Tektronix TDS 820 User manual

Performance Verification
TDS 820
Digitizing Oscilloscope
070-8696-00
Please check for change information at the
rear of this manual.
First Printing: February 1993

Instrument Serial Numbers
Each instrument manufactured by Tektronix has a serial number on a panel insert or tag, or stamped on the
chassis. The first letter in the serial number designates the country of manufacture. The last five digits of the
serial number are assigned sequentially and are unique to each instrument. Those manufactured in the United
States have six unique digits. The country of manufacture is identified as follows:
B010000 Tektronix, Inc., Beaverton, Oregon, USA
E200000 Tektronix United Kingdom, Ltd., London
J300000 Sony/Tektronix, Japan
H700000 Tektronix Holland, NV, Heerenveen, The Netherlands
Instruments manufactured for Tektronix by external vendors outside the United States are assigned a two digit
alpha code to identify the country of manufacture (e.g., JP for Japan, HK for Hong Kong, IL for Israel, etc.).
Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077
Printed in U.S.A.
Copyright E Tektronix, Inc., 1993. All rights reserved. Tektronix products are covered by U.S. and foreign
patents, issued and pending. The following are registered trademarks: TEKTRONIX, TEK, TEKPROBE, and
SCOPE-MOBILE.

WARRANTY
Tektronix warrants that this product will be free from defects in materials and workmanship for a period of three (3) years from
the date of shipment. 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.
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, with shipping charges prepaid.
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.
This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate
maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting
from attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to repair damage
resulting from improper use or connection to incompatible equipment; or c) to service a product that has been modified or
integrated with other products when the effect of such modification or integration increases the time or difficulty of servicing
the product.
THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THIS PRODUCT IN LIEU OF ANY OTHER
WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’ RESPONSIBILITY TO REPAIR OR
REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR
BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT,
SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE
VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

TDS 820 Performance Verification
i
Preface
This is the Performance Verification for the TDS 820 Oscilloscope. It contains
procedures suitable for determining if the instrument functions, was adjusted
properly, and meets the performance characteristics as warranted.
Also contained in this document is a copy of the
Specification found in Appen-
dix B of the
TDS 820 User Manual . It is included here as a convenient refer-
ence.
The following documents are related to the use or service of the digitizing
oscilloscope.
H The
TDS 820 User Manual .
H The
TDS 800 Series Family Programmer Manual describes using a
computer to control the digitizing oscilloscope through the GPIB interface.
H The
TDS 820 Reference gives you a quick overview of how to operate
your digitizing oscilloscope.
H The
TDS 820 Service Manual provides information for maintaining and
servicing your digitizing oscilloscope to the module level.
H The
TDS Family Option 2F Instruction Manual describes use of the
Advanced DSP Math option (for TDS oscilloscopes equipped with that
option only).
H The
TDS Family Option 13 Instruction Manual describes using the option-
al Centronic TDS
oscilloscopes equipped with that option only).
Related Manuals

Preface
ii

TDS 820 Performance Verification
iii
Contents
Safety v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Performance Verification
Procedures
Brief Procedures 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Instructions 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conventions 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Self Tests 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Verify Internal Adjustment, Self Compensation, and
Diagnostics 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Functional Tests 1-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Verify All Input Channels 1-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Verify the Time Base 1-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Verify the Trigger System 1-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Performance Tests 1-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Prerequisites 1-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Equipment Required 1-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test Record 1-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Signal Acquisition System Checks 1-17. . . . . . . . . . . . . . . . . . . . . . . .
Check Accuracy of Net Offset 1-17. . . . . . . . . . . . . . . . . . . . . . . . . . .
Check Voltage Measurement Accuracy 1-21. . . . . . . . . . . . . . . . . . .
Check Rise Time 1-26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Check Input Resistance 1-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Time Base System Checks 1-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Check Accuracy of Delta Time Measurement Between
Channels 1-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Check Accuracy of Single Channel Delta Time
Measurements 1-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Trigger System Checks 1-42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Check Accuracy, Trigger-Level 1-42. . . . . . . . . . . . . . . . . . . . . . . . . .
Sensitivity, Trigger, External, CH 1, and CH 2 1-45. . . . . . . . . . . . .
Check Trigger Delay Jitter and Random Noise 1-48. . . . . . . . . . . .

Contents
i
Specifications
Product Description 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nominal Traits 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Warranted Characteristics 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Performance Conditions 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Typical Characteristics 2-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TDS 820 Performance Verification
v
Safety
Please take a moment to review these safety precautions. They are for your
protection and to prevent damage to the digitizing oscilloscope. This safety
information applies to all operators and service personnel.
These two terms appear in manuals:
H
statements identify conditions or practices that could result in
damage to the equipment or other property.
H
statements identify conditions or practices that could result in
personal injury or loss of life.
These two terms appear on equipment:
H
CAUTION indicates a personal injury hazard not immediately accessible
as one reads the marking, or a hazard to property including the equip-
ment itself.
H
DANGER indicates a personal injury hazard immediately accessible as
one reads the marking.
This symbol appears in manuals:
Static-Sensitive Devices
These symbols appear on equipment:
DANGER
High Voltage Protective ground (earth)
terminal
ATTENTION
Refer to
manual
Symbols and Terms

Safety
vi
Observe all of these precautions to ensure your personal safety and to pre-
vent damage to either the digitizing oscilloscope or equipment connected to it.
Power Source
The digitizing oscilloscope operates from a power source that will not apply
more than 250 Vrms between the supply conductors or between either supply
conductor and ground. A protective ground connection, through the grounding
conductor in the power cord, is essential for safe system operation.
Grounding the Digitizing Oscilloscope
The digitizing oscilloscope is grounded through the power cord. To avoid
electric shock, plug the power cord into a properly wired receptacle where
earth ground has been verified by a qualified service person. Do this before
making connections to the input or output terminals of the digitizing oscillo-
scope.
Without the protective ground connection, all parts of the digitizing oscillo-
scope are potential shock hazards. This includes knobs and controls that may
appear to be insulators.
Use the Proper Power Cord
Use only the power cord and connector specified for your product. Use only a
power cord that is in good condition.
Use the Proper Fuse
To avoid fire hazard, use only the fuse specified in the parts list for your
product, matched by type, voltage rating, and current rating.
Do Not Remove Covers or Panels
To avoid personal injury, do not operate the digitizing oscilloscope without the
panels or covers.
Take Antistatic Precautions
Wear an antistatic grounding wrist strap when working with the input connec-
tors on the digitizing oscilloscope.
Electric Overload
Never apply to a connector on the digitizing oscilloscope a voltage that is
outside the range specified for that connector.
Specific Precautions

Safety
TDS 820 Performance Verification
vii
Do Not Operate in Explosive Atmospheres
The digitizing oscilloscope provides no explosion protection from static dis-
charges or arcing components. Do not operate the digitizing oscilloscope in
an atmosphere of explosive gases.

Safety
viii

Performance Verification
Procedures

TDS 820 Performance Verification
1Ć1
Brief Procedures
The Self Tests use internal routines to confirm basic functionality and proper
adjustment. No test equipment is required to do these test procedures.
The
Functional Tests utilize the 1 MHz Test Signal output at the rear panel as
a test-signal source for further verifying that the oscilloscope functions
properly. Standard-accessory SMA cables, included with this oscilloscope, are
the only equipment required.
Besides the
Brief Procedures, the set of procedures that can be used to verify
oscilloscope performance includes the
Performance Tests, found later in this
section. You may not need to perform all of these procedures, depending on
what you want to accomplish:
H To rapidly confirm that this oscilloscope functions and was adjusted
properly, just do the procedures under
Self Tests , which begin on
page 1-3.
Advantages: These procedures are quick to do, require no external
equipment or signal sources, and perform extensive functional and accu-
racy testing to provide high confidence that the oscilloscope will perform
properly. They can be used as a quick check before making a series of
important measurements.
H To further check functionality, first do the
Self Tests just mentioned; then
do the procedures under
Functional Tests that begin on page 1-5.
Advantages: These procedures require minimal additional time to per-
form, require no additional equipment other than standard-accessory
SMA cables, and more completely test the internal hardware of this
oscilloscope. They can be used to quickly determine if the oscilloscope is
suitable for putting into service, such as when it is first received.
H If more extensive confirmation of performance is desired, do the
Perfor-
mance Tests
, beginning on page 1-11, after doing the Functional and Self
Tests
just referenced.
Advantages: These procedures add direct checking of warranted specifi-
cations. They require more time to perform and suitable test equipment is
required. (See
Equipment Required on page 1-12.)
If you are not familiar with operating this oscilloscope, read
General Operating
Instructions
in Section 3 of this manual. These instructions will acquaint you
with the use of the front-panel controls and the menu system.
If you are not familiar with operating this oscilloscope, read
At a Glance in
Section 2 of the TDS 820 User Manual .
General Instructions

Brief Procedures
Appendix C: Performance Verification
Performance Verification
1Ć2
Throughout these procedures the following conventions apply:
H Tighten all SMA connectors to 8.5 inch pounds (0.96 N · m).
H Each test procedure uses the following general format:
Title of Test
Equipment Required
Prerequisites
Procedure
H Each procedure consists of as many steps, substeps, and subparts as
required to do the test. Steps, substeps, and subparts are sequenced as
follows:
1. First Step
a. First Substep
H First Subpart
H Second Subpart
b. Second Substep
2. Second Step
H In steps and substeps, the lead-in statement in italics instructs you what
to do, while the instructions that follow tell you how to do it: in the exam-
ple step below,
“Initialize the oscilloscope” by doing “Press save/recall
SETUP. Now, press the main-menu button.”
Initialize the oscilloscope: Press save/recall SETUP. Now, press the
main-menu button Recall Factory Setup; then the side-menu button
OK Confirm Factory Init.
H Where instructed to use a front-panel button or knob, or 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: “press SHIFT; then AC-
QUIRE MENU”, “press the main-menu button Slope”, or “verify that the
status message is
Pass ”.
The symbol at the left is accompanied by information you must read
to do the procedure properly.
Conventions

Brief Procedures
Appendix C: Performance Verification
TDS 820 Performance Verification
1Ć3
H Refer to Figure 1-1: “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 the when a main-menu button is pressed.
Brief Status
Information
Position of Waveform
Record Relative to
the Screen and Display
General Purpose
Knob Readout
Waveform Reference
Symbols:GroundLevels
and Waveform Sources
GraticuleandWaveforms
Side menu area.
Readouts for
measurements
move here when
CLEAR MENU is
pressed.
Main menu display area. Readouts in
lower graticule area move here when
CLEAR MENU is pressed.
Pop-up Menu
Vertical Scale,
Horizontal Scale, and
Trigger Level Readouts
Figure 1-1: Map of Display Functions
This procedure uses internal routines to verify that this oscilloscope functions
and was adjusted properly. No test equipment or hookups are required.
Verify Internal Adjustment, Self Compensation, and
Diagnostics
Equipment Required: None.
Prerequisites:
Power up the digitizing oscilloscope and allow a 20 minute
warm-up before doing this procedure.
Self Tests

Brief Procedures
Appendix C: Performance Verification
Performance Verification
1Ć4
Procedure:
1.
Verify that internal diagnostics pass: Do the following substeps to verify
passing of internal diagnostics.
a.
Display the System diagnostics menu:
H Press SHIFT; then press UTILITY.
H Repeatedly press the main-menu button System until Diag/Err is
highlighted in the pop-up menu.
b.
Display the Area diagnostics menu: Repeatedly press the main-menu
button Area until All is highlighted in the pop-up menu.
Remove all input signals from the inputs.
c.
Run the System Diagnostics: Press the main-menu button Execute;
then press the side-menu button OK Confirm Run Test.
d.
Wait: The internal diagnostics do an exhaustive verification of proper
oscilloscope function. When finished, the resulting status will appear
on the screen.
e.
Confirm no failures are found: Verify that no failures are found and
reported on-screen.
First, the CAL menu is displayed.
Second, a signal path
compensation is run
and is verified.
Figure 1-2: Verifying Adjustments and Signal-Path Compensation
f. Run the signal-path compensation:
H Press SHIFT; then press UTILITY.

Brief Procedures
Appendix C: Performance Verification
TDS 820 Performance Verification
1Ć5
H Press the main menu button System until Cal is highlighted in
the pop-up menu.
H Press the main-menu button Comp All; then press the side-
menu button OK Compensate All.
g.
Wait: Signal-path compensation runs in about thirty seconds. While it
progresses, a “clock” icon (shown at left) is displayed on-screen.
When compensation completes, the status message will be updated
to
Pass or Fail in the main menu (see step h).
h.
Confirm signal-path compensation returns passed status: Verify the
word
Pass appears under Comp All in the main menu. (See Fig-
ure 1-2.)
2.
Return to regular service: Press CLEAR MENU to exit the system me-
nus.
The purpose of these procedures is to confirm that this oscilloscope functions
properly. The only equipment required is one of the standard-accessory SMA
cables.
These procedures verify functions; that is, they verify that oscillo-
scope features
operate . They do not verify that they operate within
limits.
Therefore, when the instructions in the functional tests that follow call
for you to verify that a signal appears on-screen “that is about five
divisions in amplitude” or “has a period of about six horizontal divi-
sions”, etc., do
NOT interpret the quantities given as limits. Operation
within limits is checked in
Performance Tests , which begin on
page 1-11.
DO NOT make changes to the front-panel settings that are not called
out in the procedures. Each verification procedure will require you to
set the oscilloscope to certain default settings before verifying func-
tions. If you make changes to these settings, other than those called
out in the procedure, you may obtain invalid results. In this case, just
redo the procedure from step 1.
When you are instructed to press a menu button, the button may
already be selected (its label will be highlighted). If this is the case, it
is not necessary to press the button.
Verify All Input Channels
Equipment Required: Three SMA cables and a T connector.
Prerequisites: None.
Procedure:
1.
Install the test hookup and preset the oscilloscope controls:
Functional Tests

Brief Procedures
Appendix C: Performance Verification
Performance Verification
1Ć6
SMA T
Connector
Antistatic Grounding
Wrist Strap
To 1 MHz TEST
SIGNAL OUTPUT
on Rear Panel
Figure 1-3: Universal Test Hookup for Functional Tests
CAUTION
Inputs to this oscilloscope can be damaged by static discharge.
Wear your antistatic wrist strap whenever making connections the
oscilloscope.
a. Hook up the signal source: Connect one end of an SMA cable to the
1 MHz TEST SIGNAL OUTPUT on the rear panel. Connect the other
end of the cable to the T connector. Connect the T connector, through
SMA cables, to the CH 1 input and the EXT TRIGGER INPUT on the
front panel.
b.
Initialize the oscilloscope:
H Press save/recall SETUP.
H Press the main-menu button Recall Factory Setup.
H Press the side-menu button OK Confirm Factory Init.
2.
Verify that all input channels operate: Do the following substeps — test
CH 1 first, skipping substep a since CH 1 is already set up for verification
from step 1.
a. Select an unverified channel:
H Press WAVEFORM OFF to remove from display the channel just
verified.
H Press the front-panel button that corresponds to the channel you
are to verify.
H Move the SMA cable to the channel you selected.