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Service Manual

TDS 340A, TDS 360 & TDS 380 Digital Real-Time Oscilloscopes 070-9435-03

This document applies to firmware version 1.05 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.

Copyright © Tektronix, Inc. All rights reserved. Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes that in all previously published material. Specifications and price change privileges reserved. Printed in the U.S.A. Tektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070­1000 TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

WARRANTY
Tektronix warrants that the products that it manufactures and sells will be free from defects in materials and workmanship for a period of three (3) years from the date of purchase from an authorized Tektronix distributor. If any such product proves defective during this warranty period, Tektronix, at its option, either will repair the defective product without charge for parts and labor, or will provide a replacement in exchange for the defective product. Batteries are excluded from this warranty. In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for packaging and shipping the defective product to the service center designated by Tektronix, shipping charges prepaid, and with a copy of customer proof of purchase. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which the Tektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations.

Table of Contents

General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Service Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

vii xi xiii

Specifications
Warranted Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Typical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nominal Traits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­1 1­5 1­7

Operating Information
Display and Power Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vertical Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Horizontal Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Trigger Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Miscellaneous Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Display Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear-Panel Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using the Menu System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­1 2­2 2­2 2­3 2­3 2­4 2­5 2­6 2­7

Theory of Operation
Logic Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Module Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­1 3­1

Performance Verification
Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Test Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4­1
4­3 4­4

Self Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Functional Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Performance Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Signal Acquisition System Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Time Base System Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Trigger System Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sine Wave Generator Leveling Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4­5 4­7 4­11
4­11 4­11 4­16 4­18 4­20

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Contents

Adjustment Procedures
Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The System Calibration Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Attenuator Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Monitor Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5­1 5­2 5­4 5­6

Maintenance
Preventing ESD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Cleaning Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6­1 6­2
6­2

Removal and Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preparation -- Please Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Line Fuse and Line Cord . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front Panel Knobs and Shafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear Cover, Cabinet, and Cabinet Handle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Trim Ring, Menu Elastomer, Menu Buttons, and Front EMI Gaskets . . . . . . . . Front Panel Assembly and Menu Flex Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . Main Board Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Monitor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Supply Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Option 14 Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fan and Fan Mount . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6­5
6­5 6­8 6­10 6­11 6­13 6­14 6­16 6­18 6­21 6­23 6­25 6­27

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Onboard Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Enabling Calibration Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6­29
6­29 6­31 6­32

Repackaging Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6­43

Options
Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accessory Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accessory Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7­1 7­3 7­3 7­4 7­4

Electrical Parts List
Electrical Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8­1

Diagrams
Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9­1

Mechanical Parts List
Parts Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using the Replaceable Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10­1 10­2

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Contents

List of Figures
Figure 1­1: TDS 340A, TDS 360, & TDS 380 dimensions . . . . . . . . . . Figure 2­1: A pop-up menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2­2: Using menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 3­1: TDS 340A, TDS360, & TDS380 block diagram . . . . . . . . Figure 3­2: TDS 340A, TDS360, & TDS380 block diagram with Option 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4­1: Menu locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4­2: Verifying adjustments and signal path compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4­3: Hookup for functional test . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4­4: Hookup for file system functional test . . . . . . . . . . . . . . . Figure 4­5: Hookup for DC voltage measurement accuracy check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4­6: Hookup for analog bandwidth check . . . . . . . . . . . . . . . . Figure 4­7: Measuring analog bandwidth . . . . . . . . . . . . . . . . . . . . . . Figure 4­8: Hookup for sample rate check . . . . . . . . . . . . . . . . . . . . . . Figure 4­9: Hookup for trigger sensitivity check . . . . . . . . . . . . . . . . . Figure 4­10: Measuring trigger sensitivity . . . . . . . . . . . . . . . . . . . . . . Figure 4­11: Hookup for sine wave generator leveling . . . . . . . . . . . . Figure 5­1: The system calibration menu . . . . . . . . . . . . . . . . . . . . . . . Figure 5­2: Timing compensation waveform . . . . . . . . . . . . . . . . . . . . Figure 5­3: Attenuator adjustment setup and locations . . . . . . . . . . . Figure 5­4: Monitor adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­1: Oscilloscope orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­2: Line cord removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­3: Line fuse removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­4: Knob and shaft removal . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­5: Rear cover, cabinet, and cabinet handle and feet removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­6: Removing the disk drive . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­7: Trim ring, menu elastomer, and menu buttons removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­11 2­8 2­9 3­2 3­3 4­2 4­6 4­7 4­9 4­12 4­14 4­15 4­16 4­18 4­19 4­21 5­2 5­4 5­5 5­7 6­6 6­8 6­9 6­10 6­12 6­13 6­14

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Contents

Figure 6­8: EMI gasket removal and installation . . . . . . . . . . . . . . . . Figure 6­9: Front panel assembly and menu flex circuit removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­10: Removing the floppy interface board . . . . . . . . . . . . . . . Figure 6­11: Removing the main board . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­12: Monitor assembly removal . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­13: Low voltage power supply removal . . . . . . . . . . . . . . . . . Figure 6­14: Option 14 assembly removal . . . . . . . . . . . . . . . . . . . . . . Figure 6­15: Fan and fan mount removal . . . . . . . . . . . . . . . . . . . . . . . Figure 6­16: The diagnostics menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­17: The error log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­18: Main board cal jumper . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­19: Primary troubleshooting procedure . . . . . . . . . . . . . . . . Figure 6­20: Module isolation troubleshooting procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­21: Front panel/processor troubleshooting procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­22: Monitor troubleshooting procedure . . . . . . . . . . . . . . . . Figure 6­23: J901 pin 7 signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­24: J901 pin 2 signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­25: J901 pin 5 signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­26: Power supply troubleshooting procedure . . . . . . . . . . . . Figure 6­27: Power supply connector locations . . . . . . . . . . . . . . . . . . Figure 6­28: Power supply overload troubleshooting procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­29: Option 14 I/O interfaces troubleshooting procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 10­1: Cabinet and front panel assembly . . . . . . . . . . . . . . . . . . Figure 10­2: CRT, power supply, and circuit boards . . . . . . . . . . . . . Figure 10­3: Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6­16 6­17 6­19 6­20 6­22 6­24 6­26 6­27 6­29 6­31 6­32 6­33 6­34 6­35 6­36 6­37 6­37 6­38 6­39 6­40 6­41 6­42 10­6 10­8 10­10

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Contents

List of Tables
Table 1­1: Warranted characteristics -- signal acquisition system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­2: Warranted characteristics -- time base system . . . . . . . . Table 1­3: Warranted characteristics -- triggering system . . . . . . . . Table 1­4: Power Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­5: Warranted characteristics -- environmental . . . . . . . . . . Table 1­6: Typical characteristics -- signal acquisition system . . . . . Table 1­7: Typical characteristics -- triggering system . . . . . . . . . . . Table 1­8: Typical characteristics -- probe compensator output . . . Table 1­9: Typical characteristics -- data handling . . . . . . . . . . . . . . Table 1­10: Nominal traits -- signal acquisition system . . . . . . . . . . Table 1­11: Nominal traits -- time base system . . . . . . . . . . . . . . . . . Table 1­12: Nominal traits -- triggering system . . . . . . . . . . . . . . . . . Table 1­13: Nominal traits -- display system . . . . . . . . . . . . . . . . . . . Table 1­14: Nominal traits -- Option 14 I/O interface option (TD3F14A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­15: Nominal traits -- power distribution system . . . . . . . . . Table 1­16: Nominal traits -- mechanical characteristics . . . . . . . . . Table 1­17: Certifications and compliances . . . . . . . . . . . . . . . . . . . . . Table 4­1: Test equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 4­2: DC accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 5­1: Adjustment equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 6­1: External inspection check list . . . . . . . . . . . . . . . . . . . . . . . Table 6­2: Internal inspection check list . . . . . . . . . . . . . . . . . . . . . . . Table 6­3: Tools required for module removal . . . . . . . . . . . . . . . . . . Table 6­4: Power supply secondary voltages . . . . . . . . . . . . . . . . . . . . 1­1 1­2 1­3 1­3 1­4 1­5 1­6 1­6 1­7 1­7 1­8 1­8 1­9 1­9 1­9 1­10 1­12 4­3 4­11 5­1 6­3 6­4 6­6 6­40

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Table 7­1: VGA output connector pins . . . . . . . . . . . . . . . . . . . . . . . . Table 7­2: International power cords . . . . . . . . . . . . . . . . . . . . . . . . . . Table 7­3: Language options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 7­4: Standard accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 7­5: Optional accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 7­6: Accessory cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 10­1: Certifications and compliances . . . . . . . . . . . . . . . . . . . . .

7­1 7­2 7­2 7­3 7­3 7­4 10­1

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TDS 340A, TDS 360 & TDS 380 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 the product only as specified. Only qualified personnel should perform service procedures. While using this product, you may need to access other parts of the system. Read the General Safety Summary in other system manuals for warnings and cautions related to operating the system.

Injury Precautions

Use Proper Power Cord. To avoid fire hazard, use only the power cord specified for this product. Avoid Electric Overload. To avoid electric shock or fire hazard, do not apply a voltage to a terminal that is outside the range specified for that terminal. Avoid Overvoltage. To avoid electric shock or fire hazard, do not apply potential to any terminal, including the common terminal, that varies from ground by more than the maximum rating for that terminal. Avoid Electric Shock. To avoid injury or loss of life, do not connect or disconnect probes or test leads while they are connected to a voltage source. 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. Do Not Operate Without Covers. To avoid electric shock or fire hazard, do not operate this product with covers or panels removed. Use Proper Fuse. To avoid fire hazard, use only the fuse type and rating specified for this product. Do Not Operate in Wet/Damp Conditions. To avoid electric shock, do not operate this product in wet or damp conditions. Do Not Operate in an Explosive Atmosphere. To avoid injury or fire hazard, do not operate this product in an explosive atmosphere. Avoid Exposed Circuitry. To avoid injury, remove jewelry such as rings, watches, and other metallic objects. Do not touch exposed connections and components when power is present. Keep Probe Surface Clean and Dry. To avoid electric shock and erroneous readings, keep probe surface clean and dry.

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General Safety Summary

Wear Eye Protection. To avoid eye injury, wear eye protection if there is a possibility of exposure to high-intensity rays.

Product Damage Precautions

Use Proper Power Source. Do not operate this product from a power source that applies more than the voltage specified. Provide Proper Ventilation. To prevent product overheating, provide proper ventilation. Do Not Operate With Suspected Failures. If you suspect there is damage to this product, have it inspected by qualified service personnel. Do Not Immerse in Liquids. Clean the probe using only a damp cloth. Refer to cleaning instructions.

Symbols and Terms

Terms in this Manual. 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.

Terms on the Product. These terms may appear on the product: DANGER indicates an injury hazard immediately accessible as you read the marking. WARNING indicates an injury hazard not immediately accessible as you read the marking. CAUTION indicates a hazard to property including the product.

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TDS 340A, TDS 360 & TDS 380 Service Manual

General Safety Summary

Symbols on the Product. The following symbols may appear on the product:

DANGER High Voltage

Protective Ground (Earth) Terminal

ATTENTION Refer to Manual

Double Insulated

Certifications and Compliances

Refer to the specifications section for a listing of certifications and compliances that apply to this product.

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General Safety Summary

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TDS 340A, TDS 360 & TDS 380 Service Manual

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, disconnect the main power by means of the power cord or, if provided, the power switch. Use Caution When Servicing the CRT. To avoid electric shock or injury, use extreme caution when handling the CRT. Only qualified personnel familiar with CRT servicing procedures and precautions should remove or install the CRT. CRTs retain hazardous voltages for long periods of time after power is turned off. Before attempting any servicing, discharge the CRT by shorting the anode to chassis ground. When discharging the CRT, connect the discharge path to ground and then the anode. Rough handling may cause the CRT to implode. Do not nick or scratch the glass or subject it to undue pressure when removing or installing it. When handling the CRT, wear safety goggles and heavy gloves for protection. 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. X-Radiation. To avoid x-radiation exposure, do not modify or otherwise alter the high-voltage circuitry or the CRT enclosure. X-ray emissions generated within this product have been sufficiently shielded.

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Service Safety Summary

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Preface
This service manual provides service information for the TDS 340A, TDS 360, and TDS 380 Digitizing Oscilloscopes.

Manual Structure
This manual is divided into Chapters such as Specifications and Theory of Operation. Further, it is divided into subsections such as Product Description and Removal and Installation Procedures. Sections containing procedures also contain introductions to those procedures. Be sure to read these introductions because they provide information needed to do the service correctly and efficiently. The following is a brief description of each manual chapter. H H H H Specifications contains a product description of the digitizing oscilloscope and tables of the characteristics and descriptions that apply to it. Operating Information includes general information and operating instructions at the level needed to safely power on and service this oscilloscope. Theory of Operation contains circuit descriptions that support general service and fault isolation down to the module level. Performance Verification contains a collection of procedures for confirming that this digitizing oscilloscope functions properly and meets warranted limits. Adjustment Procedures contains a collection of procedures for adjusting this digitizing oscilloscope to meet warranted limits. Maintenance contains information and procedures for doing preventive and corrective maintenance of the digitizing oscilloscope. Instructions for cleaning, for module removal and installation, and for fault isolation to a module are found here. Options contains information on the factory-installed options that may be present in your oscilloscope. Electrical Parts List contains a statement referring you to the Mechanical Parts List, where both electrical and mechanical modules are listed.

H H

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Diagrams contains a statement referring you to the Theory of Operation Chapter, where module-level block diagrams are listed. Mechanical Parts List includes a table of all replaceable modules, their descriptions, and their Tektronix part numbers.

Manual Conventions
This manual uses certain conventions which you should become familiar with before doing service.

Modules

Throughout this manual, any replaceable component, assembly, or part of this digitizing oscilloscope is referred to generically as a module. In general, a module is an assembly, like a circuit board, rather than a component, like a resistor or an integrated circuit. Sometimes a single component is a module; for example, the chassis of the oscilloscope is a module. Symbols and terms related to safety appear in the General Safety Summary and Service Safety Summary found at the beginning of this manual. Besides the symbols related to safety, this manual uses the following symbols: STOP. This "stop sign" labels information which you must read in order to correctly do service and to avoid incorrectly using or applying service procedures.

Safety

Symbols

Related Manuals
These other manuals are available for the TDS 340A, TDS 360, and TDS 380 Digitizing Oscilloscopes. H H H The Reference Manual gives you a quick overview of how to operate your oscilloscope. The User Manual provides instructions on how to operate your oscilloscope. The Programmer Manual provides complete information on programming and remote control of the oscilloscope through the GPIB or RS-232 interface (optional accessory).

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Specifications
This appendix contains complete specifications for the TDS 340A, TDS 360, and TDS 380. The specifications are divided into three subsections, one for each of three classes of traits: Warranted Characteristics, Typical Characteristics, and Nominal Traits.

Warranted Characteristics
Warranted characteristics are described in terms of quantifiable performance limits that are warranted. This subsection lists only warranted characteristics. NOTE. In these tables, those warranted characteristics that are checked in the Performance Tests, starting on page 4­11, appear in boldface type under the column Name.

Performance Conditions

The electrical characteristics found in these tables of warranted characteristics apply when the oscilloscope has been adjusted at an ambient temperature between +20_ C and +30_ C, has had a warm-up period of at least 20 minutes, and is operating at an ambient temperature between ­10_ C and +55_ C (unless otherwise noted).

Table 1­1: Warranted characteristics -- signal acquisition system
Name Accuracy, DC Voltage Measurement, Average Ac ui i i M de Acquisition Mode Description Measurement type Average of 16 waveforms Delta volts between any two averages of 16 waveforms acquired under the same setup and ambient conditions Accuracy, DC Gain, Sample or Average Acquisition Modes Pulse Response, Peak Detect and E vel pe M de Envelope Mode ±2% Sec/Div setting 5 s/div ­ 25 ms/div TDS 340A: 10 ms/div ­ 5 ns/div TDS 360: 10 ms/div ­ 2.5 ns/div TDS 380: 10 ms/div ­ 1 ns/div Minimum pulse width 10 ns The greater of 10 ns or .02 × sec/div setting DC accuracy ±(2.0% × |(reading ­ Net Offset1)| + Offset Accuracy + 0.1 div) ±(2.0% × |reading| + 0.15 div + 0.3 mV)

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Table 1­1: Warranted characteristics -- signal acquisition system (Cont.)
Name Accuracy, Offset Description Volts/Div setting 2 mV/div ­ 99.5 mV/div 100 mV/div ­ 995 mV/div 1 V/div ­ 10 V/div Analog Bandwidth, DC Coupled Offset accuracy ±(0.4% × |Net Offset1| + 3 mV + 0.1 div × V/div setting) ±(0.4% × |Net Offset1| + 30 mV + 0.1 div × V/div setting) ±(0.4% × |Net Offset1| + 300 mV + 0.1 div × V/div setting)

TDS 340A: DC ­ 100 MHz TDS 360: DC ­ 200 MHz; DC ­ 180 MHz for 2 mV/div TDS 380: DC ­ 400 MHz; DC ­ 250 MHz for 2 mV/div 100:1 at 50 MHz with equal Volts/Div settings on each channel TDS 340A: 1 MW ±1% in parallel with 20 pF ±2.0 pF TDS 360: 1 MW ±1% in parallel with 20 pF ±2.0 pF TDS 380: 1 MW ±1% in parallel with 12 pF ±2.0 pF ±300 V (DC or AC) CAT II; derate at 20 dB/decade above 100 kHz to 13 V peak AC at 3 MHz and above 10 Hz

Cross Talk (Channel Isolation) Input Impedance, DC-Coupled

Input Voltage, Maximum Lower Frequency Limit, AC Coupled2
1

Net Offset = Offset ­ (Position × Volts/Div). Net offset is the voltage level at the center of the A-D converter dynamic range. Offset Accuracy is the accuracy of this voltage level. The AC Coupled Lower Frequency Limits are reduced by a factor of 10 when 10X, passive probes are used.

2

Table 1­2: Warranted characteristics -- time base system
Name Accuracy, Long Term Sample Rate and Delay Time Accuracy, Delta Time Measurements1, 2 Description ±100 ppm over any 1 ms interval For single-shot acquisitions using sample acquisition mode and a bandwidth limit setting of FULL: ±(1 WI + 100 ppm × |Reading| + 0.6 ns) For repetitive acquisitions using average acquisition mode with 16 averages and a bandwidth limit setting of FULL: ±(1 WI + 100 ppm × |Reading| + 0.4 ns)
1

For input signals 5 divisions in amplitude and a slew rate of 2.0 divisions/ns at the delta time measurement points. Signal must be acquired at a volts/division setting 5 mV/division. The WI (waveform interval) is the time between the samples in the waveform record. Also, see the footnotes for Sample Rate Range and Equivalent Time or Interpolated Waveform Rates in Table 1­11 on page 1­8.

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Table 1­3: Warranted characteristics -- triggering system
Name Accuracy, Trigger Level, DC Coupled Description Trigger source CH1 or CH2 External External/10 Sensitivity, Edge-Type Trigger, DC Coupled upled Trigger source CH1 or CH2 Sensitivity ±(3% of |Setting ­ Net Offset1| + 0.2 div × volts/div setting + Offset Accuracy) ±(6% of |Setting| + 20 mV) ±(6% of |Setting| + 200 mV) Sensitivity TDS 340A: 0.35 division from DC to 20 MHz, increasing to 1 div at 100 MHz TDS 360: 0.35 division from DC to 50 MHz, increasing to 1 div at 200 MHz TDS 380: 0.35 division from DC to 50 MHz, increasing to 1 div at 400 MHz External TDS 340A: 50 mV from DC to 20 MHz, increasing to 150 mV at 100 MHz TDS 360: 50 mV from DC to 50 MHz, increasing to 150 mV at 200 MHz TDS 380: 50 mV from DC to 50 MHz, increasing to 500 mV at 400 MHz External/10 TDS 340A: 500 mV from DC to 20 MHz, increasing to 1.5 V at 100 MHz TDS 360: 500 mV from DC to 50 MHz, increasing to 1.5 V at 200 MHz TDS 380: 500 mV from DC to 50 MHz, increasing to 5.0 V at 400 MHz Input Impedance, External Trigger Maximum Input Voltage, External Trigger
1

1 MW ±2% in parallel with 20 pF ±2 pF ±300 V (DC or AC) CAT II; derate at 20 dB/decade above 100 kHz to 13 V peak AC at 3 MHz and above

Net Offset = Offset ­ (Position × Volts/Div). Net Offset is the voltage level at the center of the A-D converter dynamic range. Offset Accuracy is the accuracy of this voltage level.

Table 1­4: Power Requirements
Name Source Voltage and Frequency Power Consumption Description 90 to 132 VACRMS, continuous range, for 47 Hz through 440 Hz 132 to 250 VACRMS, continuous range, for 47 Hz through 63 Hz 65 Watts (120 VA)

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Table 1­5: Warranted characteristics -- environmental
Name Atmospherics (TDS 340A, TDS 360 or TDS 380) Description Temperature without diskette in floppy disk drive: +4_ C to +50_ C, operating; ­22_ C to +60_ C, non-operating Temperature with diskette in floppy disk drive: +10_ C to +50_ C, operating or non-operating Relative humidity without diskette in floppy disk drive: to 80% at or below +29_ C, or to 20% from +30_ C to +50_ C, operating; to 90% at or below +40_ C, or to 5% from +41_ C to +50_ C, non-operating; Relative humidity with diskette in floppy disk drive: to 80% at or below +29_ C, or to 20% from +30_ C to +50_ C, operating or non-operating Altitude: To 15,000 ft (4570 m), operating; to 40,000 ft (12190 m), non-operating Dynamics Random vibration without diskette in floppy disk drive: 0.31 g RMS, from 5 to 500 Hz, 10 minutes each axis, operating; 2.46 g RMS, from 5 to 500 Hz, 10 minutes each axis, non-operating

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Typical Characteristics
Typical characteristics are described in terms of typical or average performance. Typical characteristics are not warranted. Table 1­6: Typical characteristics -- signal acquisition system
Name Accuracy, DC Gain, Envelope Acquisition Mode Description ±3% for sec/div settings from 5 Sec/Div to 25 msec/div; ±2% for sec/div settings from 10 ms/div to 5 ns/div (TDS 340A); ±2% for sec/div settings from 10 ms/div to 2.5 ns/div (TDS 360); ±2% for sec/div settings from 10 ms/div to 1 ns/div (TDS 380) Measurement type Any Sample Delta Volts between any two samples2 acquired under the same setup and ambient conditions Frequency Limit, Upper, 20 MHz Bandwidth Limited Step Response Settling Error 20 MHz Volts/Div setting e i g 2 mV/div ­ 99.5 mV/div 100 mV/div ­ 995 mV/div 1 V/div ­ 10 V/div Common Mode Rejection Ratio (CMRR)
1

Accuracy, DC Voltage Measurement, Sample Ac isitio Mode m le Acquisition o e

DC accuracy ±(2.0% × (|reading ­ Net Offset1|) + Offset Accuracy + 0.13 div + 0.6 mV) ±(2.0% × |reading| + 0.26 div + 1.2 mV)

Step amplitude a pli ude 2 V 20 V 200 V

Settling error (%)3 100 ns 1.0 1.5 2.5 20 ms 0.1 0.2 0.2

100:1 at 60 Hz, reducing to 20:1 at 50 MHz, with equal Volts/Div and Coupling settings on each channel.

Net Offset = Offset ­ (Position × Volts/Div). Net Offset is the voltage level at the center of the A-D converter dynamic range. Offset Accuracy is the accuracy of this voltage level. The samples must be acquired under the same setup and ambient conditions. The values given are the maximum absolute difference between the value at the end of a specified time interval after the mid-level crossing of the step, and the value one second after the mid-level crossing of the step, expressed as a percentage of the step amplitude.

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Table 1­7: Typical characteristics -- triggering system
Name Error, Trigger Position, Edge Triggering Description Acquire mode Sample, Average Peak Detect, Envelope Sensitivity, Video-Type Trigger Source CH1 or CH2 External External/10 Lowest Frequency for Successful Operation 50 Hz of "Set Level to 50%" Function Sensitivity, Edge Type Trigger, Not DC Coupled3 o le Trigger coupling AC Noise Reject High Frequency Reject Low Frequency Reject Typical signal level for stable triggering Same as DC-coupled limits4 for frequencies above 60 Hz. Attenuates signals below 60 Hz. Three and one half times the DC-coupled limits.4 One and one half times times the DC-coupled limits4 from DC to 30 kHz. Attenuates signals above 30 kHz. One and one half times the DC-coupled limits4 for frequencies above 80 kHz. Attenuates signals below 80 kHz. Trigger-position error1,2 ±(1 WI + 2 ns) ±(2 WI + 2 ns) Typical sensitivity 0.6 division of video sync signal 75 mV of video sync signal 750 mV of video sync signal

1

The trigger position errors are typically less than the values given here. These values are for triggering signals having a slew rate at the trigger point of ±0.5 division/ns. The waveform interval (WI) is the time between the samples in the waveform record. Also, see the footnote for the characteristics Sample Rate Range and Equivalent Time or Interpolated Waveform Rates in Table 1­11 on page 1­8. The minimum sensitivity for obtaining a stable trigger. A stable trigger results in a uniform, regular display triggered on the selected slope. The trigger point must not switch between opposite slopes on the waveform, and the display must not "roll" across the screen on successive acquisitions. The TRIG'D LED stays constantly lighted when the SEC/DIV setting is 2 ms or faster but may flash when the SEC/DIV setting is 10 ms or slower. See the characteristic Sensitivity, Edge-Type Trigger, DC Coupled in Table 1­3, which begins on page 1­3.

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4

Table 1­8: Typical characteristics -- probe compensator output
Name Output Voltage and Frequency, Probe om e s tor Pro e Compensator Description Characteristic Voltage Frequency 5.0 V (low-high) into a 1 MW load 1 kHz

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Table 1­9: Typical characteristics -- data handling
Name Time, Data-Retention, Nonvolatile Memory1,2
1

Description 5 Years

The time that reference waveforms, stored setups, and calibration constants are retained when there is no power to the oscilloscope. Data is maintained by a lithium poly-carbon monofluoride battery.

2

Nominal Traits
Nominal traits are described using simple statements of fact such as "Two, identical" for the trait "Input Channels, Number of," rather than in terms of limits that are performance requirements. Table 1­10: Nominal traits -- signal acquisition system
Name Bandwidth Selections Digitizers, Number of Digitized Bits, Number of Input Channels, Number of Input Coupling Ranges, Offset, All Channels Description 20 MHz and FULL Two, identical, digitized simultaneously 8 bits1 Two, identical, called CH 1 and CH 2 DC, AC, or GND Volts/Div setting 2 mV/div ­ 99.5 mV/div 100 mV/div ­ 995 mV/div 1 V/div ­ 10 V/div Range, Position Range, Sensitivity2 Rise Time ±5 divisions 2 mV/div to 10 V/div TDS 340A: 3.5 ns TDS 360: 1.75 ns TDS 380: 875 ps Level one probe coding Offset range ±1 V ±10 V ±100 V

TekProbe Interface
1

Displayed vertically with 25 digitization levels (DLs) per division and 10.24 divisions dynamic range with zoom off. A DL is the smallest voltage level change that the 8-bit A-D Converter can resolve, with the input scaled to the volts/division setting of the channel used. Expressed as a voltage, a DL is equal to 1/25 of a division times the volts/division setting. The sensitivity ranges from 2 mV/div to 10 V/div in a 1­2­5 sequence of coarse settings. Between consecutive coarse settings, the sensitivity can be finely adjusted with a resolution of 1% of the more sensitive setting. For example, between 50 mV/div and 100 mV/div, the volts/division can be set with 0.5 mV resolution.

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Table 1­11: Nominal traits -- time base system
Name Range, Sample-Rate1,2 Description TDS 340A: 10 Samples/s to 500 MSamples/s in a 1­2­5 sequence TDS 360: 10 Samples/s to 1 GSamples/s in a 1­2­5 sequence TDS 380: 10 Samples/s to 2 GSamples/s in a 1­2­5 sequence TDS 340A: 5 ns/div to 5 s/div in a 1­2.5­5 sequence TDS 360: 2.5 ns/div to 5 s/div in a 1­2.5­5 sequence TDS 380: 1 ns/div to 5 s/div in a 1­2.5­5 sequence 16.5 ns to 50 seconds 1,000 samples

Range, Seconds/Division

Range, Time Base Delay Time Record Length
1

The range of real-time rates, expressed in samples/second, at which a digitizer samples signals at its inputs and stores the samples in memory to produce a record of time-sequential samples The Waveform Rate (WR) is the equivalent sample rate of a waveform record. For a waveform record acquired by real-time sampling of a single acquisition, the waveform rate is the same as the real-time sample rate; for a waveform created by interpolation of real-time samples from a single acquisition or by equivalent-time sampling of multiple acquisitions, the waveform rate is faster than the real time sample rate. For all three cases, the waveform rate is 1/(Waveform Interval) for the waveform record, where the waveform interval (WI) is the time between the samples in the waveform record.

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Table 1­12: Nominal traits -- triggering system
Name Range, Hold Off Ranges, Trigger Level Description 500 ns minimum to 10 seconds maximum Source Any Channel External External /10 Line Formats and Field Rates, Video Trigger Range ±12 divisions from center of screen ±1.5 Volts ±15 Volts ±300 Volts

Triggers from sync-negative composite video, 525 to 625 lines, 50 Hz to 60 Hz, interlaced or noninterlaced systems with scan rates from 15 kHz to 65 kHz ­ such as NTSC, PAL, or SECAM Level one probe coding

TekProbe Interface, External Trigger

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Table 1­13: Nominal traits -- display system
Name CRT Type Video Display Resolution Description 7-inch (17.95 cm) diagonal, magnetic deflection; horizontal raster-scan; P31 green phosphor 640 pixels horizontally by 480 pixels vertically Display area is 5.04 inch (12.92 cm) horizontally by 3.78 inch (9.69 cm) vertically Waveform Display Graticule Intensity Levels A single graticule 401 × 501 pixels (8 × 10 divisions, with divisions that are approximately 1 cm by 1 cm) Dim and Bright, with adjustable Overall Intensity and Contrast

Table 1­14: Nominal traits -- I/O interface option
Name GPIB RS-232 Centronics Description Part of Option 14 I/O interface or TD3F14A I/O interface field upgrade kit; complies with IEEE Std 488­1987 Part of Option 14 I/O interface or TD3F14A I/O interface field upgrade kit; a 9-pin male DTE RS-232 interface that complies with EIA/TIA 574­90 Part of Option 14 I/O interface or TD3F14A I/O interface field upgrade kit; a 25-pin, IBM PC-type, parallel printer interface that complies electrically with Centronics C332­44, Rev A DB-9 rear panel Video connector; non-interlaced, with levels that comply with ANSI RS343A VGA compatible at a 30.6 kHz sync rate Power Supply, Printer (Option 14 Only) Power supply connector to supply power to the Option 3P Printer Pack

Video Signal Output (Option 14 Only)

Table 1­15: Nominal traits -- power distribution system
Name Fuse Rating Description 5 mm × 20 mm, 3.15 A (T), 250 V; or 1.25 in × 0.25 in, 3 A (T), 250 V

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Table 1­16: Nominal traits -- mechanical characteristics
Name Weight Standard 7.0 kg (15.5 lbs) stand-alone instrument; 8.6 kg (19 lbs) with front cover, accessories, and accessories pouch installed; 12.9 kg (28.5 lbs) when packaged for domestic shipment 6.6 kg (14.5 lbs), plus weight of rackmount parts (Option 1R); 14.7 kg (32.5 lbs) when the oscilloscope is packaged for domestic shipment 4.5 kg (10 lbs); 7.5 kg (17.5 lbs) when kit is packaged for domestic shipment Height: Width: Depth: 191 mm (7.5 in) with feet and accessories pouch installed 165 mm (6.5 in) without the accessories pouch installed 362 mm (14.25 in) with handle 471 mm (18.55 in) stand-alone instrument 490 mm (19.28 in) with front cover installed 564 mm (22.2 in) with handle extended Description

Rackmount Rackmount conversion kit Overall Dimensions Standard Instrument (Figure 1­1)

Rackmount Instrument

Height: 178 mm (7 in) Width: 483 mm (19 in) Depth: 472 mm (18.6 in) without handles; 517 mm (20.35 in) including handles

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471 mm (18.55 in.)

327.2 mm (12.88 in.)

165 mm (6.5 in.) 308.1 mm (12.13 in.)

569 mm (22.4 in.)

381 mm (15 in.)

Figure 1­1: TDS 340A, TDS 360, & TDS 380 dimensions

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Table 1­17: Certifications and compliances
EC Declaration of Conformity Meets intent of Directive 89/336/EEC for Electromagnetic Compatibility and Low Voltage Directive 73/23/EEC for Product Safety. Compliance was demonstrated to the following specifications as listed in the Official Journal of the European Communities: EMC Directive 89/336/EEC: EN 55011 EN 50081-1 Emissions: EN 60555-2 EN 50082-1 Immunity: IEC 801-2 IEC 801-3 IEC 801-4 IEC 801-5 Class B Radiated and Conducted Emissions 1 AC Power Line Harmonic Emissions Electrostatic Discharge Immunity RF Electromagnetic Field Immunity 2 Electrical Fast Transient/Burst Immunity Power Line Surge Immunity

Low Voltage Directive 73/23/EEC: EN 61010-1 Safety requirements for electrical equipment for measurement, control, and laboratory use
1

To maintain emission requirements when connecting to the I/O interface of this oscilloscope, use only a high-quality, double-shielded (braid and foil) cable. The cable shield must have low-impedance connections to both connector housings. The VGA cable must also have a ferrite core at both ends. Acceptable cables are listed in Table 7­6 on page 7­4. Performance criteria: ±0.3 division waveform displacement, or 0.6 division increase in p-p noise from 27 MHz to 500 MHz. Test conditions: both channel inputs terminated with grounding caps, both channels set to 10 mV/div, both channels set to DC Coupling, trigger source set to CH 1, acquisition mode set to Sample, and time base set to 250 ms/div.

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Certifications

Underwriters Laboratories listing to Standard UL3111­1 for Electrical Measuring and Test Equipment. 3 4 Canadian Standards Association certified to Standard CAN/CSA-C22.2 No. 1010.1­92. 3
3 4

These standards are North American interpretations of IEC 1010. Conditions for certification: operating temperature ­10_ C to +55_ C, maximum operating altitude 2000 m, Safety Class I (IEC 1010-1 Annex H), Overvoltage Catagory II (IEC 1010-1 Annex J), Pollution Degree 2 (IEC 1010-1).

FCC Compliance CSA Certified Power Cords Overvoltage Category

Emissions comply with FCC Code of Federal Regulations 47, Part 15, Subpart B, Class A Limits CSA Certification includes the products and power cords appropriate for use in the North America power network. All other power cords supplied are approved for the country of use. Category: CAT III CAT II CAT I Examples of Products in this Category: Distribution-level mains, fixed installation Local-level mains, appliances, portable equipment Signal levels in special equipment or parts of equipment, telecommunications, electronics

Pollution Degree 2

Do not operate in environments where conductive pollutants may be present.

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Operating Information
This section identifies and describes each control and connector on the TDS 300 Series oscilloscope. This chapter also describes how to use the oscilloscope menu system. Refer to the TDS 340A, TDS 360 & TDS 380 User Manual for more information on setting up and taking measurements with the oscilloscope.

Display and Power Controls

The Side Menu buttons provide access to side menu selections. Refer to page 2­7 for more information about the user interface Side Menu.

The CLEAR MENU button clears all menus from the screen.

The ON/STBY button toggles instrument power.

The Main Menu buttons provide access to main menu selections. Refer to page 2­7 for more information about the user interface Main Menu.

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Vertical Controls

The Vertical POSITION knob controls the vertical position of the selected waveform. The Waveform Select buttons display and select waveforms (CH1, CH2, MATH, REF1, and REF2). A light next to a button illuminates when that waveform is selected.

The VERTICAL MENU button calls up the vertical operations menu.

Connector to chassis ground.

The SCALE knob controls the vertical scale of the selected waveform. Probe compensation output. The WAVEFORM OFF button turns off the selected waveform.

Horizontal Controls

The Horizontal POSITION knob controls the horizontal position of all waveforms. The HORIZONTAL MENU button calls up the horizontal operations menu.

The SCALE knob controls the horizontal scale of the active waveforms.

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Trigger Controls
The Trigger LEVEL knob controls the trigger. The TRIGGER MENU button calls up the trigger menu. The SET LEVEL TO 50% button sets the trigger level at the midpoint between the peaks of the trigger signal.

The FORCE TRIGGER button forces the oscilloscope to start acquiring a waveform regardless of whether a trigger event occurs. This button has no effect if the acquisition system is stopped.

The trigger status lights indicate the status of the triggering system. The TRIG'D light illuminates when the instrument recognizes a valid trigger. The READY light illuminates when the instrument can accept a valid trigger and is waiting for that event to occur.

Inputs

The channel BNC inputs (CH1 and CH2) accept electrical signals for display.

The EXT TRIG input accepts external trigger signals.

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Miscellaneous Controls
The MEASURE button calls up the automated measurements menu.

The UTILITY button calls up the utility menu.

The floppy disk drive provides mass storage for waveforms, setups, and hard copies.

The RUN/STOP button starts and stops acquisition.

The AUTOSET button automatically sets up the instrument to produce a usable display of the input signals.

The HARDCOPY button starts print operations. (Requires Opt 14 installed)

The General Purpose Knob controls many side-menu functions, including the cursors. The SELECT button switches control from cursor to cursor.

The ACQUIRE button calls up the acquisition menu.

The SAVE/RECALL button calls up the save/recall menu.

The CURSOR button calls up the cursor menu.

The DISPLAY button calls up the display menu.

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Display Map

Trigger position (T).

Indicates position of vertical bar cursors in the waveform record.

The waveform record icon.

Shows what part of the waveform record is displayed.

The value entered with the general purpose knob. When the general purpose knob is first assigned, the knob icon appears here.

The Status Readouts show trigger status and acquisition status (mode and sampling rate or number of acquisitions).

Trigger level indicator Trigger point indicator Channel ground indicator

Cursor measurement readouts.

The side menu offers a choice of specific actions.

The Channel readout shows the vertical scale of all active channels.

The Trigger readout shows the trigger source and level and whether the oscilloscope is triggered on the rising or falling edge of the waveform. When in video-trigger mode, the readout displays source and trigger feature (Field 1, Field 2, or Lines).

The main menu offers a choice of major actions.

The Time base readout shows the time base setting. M indicates (M)ain time base, D indicates (D)elayed time base.

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Rear-Panel Connectors

The Option 14 Panel (Option 14 instruments only) allows access to three communications interfaces: a Centronics parallel port, an RS-232 interface, and a GPIB interface. It also includes a VGA video-compatible output port and a power connector for the optional TDS4F5P printer upgrade kit. You can use the Centronics, RS-232, and GPIB interfaces to transmit hardcopy data. You can use the GPIB and RS-232 interfaces to operate and program the oscilloscope from a GPIB or RS-232 controller; see the TDS 340A, TDS 360 & TDS 380 Programmer Manual for more information.

The power connector accepts line voltage to power the instrument. Refer to page 7­2 for a list of power cord and connector options. The fuse drawer holds the line fuse. Refer to page 6­8 for fuse replacement procedures.

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Using the Menu System
TDS 300 Series oscilloscopes use an intuitive user interface. This interface reduces front-panel clutter while allowing easy access to specialized functions through the menu structure. The following procedure describes how to navigate in the menu structure. If you are unfamiliar with this menu system, you may want to run through the procedure several times to learn how you can access functions and subfunctions. Figure 2­2 provides a graphic overview of using the menu system.

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Operating Information

1. Push a front-panel button to call up a menu of functions. This first menu is the main menu. Sometimes the main menu will be a side menu (step 3), but most main menus are bottom menus. 2. Push a main menu button to select a function. One of three things happens: H If the function has no subfunctions, it becomes active. If it is a variable function, you can now use the General Purpose Knob to adjust it (step 4). If the function has subfunctions, they appear on the side menu (step 3). The leftmost main menu button sometimes activates a pop-up menu (as shown in Figure 2­1). You can cycle through the pop-up menu options by repeatedly pressing the button. Each selection calls up different main and side menus.

H H

Figure 2­1: A pop-up menu 3. Push a side-menu button to select a subfunction. 4. Use the General Purpose knob to change variable-function or subfunction settings. 5. Press the CLEAR MENU button to remove a menu from the screen.

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TDS 340A, TDS 360 & TDS 380 Service Manual

Operating Information

1 Press any of the front-panel menu buttons.

2 Select an item from the main menu
or use leftmost button to pop up selections.

3 Select an item from the side menu, if displayed.

4 Adjust menu item values with general purpose knob.

Figure 2­2: Using menus

TDS 340A, TDS 360 & TDS 380 Service Manual

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Operating Information

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TDS 340A, TDS 360 & TDS 380 Service Manual

Theory of Operation
This section describes the electrical operation of the TDS 340A, TDS 360, and TDS 380 to the module level.

Logic Conventions
This manual refers to digital logic circuits with standard logic symbols and terms. Unless otherwise stated, all logic functions are described using the positive logic convention: the more positive of the two logic levels is the high (1) state and the more negative level is the low (0) state. Signal states may also be described as "true" meaning their active state or "false" meaning their non-active state. The specific voltages that constitute a high or low state vary among the electronic devices. Active-low signals are indicated by a tilde (~) prefixed to the signal name (~RESET). Signal names are considered to be either active-high, active-low, or to have both active-high and active-low states.

Module Overview
This overview describes the basic operation of each functional circuit block as shown in Figures NO TAG through 3­2.

Input Signal Path

A signal enters the oscilloscope through a probe connected to a BNC on the A11 (TDS 340A), A12 (TDS 360), or A13 (TDS 380) Main Board. Attenuators. Circuitry in the attenuator selects the input coupling and attenuation factor. The processor system controls the attenuators with a serial interface. Probe Coding Interface. The probe coding interface signals pass through the Main Board to the A6 Front Panel, which senses them. Acquisition System. The acquisition system amplifies the input signals, samples them, converts them to digital signals, and controls the acquisition process under direction of the processor system. The acquisition system includes the trigger, acquisition timing, and acquisition mode generation and control circuitry.

TDS 340A, TDS 360 & TDS 380 Service Manual

3­1

Theory of Operation

A20 LV Power A9 Bezel Button Flex
10 Pins P1 Supply 2 Pins J3 P3 J2 P2 2 Fan

A6
Front Panel

J40 10 Pins

2 Pins J1 13 Pins P1

J35 4 Pins J84 5 Pins Not Used Cal Sig 13

A11 (TDS 340A) Main A12 (TDS 360) A13 (TDS 380)
J603 16 Pins J702 13 Pins J702 8 Pins

2

J30 16 Pins

P30 16

P603

A26 Monitor
J901 8 10 Pins

J53 CH1 J605 J52 CH2 J606 J51 EXT TRIG J607 J602 50 Pins

A5 Floppy interface
board JR3 50 Pins J1 26 Pins 26

Floppy disk drive J1 26 Pins

Figure 3­1: TDS 340A, TDS 360, & TDS 380 block diagram

3­2

TDS 340A, TDS 360 & TDS 380 Service Manual

Theory of Operation

A20 LV Power A9 Bezel Button Flex
10 Pins P1 Supply 2 Pins

J2 J4 2 Pins J3

P2 P4 P3

2 2

Fan

A3 Option 14
Printer Power J1 J4 2 Pins 6 Pins J3 9 Pins VGA J2 PWR

2 Pins

A6
Front Panel

J40 10 Pins

2 Pins J1 13 Pins P1

6

J35 4 Pins J84 5 Pins Not Used Cal Sig 13

A11 (TDS340A) Main A12 (TDS 360) A13 (TDS 380) J702
13 Pins J603 16 Pins J703 6 Pins P703

2

J30 16 Pins

P30 16

P603

A26 Monitor
J901

J701 8 Pins

8

10 Pins

J53 CH1 J605 J52 CH2 J606 J51 EXT TRIG J607 P601 J601 50 Pins

A5 Floppy interface
board JR3 50 Pins 26 Pins 26

Floppy disk drive J1 26 Pins

J2 50 Pins

A2
Option 14 I/O Interfaces 50 J1 50 Pins

J2 9 Pins J4 25 Pins J3 CENTRONICS GPIB RS232

50 Terminations 25 Pins

Figure 3­2: TDS 340A, TDS 360, and TDS 380 with Option 14 block diagram

TDS 340A, TDS 360 & TDS 380 Service Manual

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Theory of Operation

Processor System. The processor system contains a 68331 microprocessor that controls the entire instrument. The processor passes waveforms and text on to the display system. The Main Board contains both the processor and display systems, in addition to the firmware ROMs. Display System. A display controller IC processes text and waveforms. The display system sends the text and waveform information to the monitor assembly as a video signal. The display system also generates and sends vertical (VSYNC) and horizontal (HSYNC) sync signals to the monitor assembly.

Monitor

All information (waveforms, text, graticules, and pictographs) is displayed by the A26 Monitor. It generates the high voltages necessary to drive the display tube. It also contains the video amplifier, horizontal oscillator, and the vertical and horizontal yoke driver circuitry. The processor system sends instructions to and receives information from the Front Panel Processor on the Front Panel Board. The Front Panel Processor reads the front-panel switches and ports, and reports any change in their settings to the processor system. The Front Panel Processor also turns front panel LEDs on and off. The Front Panel Processor reads the front-panel menu switches and sends any changes in menu selections to the processor system. The ON/STBY button is not read by the Front Panel Processor but passes through the Front Panel Board and the Main Board to the A20 Low Voltage Power Supply. The front panel also generates the probe compensation signal.

Front Panel

Floppy Disk Drive

The floppy disk drive system consists of the A5 floppy interface board that connects to the main board. A 26-pin cable connects the floppy disk drive to the floppy interface board, supplying both power and data to the drive. The drive is 2 Mbyte double-side, high-density unit that uses 3.5 inch IBM-format disks.

Option 14

The A2 Option 14 board has GPIB, RS-232, and Centronics interfaces for external control and hardcopy operations. Also included is the A3 board with a VGA video output port and a power connector for the Option 3P printer.

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TDS 340A, TDS 360 & TDS 380 Service Manual

Theory of Operation

Low Voltage Power Supply

The A20 Low Voltage Power Supply is a switching power converter. It supplies power to all the circuitry in the oscilloscope. The Low Voltage Power Supply does not have a main power switch. The ON/STBY switch, located on the front panel, controls all the power to the oscilloscope except the standby circuits in the Low Voltage Power Supply.

Fan

The fan provides forced air cooling for the oscilloscope. It connects to a 12 V connector on the Low Voltage Power Supply.

TDS 340A, TDS 360 & TDS 380 Service Manual

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Theory of Operation

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TDS 340A, TDS 360 & TDS 380 Service Manual

Performance Verification
The procedures in this section verify that the TDS 340A, TDS 360, and TDS 380 oscilloscopes meet warranted specifications. There are three performance tests that you can do. H To rapidly confirm that this oscilloscope functions, do the Self Test procedures that begin on page 4­5. Advantages: This procedure is quick to do, requires no external equipment or signal sources, and performs extensive functional and accuracy testing to provide high confidence that the oscilloscope performs properly. You can use it as a quick check before making a series of important measurements. H To further check functionality, do the Functional Test procedures that begin on page 4­7. Advantages: These procedures require minimal additional time to perform, require no additional equipment other than a standard-accessory probe, and more completely test the internal hardware of this oscilloscope. You can use them to quickly determine if the oscilloscope is suitable for putting into service, such as when it is first received. H If you need a more extensive confirmation of performance, do the Performance Tests that begin on page 4­11, after doing the functional and self tests. Advantages: These procedures check warranted specifications. They require more time and suitable test equipment. (See Test Equipment on page 4­3.)

Conventions
Throughout these procedures the following conventions apply: H Each test procedure uses the following general format: Title of test Equipment required Time required Prerequisites Procedure steps

TDS 340A, TDS 360 & TDS 380 Service Manual

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Performance Verification

H

Refer to Figure 4­1: "Main menu" refers to the menu that labels the seven menu buttons under the display. "Side menu" refers to the menu that labels the five buttons to the right of the display. "Pop-up menu" refers to a menu that pops up when a main menu button is pressed. Where instructed to use a front-panel button or knob, select from a main or side menu, or verify a readout or status message, the name of the button or knob appears in boldface type. Instructions for menu selection follow this format: FRONT PANEL BUTTON ! Pop-Up (if necessary) ! Main Menu Button ! Side Menu Button. For example, "Push TRIGGER MENU ! Type: Video ! Trigger On ! Lines."

H

H

STOP. This symbol denotes information you must read to do the procedure properly.

Side Menu

Pop-Up Menu

Main Menu

Figure 4­1: Menu locations

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TDS 340A, TDS 360 & TDS 380 Service Manual

Performance Verification

Test Equipment
The performance test procedures require external, traceable signal sources to check instrument performance. If your test equipment does not meet the minimum requirements listed in Table 4­1, your test results will be invalid. Table 4­1: Test equipment
Item number and description 1. Termination 50 W (two required) Cable, Precision Coaxial (two required) Connector, Dual-Banana Connector, BNC "T" Coupler, Dual-Input Generator, DC Calibration Minimum requirements Impedance 50 W; connectors: female BNC input, male BNC output 50 W, 91 cm (36 in), male to male BNC connectors Female-BNC to dual-banana Male-BNC to dual-female-BNC Female-BNC to dual-male-BNC Variable amplitude to ±110 V; accuracy to 0.1% 50 kHz to 250 MHz; variable amplitude from 5 mV to 4 Vp-p into 50 W 50 kHz to 400 MHz; variable amplitude from 5 mV to 4 Vp-p into 50 W Variable marker frequency from 10 ms to 10 ns; accuracy within 2 ppm A P6109B (TDS 340A), P6111B (TDS 360), or P6114B (TDS 380) probe Example Tektronix part number 011-0049-01 Tektronix part number 012-0482-00 Tektronix part number 103-0090-00 Tektronix part number 103-0030-00 Tektronix part number 067-0525-02 Wavetek 9100 Calibration System with Option 250 and Option 100 Wavetek 9100 Calibration System with Option 250 and Option 100 Rohde & Schwarz SMY with URV 35 Power Meter and NRV-Z8 Power Sensor Wavetek 9100 Calibration System with Option 250 and Option 100 Tektronix number P6109B (TDS 340A), P6111B (TDS 360), or P6114B (TDS 380) Purpose Checking delay between channels Signal interconnection Several accuracy tests Checking trigger sensitivity Checking delay between channels Checking DC offset, gain, and measurement accuracy Checking bandwidth and trigger sensitivity Checking bandwidth and trigger sensitivity Checking sample rate and delay-time accuracy Signal interconnection

2. 3. 4. 5. 6.

7.

Generator, Leveled Sine Wave, Medium-Frequency Generator, Leveled Sine Wave, High-Frequency1 Generator, Time Mark

8.

9.

10. Probe, 10X, included with this instrument
1

The high frequency leveled sine wave generator is only required to verify the TDS 380, not the TDS 340A or TDS 360. If you use the e