses the trigger level.

Not Equal: If the pulse is narrower than the specified width, the trigger point is the trailing edge. Otherwise, the oscilloscope triggers when a pulse continues longer than the time specified as the Pulse Width.

Less than: The trigger point is the trailing edge.

Greater than (also called time-out trigger): The oscilloscope triggers when a pulse continues longer than the time specified as the Pulse Width.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Table 1- 1: Oscilloscope specifications (Cont.)

Pulse Width trigger

Pulse Width Range Selectablefrom33nsto10s

Pulse Width Resolution

Equal Guardband t > 330 ns: ±5% ≤ guardband < ±(5.1% + 16.5 ns)

Not Equal Guardband t > 330 ns: ±5% ≤ guardband < ±(5.1% + 16.5 ns)

Trigger frequency counter

Readout Resolution 6 digits

Accuracy (typical) ±51 parts per million including all frequency reference errors and ±1 count errors

Frequency Range AC coupled, 10 Hz minimum to rated bandwidth

Signal Source Pulse Width or Edge Trigger modes: all available trigger sources

16.5 ns or 1 part per thousand, whichever is larger

t ≤ 330 ns: guardband = ±16.5 ns

165 ns < t ≤ 330 ns: guardband = --16.5 ns/+33 ns

t ≤ 165 ns: guardband = ±16.5 ns

Specifications

The Frequency Counter measures trigger source at all times in Pulse Width or Edge modes, including when the oscilloscope acquisition is halted due to changes in the run status, or acquisition of a single shot event has completed.

Pulse Width Trigger mode: The oscilloscope counts pulses of significant magnitude inside the 250 ms measurement window that qualify as triggerable events, such as narrow pulses in a PWM pulse train if set to < mode and the width is set to a relatively small time.

Edge Trigger mode: The oscilloscope counts all edges of sufficient magnitude and correct pol ari ty.

Video Trigger mode: The Frequency Counter does not operate.

Measurements

Cursors Amplitude difference between cursors (ΔV, ΔA, ΔVA)

Time difference between cursors (Δt) Reciprocal of ΔtinHertz(1/Δt)

Automatic Measurements

Frequency, Period, Mean, Pk-Pk, Cycle RMS, Min, Max, Rise Time, Fall Time, Pos Width, N eg Width

TDS1000B and TDS2000B Series Oscilloscope Service Manual

1- 7

Specifications

gy,yp

Table 1- 2:

Oscilloscope general specifications

Display

Display Type 145 mm (5.7 in) diagonal liquid crystal

Display Resolution 320 horizontal by 240 vertical pixels

Display Contrast* Adjustable, temperature compensated

Backlight Intensity, typical Monochrome display Color display

75 cd/m

65 cd/m

Probe compensator output

Output Voltage, typical 5Vinto≥ 1MΩ load

Frequency, typical 1 kHz

Power Source

Source Voltage

100 -- 240 VAC

115 VA C

RMS

( 10%) 50/60 Hz ( 10%)

RMS

( 10%) 400 Hz ( 10%)

Power Consumption Less than 30 W

Fuse 1 A, T rating, 250 V

Environmental

Pollution Degree Pollution degree 2{, for indoor use only. Do not operate in an environment where conductive pollutants

may be present.

Temperature Operating 0 °Cto+50°C(32°F to 122 °F)

Non-Operating -- 4 0 °Cto+71°C(--40°F to 159.8 °F)

Cooling Method Convection

Humidity +40 °C or below

5% to 85% relative humidity

(+104 °F or below)

+41 °Cto+50°C

5% to 45% relative humidity

(106 °F to 122 °F)

>+50 °Cto+71°C

Wet bulb temperature of < 37 °C, which is 12% at +71 °C

(>122 °F to 160 °F)

Altitude 3,000 m (approximately 10,000 ft.)

Random Vibration Operating 0.31 g

Non-Operating 2.46 g

from 5 Hz to 500 Hz, 10 minutes on each axis

RMS

from 5 Hz to 500 Hz, 10 minutes on each axis

RMS

Mechanical Shock Operating 50 g, 11 ms, half sine

1- 8

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Specifications

Table 1- 2:

Mechanical

Size Height 158 mm (6.220 in)

Weight (approximate) Instrument only 2.0 kg (4.375 lbs)

* Adjustable through the Display menu.

{ As defined in IEC 61010--1:2001.

Oscilloscope general specifications (Cont.)

Width 326.3 mm (12.845 in)

Depth 124.1 mm (4.885 in)

TDS1000B and TDS2000B Series Oscilloscope Service Manual

1- 9

Specifications

1- 10

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Operating Information

For information on installing and operating your TDS1000B and TDS2000B Series Digital Storage Oscilloscope, refer to the TDS1000B and TDS2000B Series Digital Storage Oscilloscope User Manual. The user manuals are available in eleven languages and are on the Web at www.tektronix.com.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

2- 1

Operating Information

2- 2

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Theory of Operation

This chapter describes the electrical operation of the TDS1000B and TDS2000B series oscilloscopes to the module level. It describes the basic operation of each functional circuit block shown in Figures 3--1 and 3--2. Of necessity, the descriptions for the two and four channel units, and the color and monochrome units, are slightly different.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

3--1

Theory of Operation

AC Line

Power Supply

AC Line In

Backlight Power

Through

chassis

Front Panel

CH1

CH2

P53

Probe Comp

Signal

Probe Comp

GND

J300

J350

GND

J202

P/O J2031

P/O J2032

A1 Main

GND

USB Device

DC Out

&Line

Trigger

DC In

LCD

18 Pins

J902

port

J101

J201

P131

(Color)

PC or printer

(Mono)

TDS1000B (Mono) TDS2000B (Color)

Display

J90 1

Backlight

J902

Display Control

J380

EXT

TRIG

J901

Your USB Flash drive

USB Flash Drive port

Figure 3--1: Module-level block diagram (two channel)

3--2

TDS1000B and TDS2000B Series Oscilloscope Service Manual

AC Line

Theory of Operation

Power Supply

AC Line In

Backlight Power

Through

chassis

Front Panel

CH1

CH2

CH3

Probe Comp

Signal

Probe Comp

GND

A1 Main

GND

J202

J104 P/O J2031

J104 P/O J2032

J300

J350

J600

USB Device

DC Out

Trigger

DC In

LCD

18 Pins

J1202

port

&Line

J101

J201

PC or printer

Color Display

J90 1

Backlight

J902

Display Control

CH4

EXT

TRIG

Your USB Flash drive

J650

J680

J1201

USB Flash Drive port

Figure 3--2: Module-level block diagram (four channel)

TDS1000B and TDS2000B Series Oscilloscope Service Manual

3--3

Theory of Operation

Main Board

The Main board is also called the acquisition board. The Main board of the four-channel oscilloscopes is essentially 2, two-channel oscilloscopes tied together through a common microprocessor, and some special interconnects to support combining the display and trigger systems. For this reason, the focus of the main board discussion will be the two-channel system, with differences noted as necessary.

At a minimum, the main board contains attenuators, an amplifier ASIC, a digitizer/trigger system ASIC, a signal processing/display/system services ASIC, RAM, flash PROM, a system microprocessor, USB controller, USB RAM, system communication RAM, and special power supplies. For a four-channel oscilloscope, the attenuators and ASICs are duplicated. Most of the other aspects of the circuitry remain unchanged.

Acquisition System

Signals from the CH 1, CH 2 and other input connectors pass through attenuators and an AC-coupling switch to the amplifier ASIC. The EXT TRIG input has an abbreviated version of this path, lacking some of the attenuator settings and the AC coupling switch.

The amplifier ASIC contains buffers and variable gain amplifiers, as well as filters that provide 20 MHz bandwidth limiting. The task of the amplifier ASIC is to convert from a 1 MΩ single-ended environment in the front end to a much lower impedance differential (and thus less noise-sensitive) environment for the acquisition process. The amplifier ASIC assures that the input signal is amplified to approximately the correct level to allow the fullest possible use of the digitizer.

The acquisition ASIC contains samplers and peak detectors for each input channel, a common amplifier, an A/D converter, and the trigger logic. The digitized waveform samples are transferred to the processing and display ASIC. In four-channel systems, the two acquisition ASICs are interconnected so that a trigger on one ASIC can cause a trigger on the other.

The processor system adds the microprocessor and flash PROM to the processing and display system. The processor system interprets the front-panel control changes detected by the display ASIC, provides control parameters based upon user setting requests, computes waveform measurements, and manages the USB interfaces via the dedicated USB controller. Saved setups, waveforms, and calibration constants are stored in nonvolatile memory sections within the flash PROM. The processor system shares DRAM with the display system.

3--4

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Theory of Operation

Processing and Display

System

Input Signal Interface

The processing and display system consists of the display ASIC, DRAM, and system oscillator. Digitized acquisition samples are received by the display ASIC and stored in DRAM. Once data are received by the display ASIC, various corrections are applied, display rasterization is performed, and the waveform is placed into a display buffer. At the same time, the waveform is being read from the display buffers and written to the LCD. Additional circuitry in the display ASIC supports scanning the front panel, handling DRAM refresh, providing the processor clock, and performing various memory mapping tasks required by all elementary microprocessor based systems. In a four-channel system, the two display ASICs are interconnected so that one ASIC may provide display information for the second.

The processing and display system handles some of the computational tasks. Other tasks are performed by the processor system. Since all array processing is performed in the processing and display system, no computations can be performed that involve data from two different channel sets. Thus, subtracting channel 3 data from channel 2 is prohibited. Channel 1 and Channel 2 data may be combined in all of the supported ways.

BNC connectors are mounted on the main board for all signal inputs. The signal inputs are compatible with the supplied P2220 probes.

Probe Compensation

External Trigger

Main Board Power

The PROBE COMP and ground terminals are provided for probe adjustment.

The EXT TRIG channel is processed on the chain containing the highest numbered normal input channel.

To support various functions on the main board, a number of secondary power supplies are generated. For the amplifier and acquisition ASICs, the main board creates a +2.5 V and --2.5 V supply. The +2.5 V supply is derived from the +3.3 V logic supply. The --2.5 V supply is derived from the --4 V supply. One three terminal regulator provides +5 V for internal uses. A second three terminal regulator provides USB power to preclude USB faults from seriously disrupting operation of the oscilloscope.

An additional power supply provides the LCD bias voltage which ranges from +19 V to +28 V, depending on contrast setting and display type. This +28 V supply has a temperature sensor on the front-panel board that varies the output voltage of the supply to maintain contrast over a wide temperature range.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

3--5

Theory of Operation

Power Supply

Display Module

The main power supply module for the TDS1000B and TDS2000B series oscilloscopes is a wide input range universal supply. It is capable of providing about 25 W of power for the oscilloscope while allowing the input to run from about 90 V to 264 V. Input frequency ranges from 47 Hz to 440 Hz, which allows operation in virtually all countries in the world and in a number of off-grid environments, such as power on military aircraft.

The secondary supplies from the power supply and the approximate current draws are listed in the table on page 6--25 with the associated connector pins on J101.

For information on voltages used in the oscilloscope, refer to the Troubleshooting section of this manual.

Front Panel

Two-Channel

Oscilloscopes

The display module is a standard passive liquid crystal display (LCD). The monochrome unit is patterned with 320 columns by 240 rows, and has the associated drivers and backlight. The color unit is patterned with 320 columns x 3 sub-columns by 240 rows and has the associated drivers and backlight. In both displays, the backlight tube is in a 5mA top lamp configuration.

You can manipulate all of the switches, and position encoders on the front-panel board of two-channel oscilloscopes. Several LEDs are used to indicate when the Multipurpose knob is active, when Autorange is active, and when a Save action is in progress. For more information on the LEDs, refer to the User Manual for your oscilloscope.

Additionally, an IC on the front-panel board provides buffering and multiplexing of switch signals to the main board. Two signals and a sense line are provided by the main board to support the front panel. One of these lines resets the scan; a second clocks the scan to the next position; and the sense line receives the current state of the selected switch or encoder position.

For the encoders, some amount of debouncing occurs inside the front-panel IC. All key debouncing is handled in the display ASIC on the main board.

3--6

The LEDs are controlled by latching the value of the Channel 1--2 front panel scan counter when the appropriate scan value is set.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Theory of Operation

Four-Channel

Oscilloscopes

The front-panel board of the four channel units is effectively two panels in parallel. The left side of the board is largely handled by the display ASIC for channels 1 and 2. The right side of the board is handled by the channel 3 and 4 ASIC. Separate front-panel ICs support these data paths.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

3--7

Theory of Operation

3--8

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Performance Verification

OscilloscopeCalibration

This chapter contains performance verification procedures for the specifications marked with the n symbol. The following equipment, or a suitable equivalent, is required to complete these procedures.

Required Equipment

Description

DC Voltage Source 17.5mVto7V,±0.5%

Leveled Sine Wave Generator 50 kHz and 200 MHz, ±3%

Time Mark Generator 10 ms period, ±10 ppm

Minimum requirements

accuracy

amplitude accuracy

accuracy

Examples

Wavetek 9100 Universal Calibration System with Os

illoscopeCalibration

Module (Option 250)

Fluke 5500A Multi-product Calibrator with Oscilloscope Calibration Option (Option 5500A-SC)

50 Ω BNC Cable BNCmaletoBNCmale,

≈ 1 m (36 in) long

50 Ω BNC Cable BNCmaletoBNCmale,

≈ 25 cm (10 in) long

50 Ω Feedthrough Termination

Dual Banana to BNC Adapter Banana plugs to BNC female Tektronix part number

BNC T Adapter BNC male to dual BNC

Splitter, Power Frequency range: DC to

Adapter (four required) Male N-- to--female BNC Tektronix part number

Adapter Female N-- to--male BNC Tektronix part number

Leads, 3 Black Stacking Banana Plug Patch

Leads, 2 Red Stacking Banana Plug Patch

BNC male and female connectors

female connectors

4 GHz. Tracking: >2.0%

Cord, ≈ 45 cm (18 in) long

Tektronix part number 012-0482-XX

Tektronix part number 012-0208-XX

Tektronix part number 011-0049-XX

103-0090-XX

Tektronix part number 103-0030-XX

Tektronix part number 015-0565-XX

103-045-XX

103-0058-XX

Pomona #B-18-0

Pomona #B-18-2

TDS1000B and TDS2000B Series Oscilloscope Service Manual

4- 1

Performance Verification

Test Record

Model number

Serial number

Procedure performed by Date

Test Passed Failed

1. Self Test

2. Self Calibration

3. Oscilloscope tests

Oscilloscope tests Low limit Test result High limit

Channel 1 DC Gain Accuracy 5mV/div 33.6 mV 36.4 mV

200 mV/div 1.358 V 1.442 V

2V/div 13.58 V 14.42 V

Channel 2 DC Gain Accuracy 5mV/div 33.6 mV 36.4 mV

200 mV/div 1.358 V 1.442 V

2V/div 13.58 V 14.42 V

Channel 3 DC Gain Accuracy15mV/div 33.6 mV 36.4 mV

200 mV/div 1.358 V 1.442 V

2V/div 13.58 V 14.42 V

Channel 4 DC Gain Accuracy15mV/div 33.6 mV 36.4 mV

200 mV/div 1.358 V 1.442 V

2V/div 13.58 V 14.42 V

Channel 1 Bandwidth 2.12 V —

Channel 2 Bandwidth 2.12 V —

Channel 3 Bandwidth

Channel 4 Bandwidth

2.12 V —

Sample Rate and Delay Time Accuracy -- 2 d i v s +2 divs

Channel 1 Edge Trigger Sensitivity Stable trigger —

Channel 2 Edge Trigger Sensitivity Stable trigger —

Channel 3 Edge Trigger Sensitivity

Channel 4 Edge Trigger Sensitivity

Stable trigger —

External Edge Trigger Sensitivity Stable trigger —

4- 2

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Performance Verification

Oscilloscope tests High limitTest resultLow limit

Channel 1 Vertical Position Accuracy, Minimum margin 0 —

Channel 2 Vertical Position Accuracy, Minimum margin 0 —

Channel 3 Vertical Position Accuracy1, Minimum margin 0 —

Channel 4 Vertical Position Accuracy1, Minimum margin 0 —

Channels 3 and 4 are only available on four channel oscilloscopes.

The bandwidth test does not have a high limit.

The limits vary by model. Check the procedure for the correct limits.

Performance Verification Procedures

Before beginning these procedures, two conditions must first be met:

H The oscilloscope must have been operating continuously for twenty minutes

within the operating temperature range specified.

Self Test

Self Calibration

H You must perform the Self Calibration operation described below. If the

ambient temperature changes by more than 5 °C, you must perform the Self

Calibration operation again.

The time required to complete the entire procedure is approximately one hour.

WARNING. Some procedures use hazardous voltages. To prevent electrical shock, always set voltage source outputs to 0 V before making or changing any interconnections.

This internal procedure is automatically performed every time the oscilloscope is powered on. No test equipment or hookups are required. Verify that no error messages are displayed before continuing with this procedure.

The self calibration routine lets you quickly optimize the oscilloscope signal path for maximum measurement accuracy. You can run the routine at any time, but you should always run the routine if the ambient temperature changes by 5 _Cor more.

1. Disconnect any probes or cables from the channel input connectors (CH 1,

CH 2, CH 3, CH 4).

2. Push the UTILITY button and select the Do Self Cal option to start the

routine. The routine takes approximately one minute to complete.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

4- 3

Performance Verification

3. Verify that self calibration passed.

Check DC Gain Accuracy

This test checks the DC gain accuracy of all input channels.

1. Set the DC voltage source output level to 0V.

2. Set up the oscilloscope using the following steps:

Push menu button Select menu option Select setting

1. DEFAULT SETUP — —

2. CH 1 Probe 1X

3. ACQUIRE Average 16

4. MEASURE

Source Channel under test

Type Mean

3. As shown below, connect the oscilloscope channel selected in the table to the

DC voltage source.

DC voltage

source

Digitizing oscilloscope

+--

Dual banana to BNC adapter

BNC cable

4. For each VOL TS/DIV setting listed below, perform the following steps:

a. Set the DC voltage source output level to the positive voltage listed and

then record the mean measurement as V

pos

b. Reverse the polarity of the DC voltage source and then record the mean

measurement as V

c. Calculate V

diff=Vpos

neg

-- V

and then compare V

neg

to the accuracy

diff

limits in the table.

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TDS1000B and TDS2000B Series Oscilloscope Service Manual

Performance Verification

Check Bandwidth

VOLTS/DIV setting DC voltage source output levels Accuracy limits for V

5mV/div +17.5 mV, --17.5 mV 33.6 mV to 36.4 mV

200 mV/div +700 mV, --700 mV 1.358 V to 1.442 V

2V/div +7.00 V, --7.00 V 13.58 V to 14.42 V

5. Set DC voltage source output level to 0V.

6. Disconnect the test setup.

7. Repeat steps 1 through 6 until all input channels have been checked.

This test checks the bandwidth of all input channels.

1. Set up the oscilloscope using the following steps:

Push menu button Select menu option Select setting

DEFAULT SETUP — —

CH 1 Probe 1X

ACQUIRE Average 16

diff

TRIGGER Coupling Noise Reject

MEASURE

Source Channel under test

Type Pk-Pk

2. As shown below, connect the oscilloscope channel selected in the table to the

leveled sine wave generator.

Leveled sine wave generator

Output

BNC cable

Digitizing oscilloscope

50 Ω feedthrough terminator

3. Set the oscilloscope VOLTS/DIV to 500 mV/div.

4. Set the oscilloscope SEC/DIV to 10 s/div.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

4- 5

Performance Verification

5. Set the leveled sine wave generator frequency to 50 kHz.

6. Set the leveled sine wave generator output level so the peak-to-peak measurement is between 2.98 V and 3.02 V.

7. Set the leveled sine wave generator frequency to:

H 40 MHz if you are checking a TDS1001B

H 60 MHz if you are checking a TDS1002B, TDS2002B, or TDS2004B

H 100 MHz if you are checking a TDS1012B, TDS2012B, or TDS2014B

H 200 MHz if you are checking a TDS2022B, or TDS2024B

8. Set the oscilloscope SEC/DIV to 10 ns/div.

9. Check that the peak-to-peak measurement is ≥2.12 V.

10. Disconnect the test setup.

11. Repeat steps 1 through 10 until all input channels have been checked.

Check Sample Rate

Accuracy and Delay Time

Accuracy

This test checks the time base accuracy.

1. Set up the oscilloscope using the following steps:

Push menu button Select menu option Select setting

DEFAULT SETUP — —

CH 1 Probe 1X

2. Connect the oscilloscope to the time mark generator as shown below.

Time mark

generator

Output

BNC cable

Digitizing oscilloscope

50 Ω feedthrough terminator

4- 6

3. Set the time mark generator period to 10 ms.

4. Set the oscilloscope VOLTS/DIV to 500 mV/div.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Performance Verification

5. Set the oscilloscope Main SEC/DIV to 1ms/div.

6. Push SET TO 50%.

7. Use the vertical POSITION control to center the test signal on screen.

8. Use the horizontal POSITION control to set the position to 10.00 ms.

9. Set the oscilloscope SEC/DIV to 250 ns/div.

10. Check that the rising edge of the marker crosses the center horizontal

graticule line within ±2 divisions of the vertical center graticule line.

Vertical center graticule line

Horizontal center graticule line

Acceptable limits

NOTE. One division of displacement from graticule center corresponds to a 25 ppm time base error.

11. Disconnect the test setup.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

4- 7

Performance Verification

Check Edge Trigger

Sensitivity

This test checks the edge trigger sensitivity for all input channels.

1. Set up the oscilloscope using the following steps:

Push menu button Select menu option Select setting

DEFAULT SETUP — —

CH 1 Probe 1X

TRIGGER Mode Normal

ACQUIRE Sample —

MEASURE

Source Channel under test

Type Pk-Pk

2. As shown below, connect the oscilloscope channel selected in the table to the leveled sine wave generator.

Leveled sine

wave generator

Digitizing oscilloscope

Output

50 Ω feedthrough

BNC cable

terminator

3. Set the oscilloscope VOLTS/DIV to 500 mV/div.

4. Set the oscilloscope SEC/DIV to 25 ns/div.

5. Set the leveled sine wave generator frequency to 10 MHz.

6. Set the leveled sine wave generator output level to approximately 500 mV

so that the measured amplitude is approximately 500 mV. (The measured amplitude can fluctuate around 500 mV.)

7. Push SET TO 50%. Adjust TRIGGER LEVEL as necessary and then check that triggering is stable.

8. Set the leveled sine wave generator frequency to:

H 40 MHz if you are checking a TDS1001B

H 60 MHz if you are checking a TDS1002B, TDS2002B, or TDS2004B

p-p

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TDS1000B and TDS2000B Series Oscilloscope Service Manual

Performance Verification

H 100 MHz if you are checking a TDS1012B, TDS2012B, TDS2014B,

TDS2022B, or TDS2024B

9. Set the oscilloscope SEC/DIV to 5ns/div.

10. Set the leveled sine wave generator output level to approximately 750 mV

so that the measured amplitude is approximately 750 mV. (The measured amplitude can fluctuate around 750 mV.)

11. Push SET TO 50%. Adjust TRIGGER LEVEL as necessary and then

check that triggering is stable.

12. For the TDS2022B and TDS2024B models, set the frequency to 200 MHz,

and increase the amplitude to 1 Vp--p. Verify stable triggering.

13. Set the oscilloscope SEC/DIV to 2.5 ns/div.

14. Change the oscilloscope setup using the following step:

Push menu button Select menu option Select setting

TRIGGER Slope Falling

15. Push SET TO 50%. Adjust TRIGGER LEVEL as necessary and then

check that triggering is stable.

16. Disconnect the test setup.

17. Repeat steps 1 through 16 until all input channels have been checked.

p-p

Check External Edge

Trigger Sensitivity

This test checks the edge trigger sensitivity for the external trigger.

1. Set up the oscilloscope using the following steps:

Push menu button Select menu option Select setting

DEFAULT SETUP — —

CH 1 Probe 1X

TRIGGER

ACQUIRE Sample —

MEASURE

Source Ext

Mode Normal

Source CH1

Type Pk-Pk

TDS1000B and TDS2000B Series Oscilloscope Service Manual

4- 9

Performance Verification

2. Connect the oscilloscope to the leveled sine wave generator as shown below usingCH1andEXTTRIG.

Leveled sine

wave generator

Output

Power divider

Male SMA to female BNC

SMA female-to--female

Digitizing oscilloscope

3Pieces

50 Ω

feedthrough

terminator

3. Set the oscilloscope VOLTS/DIV to 100 mV/div.

4. Set the oscilloscope SEC/DIV to 25 ns/div.

5. Set the leveled sine wave generator frequency to 10 MHz.

6. Set the sine wave generator output level to approximately 300 mV

the power splitter. This will be about 200 mV

on CH1 of the oscilloscope.

p-p

EXT TRIG

into

p-p

The EXT TRIG input will also be receiving approximately 200 mV deviations from the nominal 200 mV

oscilloscope display are acceptable.

p--p

. Small

p-p

7. Set the leveled sine wave generator frequency to:

H 40 MHz if you are checking a TDS1001B

H 60 MHz if you are checking a TDS1002B, TDS2002B, or TDS2004B

H 100 MHz if you are checking a TDS1012B, TDS2012B, TDS2014B,

TDS2022B, or TDS2024B

8. Set the oscilloscope SEC/DIV to 5ns/div.

9. Push SET TO 50%. Adjust TRIGGER LEVEL as necessary and then

check that triggering is stable.

10. For TDS2022B and TDS2024B models, set the sine wave generator output level for a CH 1 display to approximately 350 mV

p-p

11. For TDS2022B and TDS2024B models, set the sine wave generator frequency to 200 MHz.

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TDS1000B and TDS2000B Series Oscilloscope Service Manual

Performance Verification

12. Set the oscilloscope SEC/DIV to 2.5 ns/div.

13. Push SET TO 50%. Adjust TRIGGER LEVEL as necessary and then

check that triggering is stable.

14. Change the oscilloscope setup using the following step:

Push menu button Select menu option Select setting

TRIGGER Slope Falling

15. Push SET TO 50%. Adjust TRIGGER LEVEL as necessary and then

check that triggering is stable.

16. Disconnect the test setup.

Check Vertical Position

Accuracy

The results of this test and the DC Gain Accuracy test together define the DC Measurement Accuracy of the oscilloscope. The DC Measurement Accuracy specification encompasses two different ranges of operation over two different attenuator settings:

H DC Gain Accuracy: Identifies errors, mostly from the A/D converter, when

the vertical position (known as offset in these oscilloscopes) is set to 0 divisions (or a grounded input will show screen center)

H Vertical Position Accuracy: Identifies errors, mostly from the position

control, made when the vertical position is set to a non--zero value

The two attenuator settings operate identically, so verification of the attenuation range from --1.8 V to 1.8 V also verifies the attenuation range of --45 V to 45 V.

To set up the test, follow these steps:

1. Set up the oscilloscope as shown in the next table.

Push menu button Select menu option Select setting

DEFAULT SETUP — —

CH 1, CH 2, CH 3, CH 4 Probe 1X

CH 1, CH 2, CH 3, CH 4 Volts/Div 50 mV/div

TRIGGER

ACQUIRE Sample —

Source Ext*

Mode Auto

TDS1000B and TDS2000B Series Oscilloscope Service Manual

4- 11

Performance Verification

Push menu button Select settingSelect menu option

MEASURE

The test operates without a trigger. To maintain uniformity and to avoid false triggering on noise, the Ext trigger is the recommended source.

Source Channel under test

Type Mean

2. Make a spreadsheet approximately as shown in the example in Appendix A. You only need to enter the values for column A and the equations. The values in columns B, C, D, E, F, and G are examples of the measured or calculated values.

The PDF version of the TDS1000B and TDS2000B service manual (which you can download from the www.tektronix.com Web site), includes an empty spreadsheet for your convenience. To access and save the test spreadsheet, see the instructions in Appendix A: Example of a Vertical Position Accuracy Test Spreadsheet on page A--1.

3. Connect the oscilloscope, power supply and voltmeter as shown next.

Oscilloscope under test

BNC-to-Dual

Banana adapter

Power supply

Negative

Red leads

Black leads

Voltmeter

4. Set the power supply to the 1.8 V value shown in column A, the Approximate Test Voltage.

5. Adjust the vertical position knob for the DC line to position the line in the center of the screen.

4- 12

6. Enter the voltage on the voltmeter and on the oscilloscope into the spreadsheet in the appropriate columns, B and C.

7. Repeat steps 4 through 6 for the values of 1.76 V through 0 V.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Performance Verification

8. Swap the connections to the positive terminal of the power supply with those

at the negative terminal as shown next.

Oscilloscope under test

BNC-to-Dual

Banana adapter

Power supply

Positive

Red leads

Black leads

Voltmeter

9. Repeat steps 4 through 6 for the values of --0.04 V through --1.8 V.

10. Enter the Minimum Margin number (cell I16) for the channel tested in the

test record.

11. Repeat steps 1 through 10 until all input channels have been checked.

Data Verification. To verify data, set the spreadsheet to present a line graph of columns D, E, and F. Verify that no error values (the blue line in the center) go above the yellow line (upper line), or below the purple line (lower line). For calculations involved in this example, refer to the data in the previous table.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

4- 13

Performance Verification

Measured Error

Measured Position

Figure 4- 1: Example of a line graph for the Vertical Position Accuracy test

Error

Lower limit

Upper limit

4- 14

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Adjustment Procedures

This chapter contains adjustment procedures for the TDS1000B and TDS2000B series oscilloscopes.

Only qualified personnel should perform service procedures. Read the Service Safety Summary and the General Safety Summary at the beginning of this manual before performing any service procedures. Also refer to the user manual for information about using the TDS1000B and TDS2000B oscilloscopes.

NOTE. The voltage references inside the TDS1000B and TDS2000B oscilloscopes are very stable over time and should not require routine updates. Before performing any procedure in this chapter, first verify that the oscilloscope does not meet specifications. Refer to the chapter Performance Verification to verify the specifications.

Required Equipment

The equipment described in Table 5--1, or a suitable equivalent, is required to complete these procedures.

Table 5--1: Required equipment

Description Minimum requirements Examples

DC Voltage Source -- 2 0 V t o 2 0 V, ±0.1% accuracy Wavetek 9100 Universal Calibration

System with Oscilloscope Calibration Module (Option 250)

Leveled Sinewave Generator

50 Ω BNC Cable

50 Ω BNC Cable (seven)

50 Ω Feedthrough Termination

5 kHz and 200 MHz, ±0.6% amplitude accuracy

BNCmaletoBNCmale, ≈ 1 m (36 in) long

BNCmaletoBNCmale, ≈ 25 cm (10 in) long

BNC male and female connectors

Fluke 5500A Multi-product Calibrator with Oscilloscope Calibration Option (Option 5500A-SC)

Tektronix part number 012-0482-XX

Tektronix part number 012-0208-XX

Tektronix part number 011-0049-XX

TDS1000B and TDS2000B Series Oscilloscope Service Manual

5--1

Adjustment Procedures

Table 5--1: Required equipment (Cont.)

Description ExamplesMinimum requirements

Dual Banana to BNC Adapter

Banana plugs to BNC female Tektronix part number 103-0090-XX

Adjustment Procedure

BNC T (three) One male and two female

BNC connectors

Tektronix part number 103-0030-XX

The adjustment procedure consists of 70 steps for the two-channel oscilloscope, and 106 steps for the four-channel model. Each step requires an external voltage source for new calibration constants.

Before performing the adjustment procedure, warm up the oscilloscope for at least ten minutes in an ambient temperature between 20 °C and 30 °C. Adjustments performed prior to warm-up or outside this temperature range may result in poor performance.

If all steps in the procedure are completed successfully, a “Pass” message is displayed and the new calibration constants take affect. If any step fails, the procedure is aborted and the current calibration is not affected. You can choose to abort the procedure at any step, without affecting the current calibration, by selecting FCAL ABORT.

NOTE. While performing the adjustment procedure, keep in mind that some of the steps take a significant amount of time (up to 5 minutes) to complete.

Enable the Service Menu

5--2

The equipment setups, shown in Figure 5--1, are required to complete the adjustment procedure. Table 5--2 on page 5--6 lists the steps in the procedure and the signal requirement for each step.

You must enable the Service menu to perform the adjustment procedure. To do this:

1. Power on the oscilloscope.

2. Push the front-panel MEASURE button to access the MEASURE menu.

3. Push the top option button to access the Measure 1 menu.

4. Push and hold the front-panel SINGLE SEQ button.

5. Push and hold the front-panel AUTOSET button.

6. Wait at least two seconds.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Adjustment Procedures

7. Release the SINGLE SEQ button.

8. Release the AUTOSET button. A message appears in the lower left corner of

the screen stating “Service mode ON.”

9. Push the front-panel UTILITY button. The last item in the Utility menu is now “Service.”

At completion of the Adjust procedure disable the “Service” menu through the UTILITY front panel button, the “Service” option button, and the “Service” Mode Off” option button.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

5--3

Adjustment Procedures

DC voltage setup 1

DC voltage source

+--

Dual banana to BNC adapter

10-inch BNC cable

Two Channel

Digitizing oscilloscope

10-inch

BNC cables

BNC ‘T’ connector

Four Channel

Digitizing oscilloscope

10-inch

BNC cables

10-inch

BNC cable

BNC ‘T’ connector

10-inch BNC cable

10-inch

BNC cables

BNC ‘T’

connectors

DC voltage setup 2

Sinewave generator setup

Leveled sine

wave generator

Output

50 Ω feedthrough terminator

(Table 5--2 and 5--3 list

DC voltage source

+--

Two Channel

Digitizing oscilloscope

proper channel)

Dual banana to BNC adapter

Two Channel

Digitizing oscilloscope

1 M BNC cable

Edge setup

Square wave

generator

Four Channel

Digitizing oscilloscope

Output

50 Ω feedthrough terminator

(Table 5--2 and 5--3 list

proper channel)

1 M BNC cable

Figure 5--1: Adjustment setups

5--4

1 M BNC cable

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Adjustment Procedures

Adjustment Procedure

Use this procedure to load new calibration constants.

1. Enable the Service menu as described on page 5--2.

2. Push the Service option button.

3. Push the Factory Cal option button.

4. Push the Warmup Timer option button.

5. Push the Start Timer option button to ensure a 10-minute warm up. After 10

minutes pass, the oscilloscope displays a large black or green cross.

6. Press the front-panel UTILITY button and push the Service option button.

7. Push the Factory Cal option button.

8. Push the FCAL INIT option button to initiate the factory calibration routine.

You are now in step 1 of the procedure.

9. As indicated by Step 1 in Table 5--2, connect a 0.0 V

source to the channel

inputs.

10. Press FCAL STEP to load the calibration constant for step 1.

11. Follow the screen prompts along with Table 5--2 for the remainder of the

routine, applying the proper signal for each step.

NOTE. During some steps, the oscilloscope may appear to be idle for several minutes while it is processing information internally. You must wait for the screen prompt to continue.

If any step in the procedure fails, the procedure terminates. Failure will result if an incorrect signal source is connected. If this happens, you must start the procedure over from the beginning.

If the procedure completes successfully, a “Pass” message is displayed and the new adjustment takes effect.

12. Compensate the signal path by performing the self-calibration routine. Disconnect any probes or cables from the channel input connectors. Then, press the UTILITY button and select Do Self Cal to confirm that you are ready to proceed.

13. Disable the Service menu option by pushing the UTILITY front-panel button, and the Service and Service Mode Off option buttons.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

5--5

Adjustment Procedures

Table 5--2: Adjustment steps

Step number (Two-channel models)

Refer to the DC voltage setup 1 diagram

1 1 DC Voltage 1 0.0 V

2 2 DC Voltage 1 --20.0 V

3 3 DC Voltage 1 -- 2 . 0 V

4 4 DC Voltage 1 -- 1 . 6 V

5 5 DC Voltage 1 -- 1 . 2 V

6 6 DC Voltage 1 -- 0 . 8 V

7 7 DC Voltage 1 -- 0 . 4 V

8 8 DC Voltage 1 --0.32 V

9 9 DC Voltage 1 -- 0 . 2 V

10 10 DC Voltage 1 --0.16 V

11 11 DC Voltage 1 --0.08 V

12 12 DC Voltage 1 --0.04 V

13 13 DC Voltage 1 --0.03 V

14 14 DC Voltage 1 --0.02 V

15 15 DC Voltage 1 --0.015 V

16 16 DC Voltage 1 0.015 V

17 17 DC Voltage 1 0.02 V

18 18 DC Voltage 1 0.03 V

19 19 DC Voltage 1 0.04 V

20 20 DC Voltage 1 0.08 V

21 21 DC Voltage 1 0.16 V

22 22 DC Voltage 1 0.2 V

23 23 DC Voltage 1 0.32 V

24 24 DC Voltage 1 0.4 V

25 25 DC Voltage 1 0.8 V

26 26 DC Voltage 1 1.2 V

27 27 DC Voltage 1 1.6 V

28 28 DC Voltage 1 2.0 V

29 29 DC Voltage 1 20.0 V

30 30 DC Voltage 1 0.0 V

Step number (Four-channel models)

Signal Signal source setting Input

CH1 through CHx

5--6

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Table 5--2: Adjustment steps (Cont.)

hmBWL

5050SinewaveGenerator,50OhmBW

L,2.5

p-p

5151SinewaveGenerator,50OhmBW

L,5

p-p

Adjustment Procedures

Step number (Two-channel models)

Step number (Four-channel models)

Refer to the DC voltage setup 2 diagram

31 31 DC Voltage 2 -- 5 . 0 V

32 32 DC Voltage 2 -- 1 . 0 V

33 33 DC Voltage 2 1.0 V

34 34 DC Voltage 2 5.0 V

Refer to the Sinewave generator setup diagram. BWL refers to the maximum bandwidth of the oscilloscope.

35 35 Sinewave Generator, 50 Ohm 5 kHz, 1 V

36 36 Sinewave Generator, 50 Ohm 1 MHz, 100 mV

37 37 Sinewave Generator, 50 Ohm 1MHz,1V

38 38 Sinewave Generator, 50 Ohm 50 kHz, 1 V

39 39 Sinewave Generator, 50 Ohm 20 MHz, 1 V

40 40

newaveGenerator, 50

41 41 Sinewave Generator, 50 Ohm BWL, 50 mV

42 42 Sinewave Generator, 50 Ohm BWL, 100 mV

43 43 Sinewave Generator, 50 Ohm BWL, 250 mV

44 44 Sinewave Generator, 50 Ohm BWL, 500 mV

45 40 Sinewave Generator, 50 Ohm BWL, 1 V

46 46 Sinewave Generator, 50 Ohm 5 kHz, 2.5 V

47 47 Sinewave Generator, 50 Ohm 1MHz,2.5V

48 48 Sinewave Generator, 50 Ohm 50 kHz, 2.5 V

49 49 Sinewave Generator, 50 Ohm 20 MHz, 2.5 V

,25m

p-p

InputSignal source settingSignal

EXT TRIG

CH1

52 52 Sinewave Generator, 50 Ohm BWL, 1.6 V

53 53 Edge, 50 Ohm. Refer to Edge setup

1 kHz, 0 to --800 mV

p-p

diagram.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

5--7

Adjustment Procedures

hmBWL

6969SinewaveGenerator,50OhmBW

L,2.5

p-p

7070SinewaveGenerator,50OhmBW

L,5

p-p

Table 5--2: Adjustment steps (Cont.)

Step number (Two-channel models)

54 54 Sinewave Generator, 50 Ohm 5 kHz, 1 V

Step number (Four-channel models)

p-p

55 55 Sinewave Generator, 50 Ohm 1 MHz, 100 mV

56 56 Sinewave Generator, 50 Ohm 1MHz,1V

57 57 Sinewave Generator, 50 Ohm 50 kHz, 1 V

58 58 Sinewave Generator, 50 Ohm 20 MHz, 1 V

59 59

newaveGenerator, 50

60 60 Sinewave Generator, 50 Ohm BWL, 50 mV

,25m

p-p

61 61 Sinewave Generator, 50 Ohm BWL, 100 mV

62 62 Sinewave Generator, 50 Ohm BWL, 250 mV

63 63 Sinewave Generator, 50 Ohm BWL, 500 mV

64 64 Sinewave Generator, 50 Ohm BWL, 1 V

65 65 Sinewave Generator, 50 Ohm 5 kHz, 2.5 V

66 66 Sinewave Generator, 50 Ohm 1MHz,2.5V

p-p

67 67 Sinewave Generator, 50 Ohm 50 kHz, 2.5 V

68 68 Sinewave Generator, 50 Ohm 20 MHz, 2.5 V

InputSignal source settingSignal

CH2

p-p

5--8

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Table 5--2: Adjustment steps (Cont.)

hmBWL

86SinewaveGenerator,50OhmBW

L,2.5

p-p

87SinewaveGenerator,50OhmBW

L,5

p-p

Adjustment Procedures

Step number (Two-channel models)

Step number (Four-channel models)

71 Sinewave Generator, 50 Ohm 5 kHz, 1 V

p-p

72 Sinewave Generator, 50 Ohm 1 MHz, 100 mV

73 Sinewave Generator, 50 Ohm 1MHz,1V

74 Sinewave Generator, 50 Ohm 50 kHz, 1 V

75 Sinewave Generator, 50 Ohm 20 MHz, 1 V

newaveGenerator, 50

77 Sinewave Generator, 50 Ohm BWL, 50 mV

,25m

p-p

78 Sinewave Generator, 50 Ohm BWL, 100 mV

79 Sinewave Generator, 50 Ohm BWL, 250 mV

80 Sinewave Generator, 50 Ohm BWL, 500 mV

81 Sinewave Generator, 50 Ohm BWL, 1 V

82 Sinewave Generator, 50 Ohm 5 kHz, 2.5 V

83 Sinewave Generator, 50 Ohm 1MHz,2.5V

p-p

84 Sinewave Generator, 50 Ohm 50 kHz, 2.5 V

85 Sinewave Generator, 50 Ohm 20 MHz, 2.5 V

InputSignal source settingSignal

CH3

p-p

88 Sinewave Generator, 50 Ohm BWL, 1.6 V

89 Edge, 50 Ohm. Refer to the Edge

1 kHz, 0 to --800 mV

setup diagram.

p-p

TDS1000B and TDS2000B Series Oscilloscope Service Manual

5--9

Adjustment Procedures

hmBWL

p-p

105SinewaveGenerato

r,50OhmBW

L,2.5

p-p

L,5V

p-p

106SinewaveGenerato

r,50OhmBW

L,5

p-p

Table 5--2: Adjustment steps (Cont.)

Step number (Two-channel models)

Step number (Four-channel models)

90 Sinewave Generator, 50 Ohm 5 kHz, 1 V

p-p

91 Sinewave Generator, 50 Ohm 1 MHz, 100 mV

92 Sinewave Generator, 50 Ohm 1MHz,1V

93 Sinewave Generator, 50 Ohm 50 kHz, 1 V

94 Sinewave Generator, 50 Ohm 20 MHz, 1 V

newaveGenerator, 50

96 Sinewave Generator, 50 Ohm BWL, 50 mV

,25m

p-p

97 Sinewave Generator, 50 Ohm BWL, 100 mV

98 Sinewave Generator, 50 Ohm BWL, 250 mV

99 Sinewave Generator, 50 Ohm BWL, 500 mV

100 Sinewave Generator, 50 Ohm BWL, 1 V

101 Sinewave Generator, 50 Ohm 5 kHz, 2.5 V

102 Sinewave Generator, 50 Ohm 1MHz,2.5V

p-p

103 Sinewave Generator, 50 Ohm 50 kHz, 2.5 V

InputSignal source settingSignal

CH4

p-p

104 Sinewave Generator, 50 Ohm 20 MHz, 2.5 V

105 Sinewave Generator, 50 Ohm B

,2.5

106 Sinewave Generator, 50 Ohm B

p-p

5--10

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

Preventing ESD

This chapter contains the information needed to do periodic and corrective maintenance on the oscilloscope, as well as repackaging instructions if you need to return the oscilloscope to Tektronix for service.

Before servicing this product, read the Safety Summary and Introduction at the front of the manual and the electrostatic discharge (ESD) information below.

CAUTION. Static discharge can damage any semiconductor component in this oscilloscope.

When performing any service which requires internal access to the oscilloscope, adhere to the following precautions. These precautions help you avoid damaging internal modules and their components due to electrostatic discharge (ESD).

H Minimize handling of static-sensitive modules.

H Transport and store static-sensitive modules in their static protected

containers or on a metal rail. Label any package that contains static-sensitive modules.

H Discharge the static voltage from your body by wearing a grounded antistatic

wrist strap while handling these modules.

H Service static-sensitive modules only at static-free workstations. Do not

allow anything capable of generating or holding a static charge on the workstation surface.

H Handle circuit boards by the edges when possible.

H Do not slide the modules over any surface.

H Avoid handling modules in areas that have a floor or work-surface covering

capable of generating a static charge.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--1

Maintenance

Inspection and Cleaning

Inspection and cleaning are done as preventive maintenance. Preventive maintenance, when done regularly, may prevent oscilloscope malfunction and enhance its reliability.

Preventive maintenance consists of visually inspecting and cleaning the oscilloscope, and using general care when operating it. How often you do maintenance depends on the severity of the environment in which you use the oscilloscope. A good time to perform preventive maintenance is just before adjustment of the oscilloscope.

General Care

Interior Cleaning

For optimum performance, follow these recommendations:

H Protect the oscilloscope from adverse weather conditions. The oscilloscope is

not waterproof.

H Do not store or leave the oscilloscope where the liquid crystal display (LCD)

will be exposed to direct sunlight or high humidity for long periods of time.

H The front and rear cases help keep dust out of the oscilloscope and must be in

place during normal operation.

H To avoid damage to the oscilloscope or probes, do not expose them to any

sprays, liquids, or solvents.

Use a dry, low-velocity stream of air to clean the interior of the chassis. Use a soft-bristle, non-static-producing brush for cleaning around components. If you must use a liquid for minor interior cleaning, use a 75% isopropyl alcohol solution and rinse with deionized water.

WARNING. To avoid injury, power down the instrument and disconnect it from line voltage before performing any procedure that follows.

6--2

Exterior Cleaning

Clean the exterior surfaces of the chassis with a dry lint-free cloth or a softbristle brush. If any dirt remains, use a cloth or swab dipped in a 75% isopropyl alcohol solution. Use a swab to clean narrow spaces around controls and connectors. Do not use abrasive compounds on any part of the chassis that may damage the chassis.

Clean the On/Standby switch using a dampened cleaning towel. Do not spray or wet the switch directly.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

CAUTION. Avoid the use of chemical cleaning agents, which might damage the plastics used in this oscilloscope. Use only deionized water when cleaning the menu buttons or front-panel buttons. Use a 75% isopropyl alcohol solution as a cleaner and rinse with deionized water. Before using any other type of cleaner, consult your Tektronix Service Center or representative.

Exterior Inspection

Inspect the outside of the oscilloscope for damage, wear, and missing parts, using Table 6--1 as a guide. Immediately repair defects that could cause personal injury or lead to further damage to the oscilloscope.

Table 6--1: External inspection check list

Item Inspect for Repair action

Front and rear case Cracks, scratches, deformations,

damaged hardware

Front-panel knobs Missing, damaged, or loose

knobs

Connectors Broken shells, cracked insulation,

and deformed contacts. Dirt in connectors

Carrying handle, and cabinet feet

Accessories Missing items or parts of items,

Correct operation Repair or replace defective

bent pins, broken or frayed cables, and damaged connectors

Repair or replace defective module

Repair or replace missing or defective knobs

Repair or replace defective modules. Clear or wash out dirt.

module

Repair or replace damaged or missing items, frayed cables, and defective modules

If the display is very dirty, moisten the wipe with distilled water or a 75% isopropyl alcohol solution and gently rub the display surface. Avoid using excess force or you may damage the plastic display surface.

CAUTION. To prevent getting moisture inside the oscilloscope during external cleaning, use only enough liquid to dampen the cloth or applicator.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--3

Maintenance

Interior Inspection

To access the inside of the oscilloscope for inspection and cleaning, refer to the Removal Procedures in this section.

Use Table 6--2 as a guide to inspect the internal portions of the oscilloscope for damage and wear. Repair any defects immediately.

If any circuit board is repaired or replaced, check Table 6--2 to see if it is necessary to adjust the oscilloscope.

CAUTION. To prevent damage from electrical arcing, ensure that circuit boards and components are dry before applying power to the oscilloscope.

Table 6--2: Internal inspection check list

Item Inspect for Repair action

Circuit boards Loose, broken, or corroded solder

connections. Burned circuit boards. Burned, broken, or cracked circuit-run plating.

Resistors Burned, cracked, broken, blis-

tered condition.

Solder connections Cold solder or rosin joints. Resolder joint and clean with

Remove and replace damaged circuit board.

isopropyl alcohol.

Capacitors Damaged or leaking cases.

Corroded solder on leads or terminals.

Wiring and cables Loose plugs or connectors.

Burned, broken, or frayed wiring.

Chassis Dents, deformations, and dam-

aged hardware.

Remove and replace damaged circuit board.

Firmly seat connectors. Repair or replace modules with defective wires or cables.

Straighten, repair, or replace defective hardware.

Cleaning Procedure, Interior. To clean the oscilloscope interior, perform the following steps:

1. Blow off dust with dry, low-pressure, deionized air (approximately 9 psi).

2. Remove any remaining dust with a lint-free cloth dampened in isopropyl

alcohol (75% solution) and then wipe with a lint-free cloth dampened with warm deionized water. A cotton-tipped applicator is useful for cleaning in narrow spaces and on circuit boards.

6--4

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

STOP. If, after performing steps 1 and 2, a module is clean upon inspection, skip steps 3, 4, and 5. Proceed with step 6.

3. If steps 1 and 2 do not remove all the dust or dirt, all modules in the oscilloscope except the Display Module and Front Panel Module may be spray washed using a solution of 75% isopropyl alcohol.

H During cleaning of the Acquisition board (main board), use care to

assure that no residue is left in the attenuators. Debris or residue can cause a number of problems with signal fidelity that cannot be corrected by calibration. When handling the board, avoid handling the attenuators since skin oils may cause problems.

H Extensive cleaning of the Display Module is difficult because water must

not be trapped between the display shield and the display. The polarizers integrated into the display degrade with long-term exposure to water. The display shield and display must be replaced as an assembly if significant moisture or debris become trapped inside. Cotton tipped applicators and lint-free rags moistened in isopropyl alcohol and/or deionized water offer the best cleaning with the least opportunity for damage to the assembly.

H The Front Panel module can be damaged by deposition of film or debris

inside the knob encoders. To avoid this, care must be taken to not drip liquid or blow debris into the encoders.

4. Spray wash dirty parts with the 75% isopropyl alcohol solution and wait 60 seconds for the majority of the alcohol to evaporate.

5. Use hot (49 _Cto60_C / 120 _F to 140 _F) deionized water to thoroughly rinse the parts.

6. Dry all parts with low-pressure, deionized air.

7. Dry all components and assemblies in an oven or drying compartment using

low-temperature (52 _Cto66_C / 125 _F to 150 _F) circulating air.

Lubrication. Periodic lubrication is not required for the oscilloscope.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--5

Maintenance

Removal and Installation Procedures

Refer to Figures 6--1 and 6--2 for the location of modules that you are removing or installing. If you are disassembling the instrument for cleaning, refer to the Inspection and Cleaning procedure on page 6--2 for instructions.

List of Modules

Summary of Procedures

The Replaceable Parts List provides a list of all replaceable modules. Any replaceable component, assembly, or part is referred to by the term module.

WARNING. Only qualified personnel should perform service procedures. Before doing this or any other procedure in this manual, read the General Safety Summary and Service Safety Summary found at the beginning of this manual. To prevent damage to electrical components, read Preventing ESD on page 6-- 1.

Always disconnect the power cord before disassembling any portion of the oscilloscope.

Complete disassembly is best achieved by following the procedures in the order given in Table 6--3.

Table 6--3: List of procedures

Procedure Begins on page

Rear Feet 6--8

Flip Feet 6--8

6--6

Front-Panel Knobs and Power Button 6--9

Rear Case 6--9

Front Feet 6--10

Power Supply Module 6--11

Internal Assembly 6--12

Display Cable 6--12

Front-Panel Cable 6--14

Main Board Module 6--15

Color Display Module 6--16

Monochrome Display Module 6--16

Front-Panel Module 6--18

Keypad 6--18

Front Case 6--19

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Front Case

assembly

Maintenance

Power button

Rear case

Rear foot

Front foot

Figure 6--1: Locator for trim and cabinet removal

Display

assembly

Switch keypad

Power supply

assembly

Front panel assembly

Front flip foot

Main board

assembly

Chassis assembly

Figure 6--2: Locator for internal modules

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--7

Maintenance

Required Tools

Rear Feet

Use the following tools to remove and replace all modules in the oscilloscope:

H Torque-limiting screwdriver, long shank, 12 in-lb (1.3 N

⋅m) range with

Torx® T-15 tip; if you use a magnetic screwdriver with interchangeable bits, the T--15 bit must be a long bit, at least 5 cm (2 in) overall length

H Torque-limiting screwdriver with Torx T--8 bit

H 5/8 inch deep socket with wide center hole (S

⋅K Hand Tool Corp., S-K

#40820, or equivalent)

H Torque wrench to 40 in-lb (4.5 N

⋅m)

H Screwdriver with 1/4 inch flat blade

H Pliers (all-purpose and needle-nose)

H Sharp knife (X-ACTO

® knife or equivalent)

H 3M Electrical Tape 92 with 1--mil polyimide Kapton backing, temperature

rated 180 °C, UL510 Flame Retarded

You will need a flat-blade screwdriver to remove the rear feet.

Flip Feet

Removal. To remove the rear feet, refer to Figure 8--4 and follow these steps:

1. Place the oscilloscope face down on a soft surface such as an anti-static mat.

2. Use a flat-blade screwdriver to pry out the foot, or twist the foot as you are

removing it so that it disengages from the guides. Use care not to mar the surface of the rear case.

Installation. To install the rear feet, refer to Figure 8--4 and follow these steps:

1. Place the oscilloscope face down on a soft surface such as an anti-static mat.

2. Align the slots of the rear foot with the guides in the rear case and press the

foot in.

You will need a pair of needle-nose pliers to remove the flip feet.

Removal. To remove the flip feet, refer to Figure 8--4 and follow these steps:

1. Place the oscilloscope face down on a soft surface such as an anti-static mat.

2. Grip the flip foot with the pliers as close to the notches as possible and

squeeze gently on the foot.

6--8

3. Twist slightly to swing one hinge free of the slot.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

Installation. To install the flip feet, refer to Figure 8--4, and follow these steps:

1. Place the oscilloscope face down on a soft surface such as an anti-static mat.

2. Hold the flip foot with the smooth side facing down.

3. Gently squeeze the foot so that the hinge on one side fits into the slot, and

twist slightly to snap into the slot on the other side.

Front-Panel Knobs

Power Button

Rear Case

Remove each front-panel knob by firmly grasping the knob (with pliers if necessary) and pulling it away from the front panel.

NOTE. Wrap the plier jaws with tape (such as electrical) to avoid marring the knob surface.

Install front-panel knobs by aligning the keyed knob with the shaft and pressing the knob onto the shaft.

Remove the power button by firmly grasping the button with pliers, and pull it straight out of the cabinet.

NOTE. Wrap the plier jaws with tape (such as electrical) to avoid marring the button surface.

Install the button by pressing it onto the power button shaft until it snaps into place.

You will need a torque-limiting Torx T-15 screwdriver and pliers for this procedure.

Removal. To remove the rear case, refer to Figure 8--4, and follow these steps:

1. Remove the power button using the procedure on page 6--9.

2. Place the oscilloscope face down on a soft surface such as an anti-static mat.

3. Remove the five screws located on the rear case. Tilt the handle to gain better

access to the top two screws.

4. Lift the rear case off of the oscilloscope.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--9

Maintenance

Installation. Use this procedure to install the rear case.

1. Place the oscilloscope face down on a soft surface (such as an anti-static mat).

2. Place the rear case onto the assembled oscilloscope and ensure that:

H All of the edges align with the front case.

H The Li--ION battery is vertical in the battery location.

H The slots align near the USB connector and near the battery.

CAUTION. Be careful not to pinch any wires or other parts between the front and rear cases.

3. Install the five screws in the rear case. Tilt the handle to better access the top two holes.

Front Feet

CAUTION. Avoid cross threading the screws that secure the rear case to the front case. An easy way to avoid this is to slip the screw into the hole and, using slight pressure, slowly rotate the screw counterclockwise until you feel the screw slip into the screw threads. Then tighten the screw clockwise. A properly s tarted screw will have very little resistance going in.

4. Install the power button as described on page 6--9.

You will need a torque-limiting Torx T-15 screwdriver and pliers for this procedure.

Removal. First, remove the power button and rear case using the procedures on page 6--9. Then, slide the front feet out of the front case as shown in Figure 8--1 for 2-channel models, or Figure 8--2 for 4-channel models.

Installation. Slide the feet into the slots provided in the front case as shown in Figure 8--1 for 2-channel models, or Figure 8--2 for 4-channel models. Use the installation procedures for each module removed to reassemble the oscilloscope.

NOTE. If the front feet are not installed, but are available, they can be inserted by carefully pinching them and pushing them into their slots. For example, you may need to do this if the rear case has been removed, and a foot has been rubbed off and unnoticed until the case is being reassembled.

6--10

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

Power Supply Module

Use a torque-limiting Torx T-15 screwdriver and pliers for this procedure.

Removal. To remove the module, refer to Figure 8--3 and follow these steps:

1. Remove the power button and rear case using the procedures on page 6-- 9.

2. Disconnect the following wires:

H The ground wire on the power supply module from the chassis ground

lug.

H The two-conductor backlight cable on the power supply module.

H The power supply cable on the main board at J101. Press down on the

latch while pulling up on the cable.

3. Remove the five screws connecting the power supply module to the chassis and lift the module from the internal assembly.

Installation. To install the power supply module, refer to Figure 8--3 and follow these steps:

1. Align and place the power supply module into the internal assembly.

2. Install the two longer screws with thread lock into the IEC connector

mounting holes.

3. Install the three shorter screws through the power supply and into the chassis.

4. Reconnect the following wire and cables:

H The ground wire on the power supply module to the chassis ground lug.

You may need to use pliers to secure the wire in place.

H The two-conductor backlight cable to the power supply module.

H The power supply cable to the main board at J101. Twist the cable to

keep it from contact with the boards and chassis.

NOTE. Wind up the power supply cable until it is tight; loops are okay. This keeps the cable bundle together.

5. Use the installation procedure for each module removed to reassemble the oscilloscope.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--11

Maintenance

Internal Assembly

You will need a torque-limiting Torx T-15 screwdriver and a pair of pliers for this procedure.

Removal. To remove the internal assembly, refer to Figure 8--4 and follow these steps:

1. Remove the front-panel knobs, power button, and rear case using the procedures on page 6--9.

2. Remove the five screws attaching the internal assembly to the front case.

3. Lift the entire internal assembly (consisting of the chassis, all of the boards,

and the display screen) out of the front case.

NOTE. The switch keypad will most likely remain inside the front case. It does not need to be removed with the internal assembly.

Installation. To install the internal assembly, refer to Figure 8--4 and follow these steps:

1. Use the installation procedure for each module removed to reassemble the oscilloscope.

Display Cable

2. Install the switch mat in the front case.

3. Place the internal assembly into the front case.

4. Install the five screws to attach the internal assembly to the front case.

You will need a torque-limiting Torx T-15 screwdriver and pliers for this procedure.

Removal. To remove the display cable, refer to Figure 8--3 and follow these steps:

1. Remove the power button and rear case using the procedures on page 6-- 9.

2. Remove the power supply using the procedure on page 6--11.

3. Disconnect the display cable at J201 on the main board by pulling straight up

from the connector.

4. Remove the cable tie, and remove the tape to release the display cable.

6--12

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

5. Remove the display.

6. Disconnect the display cable on the display module.

7. Thread the cable out of the chassis.

Installation. To install the display cable, refer to Figure 8--3 and follow these steps:

1. Remove the display module using the procedure on page 6--16.

2. Attach the display cable to the appropriate connector on the display module

at the location shown in Figure 8--3: 12-pin for the monochrome display, and 15-pin for the color display.

3. With the display module in place but not connected, thread the display cable through the appropriate slot on the chassis.

4. Twist the cable to keep it from contact with the boards and chassis.

NOTE. Wind up the display cable until it is tight; loops are okay. This keeps the cable bundle together.

5. Connect the display cable at J201 on the main board by pushing the cable straight down into the connector.

6. Secure the display cable to the chassis with the cable tie.

7. Apply 3 strips of 3M Electrical Tape 92 to secure the cable to the chassis.

Figure 6--3 shows where to apply the tape for good results.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--13

Maintenance

Twist the display cable

Addacabletie

Tape the cable to the chassis

Front-Panel Cable

Figure 6--3: Securing the display cable to the chassis

8. Install the four screws to attach the display module to the internal assembly.

You will need a torque-limiting Torx T-15 screwdriver and pliers for this procedure.

Removal. To remove the front-panel cable, refer to Figure 8--3 and follow these steps:

1. Remove the front-panel knobs, power button, and rear case using the procedures on page 6--9.

2. Remove the internal assembly using the procedure on page 6--12.

3. Remove the five screws attaching the front panel board to the chassis.

4. Untwist the cable tie to release the front-panel cable.

5. Disconnect the front-panel cable at J202 on the main board by pulling

straight up from the connector.

6. Disconnect the front-panel cable at J1 on the front-panel module.

6--14

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

Installation. To install the front-panel cable, refer to Figure 8--3 and follow these steps:

1. Connect the front-panel cable to the front-panel module at J1 through the appropriate slot on the chassis.

2. Twist the cable to keep it from contact with the boards and chassis, and secure using the right cable tie.

NOTE. Wind up the front-panel cable until it is tight; loops are okay. This keeps the cable bundle together.

3. Connect the front-panel cable at J202 on the main board by pushing the cable straight down into the connector.

4. Install the five screws to attach the front panel module to the chassis.

Main Board Module

You will need a torque-limiting Torx T-15 long shank screwdriver, a torque wrench, and a 5/8 inch deep socket for this procedure.

CAUTION. The main board module is particularly sensitive to ESD. Read the

Preventing ESD section on page 6--1 before removing or installing the main board.

Removal. To remove the main board module, refer to Figure 8--3 and follow these steps:

1. Remove the power button and rear case using the procedures on page 6-- 9.

2. Remove the internal assembly from the front case using the procedure on

page 6--12.

3. Disconnect the following wires from the main board by pulling straight up from the connector:

H The power supply cable at J101. Press down on the latch while pulling

up on the cable.

H The display cable at J201.

H The front-panel cable at J202.

4. Use the screwdriver to remove the three screws attaching the main board module to the internal assembly.

5. Use the socket to remove the nuts and washers from the BNC connectors.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--15

Maintenance

6. Pull the board out from the front slots of the internal assembly.

Installation. To install the main board module, refer to Figure 8--3 and follow these steps:

1. Work from the bottom of the internal assembly, and place the front of the main board module into the slots on the internal assembly near the the BNC connectors.

2. Use the deep socket to attach the washers and nuts to each BNC connector so that the main board is securely attached to the chassis.

Support the BNC to prevent it from twisting the main board, and torque the nuts to 40 in-lbs (4.5 N⋅m) using the torque wrench.

3. Install the three screws attaching the main board module to the internal assembly.

4. Reconnect the following wires on the main board:

Display Module

H The power supply cable at J101.

H The display cable at J201.

H The front-panel cable at J202.

5. Use the installation procedure for each module removed to reassemble the oscilloscope.

You will need a torque-limiting Torx T-15 screwdriver, a torque-limiting Torx T-8 screwdriver, and pliers for this procedure.

Removal. To remove the display module, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Remove the power button and rear case using the procedures on page 6-- 9.

2. Remove the internal assembly from the front case using the procedure on

page 6--12.

3. Disconnect the backlight cable from the power supply module.

4. For color displays, follow these steps:

6--16

a. Remove the power supply module using the procedure on page 6--11.

b. Remove the four screws attaching the display module to the chassis. The

screws were exposed when the power supply module was removed.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

5. For monochrome displays, remove the four screws attaching the display module to the internal assembly.

6. Disconnect the display cable using the procedure on page 6--12.

NOTE. Be careful that you do not loosen the mounting posts from the chassis. If the mounting posts should become loosened, it will be necessary to remove the power supply module to access the screws at the other end of the post.

CAUTION. The display shield is attached to the display module. Removing the shield will destroy the attaching gasket.

Installation. To install the display module, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Reconnect the display cable at J201 on the main board by pushing the cable straight down into the connector.

2. Route the display cable through the opening in the chassis. For more information, see the display cable procedure on page 6--12.

3. For color displays, use the Torx T-8 screwdriver and install the four screws to attach the display module to the chassis. Torque the nuts to 3 in-lbs (0.33 N⋅m) using the torque wrench (2.864 +/-- .26 in--lbs).

For 2-channel models, the location and type of screws shown in Figure 8--1 will vary between the color and monochrome displays.

4. For monochrome displays, install the four screws to attach the display module to the internal assembly.

5. Install the power supply module using the procedure on page 6--11.

6. Route the backlight cable through the opening in the internal assembly.

7. Reconnect the backlight cable to the power supply module.

Connect to the black socket for a monochrome display, and to the white socket for a color display.

8. Reconnect the display cable using the installation procedure on page 6--13.

9. Use the installation procedure for each module removed to reassemble the

oscilloscope.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--17

Maintenance

Front-Panel Module

You will need a torque-limiting Torx T-15 screwdriver and a flat-blade screwdriver for this procedure.

Removal. To remove the front-panel module, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Remove the power button and rear case using the procedures on pages 6-- 9.

2. Remove the entire internal assembly from the front case using the procedure

on page 6--12.

3. Disconnect the front-panel cable at J202 on the main board by pulling straight up from the connector.

4. Remove the five screws attaching the front-panel module to the internal assembly.

5. Pull the module away from the internal assembly.

Installation. To install the front-panel module, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Reconnect the front-panel cable at J202 on the main board by pushing the cable straight down into the connector.

Keypad

2. Route the front-panel cable through the opening in the internal assembly. For more information, see the procedure on page 6--14.

3. Install the five screws to attach the front-panel module to the internal assembly.

4. Use the installation procedure for each module removed to reassemble the oscilloscope.

You will need a torque-limiting Torx T-15 screwdriver for this procedure.

Removal. To remove the switch keypad, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Remove the power button and rear case using the procedures on page 6-- 9.

2. Remove the entire internal assembly from the front case using the procedure

on page 6--12.

3. Lift the keypad out of the front case.

6--18

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

CAUTION. Keep the electrical contacts on the back of the keypad clean. Skin oils and dust will inhibit good electrical contact.

Installation. To install the switch keypad, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Place the front case face down on a soft surface.

2. Align the switch keypad into the front case using the guide posts and the

holes in the keypad.

CAUTION. Keep the electrical contacts on the back of the switch pad clean. Skin oils and dust will inhibit good electrical contact.

3. Check that all buttons are properly seated into place before proceeding.

Front Case

4. Place the entire internal assembly into the front case.

5. Use the installation procedure for each module removed to reassemble the

oscilloscope.

You will need a torque-limiting Torx T-15 screwdriver for this procedure.

Removal. To remove the front case, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Remove the power button and rear case using the procedures on page 6-- 9.

2. Remove the entire internal assembly from the front case using the procedure

on page 6--12.

3. Remove the switch keypad using the procedure on page 6--18.

Installation. To install the front case, refer to Figure 8--1 for 2-channel models or Figure 8--2 for 4-channel models, and follow these steps:

1. Place the switch keypad into the front case.

2. Place the entire internal assembly into the front case.

3. Use the installation procedure for each module removed to reassemble the

oscilloscope.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--19

Maintenance

Troubleshooting

This section contains information and procedures to help you isolate a defective module in the oscilloscope.

WARNING. Before doing this or any other procedure in this manual, read the

General Safety Summary and Service Safety Summary found at the beginning of this manual. Also, to prevent possible injury or damage to electrical components, read Preventing ESD on page 6--1.

Adjustment After Repair

Required Tools and

Equipment

If you replace the main board or power supply, you must adjust the oscilloscope after repair. Refer to the chapter Adjustment Procedures.

You may need the the following tools and equipment to troubleshoot the oscilloscope:

Tools and equipment Example

Oscilloscope with 1X/10X and 100X probes Tektronix TDS1000B or TDS2000B series

oscilloscope with standard accessory 1X/10X probe (P2220) and optional 100X probe (P5100 or P5200)

DMM 3.5 or greater digit DMM

USB flash drive Tektronix part number 119-7276-00, 128 MB

USB type A to type B cable Tektronix part numbers:

174-4401-00, .91 meters (3 feet) 174-5194-00, 1.83 meters (6 feet)

PC with USB host post and with TekVISA (OpenChoice PC Communications) installed

PC with USB communication port

Troubleshooting Tree

6--20

To isolate a problem to a specific troubleshooting procedure, use the troubleshooting tree in Figures 6--4, 6--5, 6--6 and 6--7. Detailed procedures follow the tree.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

Put scope or

frequency counter

on probe comp

1 kHz?

Yes

Verify LCD

connector and

cable values

Replace main

board

Run probe check

on each channel

Turn on power

Does screen

lighten?

Yes

See

boot up

screen?

Yes

Errors?

Front panel

problems?

Yes

From Figure 6-6

To Figure 6-6

To Figure 6-5

Yes

Replace display or display cable

Probe

check Ok?

Yes

Connect external trigger to probe comp

Set trigger

source to EXT

Press set 50%

Good

voltages?

Replace main

board

Figure 6--4: Oscilloscope troubleshooting tree (1 of 4)

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Replace main

board

Trigger

indicator ON?

Yes

Replace main

board

To Figure 6-7

6--21

Maintenance

From Figure 6-4

Able to run front panel

tests?

Yes

Run front panel

tests in service

<5key

problem

Yes

Replace front

panel board

Check cabling to

main board.

Replace cable;

front panel or main

board

Check cabling to

main board;

Replace cable or

main board

Verify power

supply voltages

Power

supplies OK?

Yes

Replace main

board

Replace power

supply

Disconnect

power supply

Verify power

supply Voltages

Power

supplies OK?

Yes

Replace main

board

Figure 6--5: Oscilloscope troubleshooting tree (2 of 4)

6--22

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

To Figure 6-4

From Figure 6-4

Power cord

attached?

Yes

Open case

Fuse OK?

Yes

Backlight cable

attached?

Yes

Using a high

voltage 100X

probe test voltages

on backlight

connectors

Attach power

cord

Reinstall case

Replace power

supply

Attach backlight

cable

~50 kHz

>700 V

Detach display

~50 kHz

>700 V

Replace power

supply

pk--pk

Figure 6--6: Oscilloscope troubleshooting tree (3 of 4)

Yes

Replace display

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--23

Maintenance

Install a compatible

USB flash drive in

the front--panel port

Does the

flash drive

blink?*

Yes

Examine the

contents of the

flash drive through

the file controls

Does

the data

match what is

visible on the

PC?

Yes

Check that the

TekVISA software

(OpenChoice PC

Communications) is

installed on the PC

Connect the

oscilloscope to

the PC

Replace the

Main board

Does the data match what is

visible on the

oscilloscope?

From Figure 6-4

Yes

Transfer data from

the oscilloscope to

the PC

* The oscilloscope displays a clock symbol when the flash drive is active, and a hint line when a save or recall operation is complete.

Good oscilloscope

Figure 6--7: Oscilloscope troubleshooting tree (4 of 4)

6--24

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Maintenance

PROBE COMP Output

Troubleshooting the

Power Supply

When the oscilloscope is on and operating properly, the PROBE COMP output should generate a square wave, approximately 5 V in amplitude, at a 1 kHz frequency. Use the oscilloscope and set the Attenuation switch to 10X on the P2220 probe to probe this output.

As shown in the table below, there are two cases of defects. Either the 1 kHz signal is on and the power supply and main board are both active and functionally capable of doing acquisition, or one of those two modules is not performing correctly. While a large number of different possible frequencies exist, all involve detected failures on the main board due to main board failure or power supply failure.

Signal at PROBE COMP Possible problem

1 kHz signal, no display Refer to Troubleshooting the Display (page 6--26)

Non-1 kHz signal Refer to Troubleshooting the Main Board (page 6--32)

No signal Refer to Troubleshooting the Power Supply (page 6--25)

To troubleshoot the power supply, follow these steps:

1. Remove the rear case using the procedure Rear Case on page 6--9.

2. Use the test oscilloscope to measure the voltages from the power supply

module at J101 on the main board module. The table below lists the voltages you should expect to see.

Maximum current

Supply Voltage range*

35 V 30 VDCto 40 VDCfloating.

Pin 2 connected to +3.3 V on the main board.

+6 V 5.5 V to 6.5 V 0.7 A 4 3, 5, 8,10+5 V

+3.3 V 3.0 V to 3.6 V. Requires

minimum load to maintain regulation.

-- 4 V -- 5 . 0 V t o -- 3 . 5 V 0.8 A 9 3, 5, 8,10-- 2 . 5 V

Line trigger --2 V to 6 V open circuit.

±1 diode drop when attached to the main board.

draw

15 mA 1 2 +28 V LCD

1.5 A 6, 7 3, 5, 8,103.3 V, +2.5 V

1mA 11 3, 5, 8,10Line trigger

J101 power pins

J101 return pins

Derived supplies

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--25

Maintenance

Maximum current

Supply

Backlight (monochrome or color)

With 3 W minimum load; still functions with no load.

Voltage range*

>500 V

, ∼50 kHz NA NA NA

pk-pk

draw

J101 power pins

J101 return pins

Derived supplies

3. If all of the voltages are present, the main board is probably defective. Replace it.

4. If all or some of the voltages are missing, turn off the oscilloscope and disconnect the cable at connector J101 on the main board module.

5. Turn on the oscilloscope and check the voltages at the loose end of the cable disconnected from J101, checking for the same voltages as in step 2.

6. If all of the voltages are missing, check the line fuse on the power supply module. If the fuse is defective, replace the power supply module.

7. If the fuse is okay, and all or some of the voltages are missing, the power supply module is probably defective. Replace it.

Troubleshooting the

Display

To troubleshoot a nonfunctional display, follow these steps:

1. Remove the rear case using the procedure Rear Case on page 6--9.

2. Turn on the oscilloscope and ensure that the display lights up. If it does not,

either the display or power supply is defective. If this procedure is not conclusive, continue with Troubleshooting the Power Supply on page 6--25.

NOTE. Without a functional display module, the simplest way to verify that the oscilloscope is on and functioning is to check for a signal at the PROBE COMP output. The PROBE COMP output generates approximately a 5 V, 1 kHz square wave.

3. Use the test oscilloscope and set the Attenuation s witch to 10X on the P2200 probe to probe the display cable connector at J201 on the main board. The following table describes the signals you should expect to see.

See the exploded diagrams in Replaceable Parts for the location and orientation of the connector on the main board.

6--26

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Signal at J201 Description, Monochrome Description, Color

Pin 1 (marked with

A )

No fixed pattern. Depends upon display data.

Maintenance

Pin 2 No fixed pattern. Depends upon

display data.

Pin 3 No fixed pattern. Depends upon

display data.

Pin 4 No fixed pattern. Depends upon

display data.

No fixed pattern. Depends upon display data.

Pin 5 Not connected No fixed pattern. Depends upon

display data.

Pin 6 Not connected No fixed pattern. Depends upon

display data.

Pin 7 Not connected No fixed pattern. Depends upon

display data.

Pin 8 Not connected No fixed pattern. Depends upon

display data.

Pin 9 24 V

26.5 V

Pin 10 Ground Ground

Pin 11 +5 V

+5 V

Pin 12 HI when display active HI when display active

Pin 13 Data rate clock.

1.36 MHz Square wave

Data rate clock.

1.36 MHz Square wave

Pin 14 Line rate clock

17 kHz, 500 ns high pulse from low baseline

Pin 15 Frame rate clock

70 Hz, 750 ns high pulse from low baseline

Pin 16 Low

Line rate clock

11.4 kHz, 500 ns high pulse from low baseline

Frame rate clock 43 Hz, 350 ns high pulse from low baseline

High (> 2.4 V)

Pin 17 Ground Ground

Pin 18 Ground Ground

Value varies with temperature, contrast setting, and display type.

Frequency may vary slightly with software version.

With monochrome display cable attached. If no cable is attached, default condition is High (color).

TDS1000B and TDS2000B Series Oscilloscope Service Manual

6--27

Maintenance

4. If all the signals are present, the display module is probably defective. Replace it.

5. If all or some of the signals are missing, turn off the oscilloscope and disconnect the display cable at J201 on the main board. Carefully pull the cable straight up from the connector to avoid damage.

6. Turn on the oscilloscope.

7. Probe the pins of J201, checking for the same signals as in step 3.

8. If any of the signals are missing, the main board module is probably

defective. Replace it.

Troubleshooting the

Backlight

To troubleshoot a nonfunctional backlight, follow these steps:

1. Remove the rear case using the procedure Rear Case on page 6--9.

2. Turn on the oscilloscope.

WARNING. To avoid electrical shock, do not touch the backlight connectors on the power supply module. See Figure 6--8 for the location of the connectors. Typically, the monochrome connector is black and the color connector is white.

3. Set the test oscilloscope (with a 100X probe) to measure a 1270 V (450 V

) signal at approximately 50 kHz.

RMS

pk-pk

4. Attach the probe ground lead to the ground lug on the AC line connector and the probe tip to one of the leads on the backlight connector as shown in Figure 6--8. Record the voltage of the signal.

5. Attach the probe tip to the other lead on the backlight connector as shown in Figure 6--8. Record the voltage of the signal.

6--28

TDS1000B and TDS2000B Series Oscilloscope Service Manual

AC ground lug

Maintenance

Backlight voltage test points

Figure 6--8: Measuring the backlight voltage

6. Add the results of both readings. If a signal greater than 1400 V present, the backlight is probably defective. Replace the display.

If the signal is not present, proceed with step 7.

7. If the signal is missing, detach the display using the procedure on page 6--16 and probe the backlight connector leads again.

8. Add the results of both readings. If a signal greater than 1400 V present, the display is probably defective. Replace it.

If the signal is not present, the power supply module is probably defective. Replace it.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

pk-pk

6--29

Maintenance

Troubleshooting the Front

Panel

To troubleshoot an improperly functioning front panel, follow these steps:

1. To execute the internal diagnostic tests, remove all input signals from the oscilloscope and enable the Service menu as described on page 5--2.

2. Push the UTILITY button and push the Service option button. The following options appear:

Menu Comments

Factory Cal Steps through the calibration routine steps.

Tota l I ni t Writes factory default settings to all saved setups, writes factory default data to

all reference waveforms, turns off Service Mode, and performs the same actions as the front-panel DEFAULT SETUP button.

Service Diag. Displays the service diagnostics menus.

Service Mode Off

Disables the Service menu.

3. Select Service Diag. The following options appear:

Menu Comments

Mfg. Tests Displays a front-panel simulation used to check that all front panel controls are

operational.

Loop Diag. Opens a menu that enables you to re-run a subset of the power-on self tests.

Peek/Poke For engineering use only

Clear Error Log Removes all Error Log entries from memory and sets the power cycle count to

zero.

6--30

4. Select Mfg. Tests to start the front-panel controls test. The following options appear:

Menu Comments

Test F P Displays a front-panel simulation used to check the operation of all front panel

controls.

All buttons must be pushed and all knobs must be turned in both directions before you can exit this test.

Test Screen Checks the display screen pixels with different patterns from each push of the

button.

Contrast Allows you to check the display contrast operation across 100% of the

hardware range.

TDS1000B and TDS2000B Series Oscilloscope Service Manual

Tektronix TDS1001B, TDS1002B, TDS1012B, TDS2002B, TDS2004B Service

Specifications and Main Features

Frequently Asked Questions

User Manual

List of Figures

List of Tables

General Safety Summary

Terms in this Manual

Service Safety Summary

Preface

Manual Conventions

Related Documentation

Specifications

Operating Information

Theory of Operation

Main Board

Power Supply

Display Module

Front Panel

Performance Verification

Required Equipment

Test Record

Performance Verification Procedures

Adjustment Procedures

Required Equipment

Adjustment Procedure

Maintenance

Preventing ESD

Inspection and Cleaning

Removal and Installation Procedures

Troubleshooting