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THS 710 & THS 720
TekScopeTM
User Manual
070-9247-02




This document applies to firmware version 1.00
and above.
Copyright E Tektronix, Inc. 1995. 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.

Tek Secure is a registered trademark of Tektronix, Inc.

TekTools, TekScope, and IsolatedChannel are trademarks of Tektronix, Inc.
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.
Service Assurance
If you have not already purchased Service Assurance for this product, you may
do so at any time during the product's warranty period. Service Assurance
provides Repair Protection and Calibration Services to meet your needs.
Repair Protection extends priority repair services beyond the product's
warranty period; you may purchase up to three years of Repair Protection.
Calibration Services provide annual calibration of your product, standards
compliance and required audit documentation, recall assurance, and reminder
notification of scheduled calibration. Coverage begins upon registration; you
may purchase up to five years of Calibration Service.

Service Assurance Advantages
H Priced well below the cost of a single repair or calibration
H Avoid delays for service by eliminating the need for separate purchase
authorizations from your company
H Eliminates unexpected service expenses

For Information and Ordering
For more information or to order Service Assurance, contact your Tektronix
representative and provide the information below. Service Assurance may not
be available in locations outside the United States of America.
Name VISA or Master Card expiration date or
Company purchase order number
Address Repair Protection (1,2 or 3 years)
City, State, Postal code Calibration Service (1,2,3,4 or 5 years)
Country Instrument model and serial number
Phone Instrument purchase date
Table of Contents

General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
In This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi

Getting Started
Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­1
Replacing the Battery Pack . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­5
Using External Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­7
Using the Tilt Stand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­8
Functional Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­9

Operating Basics
Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­1
Understanding the Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . 2­1
Using Scope Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­6
Using Meter Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­7
Compensating the Oscilloscope Probes . . . . . . . . . . . . . . . . . . . 2­8
Taking Floating Measurements . . . . . . . . . . . . . . . . . . . . . . . . . 2­10
Application Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­13
Displaying an Unknown Signal . . . . . . . . . . . . . . . . . . . . . . . . . 2­14
Measuring Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­16
Measuring the Frequency of a Clock Signal . . . . . . . . . . . . . . . 2­18
Measuring Propagation Delay . . . . . . . . . . . . . . . . . . . . . . . . . . 2­20
Triggering on a Missing Data Pulse . . . . . . . . . . . . . . . . . . . . . 2­22
Detecting Narrow Glitches . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­24
Testing a Switching Transistor Drive Circuit . . . . . . . . . . . . . . 2­26
Measuring Instantaneous Power Dissipation
in a Switching Transistor . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­28
Triggering at a Specific Motor RPM . . . . . . . . . . . . . . . . . . . . . 2­30
Using the Oscilloscope and DMM at the Same Time . . . . . . . . 2­32
Monitoring for Power Surges and Dropouts . . . . . . . . . . . . . . . 2­34
Triggering on a Video Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­36
Triggering on a Video Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­38



THS 710 & THS 720 User Manual i
Table of Contents




Reference
Introduction to Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­1
ACQUIRE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­3
AUTORANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­8
CURSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­11
DISPLAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­13
HARD COPY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­17
HOLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­19
HORIZONTAL Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­20
MEAS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­24
METER Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­31
SAVE/RECALL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­37
SCOPE Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­40
TRIGGER Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­46
UTILITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­53
VERTICAL Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­59

Appendices
Appendix A: Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . A­1
Appendix B: Factory Setup . . . . . . . . . . . . . . . . . . . . . . . . . . B­1
Appendix C: Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C­1
Appendix D: Performance Verification . . . . . . . . . . . . . . . . . D­1
Test Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D­2
Performance Verification Procedures . . . . . . . . . . . . . . . . . . . . D­4
Appendix E: General Care and Cleaning . . . . . . . . . . . . . . . E­1
General Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E­1
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E­1

Glossary and Index
Glossary
Index




ii THS 710 & THS 720 User Manual
General Safety Summary
Review the following safety precautions to avoid injury and prevent
damage to this product or any products connected to it.
Only qualified personnel should perform service procedures.

Injury Precautions
Use Proper Power Cord. To avoid fire hazard, use only the power cord
specified for this product.
Avoid Electric Overload. To avoid injury or fire hazard, do not apply
potential to any input, including the common inputs, that varies from
ground by more than the maximum rating for that input.
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.
Do Not Operate Without Covers. To avoid electric shock or fire hazard,
do not operate this product with covers or panels removed.
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.

Product Damage Precautions
Use Proper Power Source. Do not operate this product from a power
source that applies more than the voltage specified.
Do Not Operate With Suspected Failures. If you suspect there is damage
to this product, have it inspected by qualified service personnel.




THS 710 & THS 720 User Manual iii
General Safety Summary




Safety Terms and Symbols
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.
Symbols on the Product. These symbols may appear on the product:




DANGER Protective Ground ATTENTION Double
High Voltage (Earth) Terminal Refer to Manual Insulated




Certifications and Compliances
CSA Certified AC Adapter. CSA Certification includes the AC adapters
appropriate for use in the North America power network. All other
AC adapters supplied are approved for the country of use.
Compliances. Consult the product specifications for Overvoltage
Category and Safety Class.




iv THS 710 & THS 720 User Manual
Preface

This User Manual describes the capabilities, operation, and
applications of the THS 710 and THS 720 TekScope instruments.

In This Manual
The following table shows you where to find information in this
manual.


If you are looking for: Turn to:
Product overview Product Description on page 1­1
Details about a product feature Reference on page 3­1
Look up the front-panel button for the
feature
Application examples Application Examples on page 2­13
Operation instructions Understanding the Front Panel on
page 2­1
Information about battery operation Changing the Battery Pack on
page 1­5
Information about using external Using External Power on page 1­7
power
Information about making a hard copy HARD COPY on page 3­17
Technical specifications Specifications appendix on page A­1
Recommended accessories Accessories appendix on page C­1




THS 710 & THS 720 User Manual v
Preface




Conventions
TekScope instrument setups are shown in tables. The Application
Examples and Performance Verification sections use tables to show
specific setups. The Reference section uses similar tables to show the
complete contents of the menu system.
The header of each table contains icons that represent the controls
and menu items used to set up the instrument. To make a specific
setup, read the table from left to right and then from top to bottom as
shown below. The table contains the symbol "--" if no action is
required.




1. Choose 2. Press this 3. Press this 4. Press the 5. Use the
scope mode button on the bezel button. bezel button +/­ rocker to
or meter front panel. again until set the value
mode. this selection for a parame-
is highlighted. ter.


6. 7. --


8. 9. 10.




vi THS 710 & THS 720 User Manual
Getting Started
Getting Started

In addition to a brief product description, this chapter covers the
following topics:
H How to change the battery pack
H How to use external power
H How to use the tilt stand
H How to perform a quick functional check

Product Description
The THS 710 and THS 720 TekScope instruments combine a
two-channel oscilloscope and a digital multimeter (DMM) in a
rugged, handheld package.

General Features
H Battery power or external power
H High-resolution, high-contrast display with temperature
compensation for clear visibility over a wide temperature range
H Onboard waveform, data, and setup storage
H RS-232 communication port to load setups, download wave-
forms, and make hard copies
H Fully programmable through the RS-232 communication port




THS 710 & THS 720 User Manual 1­1
Getting Started




Oscilloscope Features
The TekScope instrument is a powerful, two-channel oscilloscope
with the following features:
H Autoranging for quick setup and hands-free operation
H 100 MHz (THS 720) or 60 MHz (THS 710) bandwidth with
selectable 20 MHz bandwidth limit
H 500 MS/s (THS 720) or 250 MS/s (THS 710) sample rate and
2,500 point record length
H Separate digitizers for each channel (both channels always
acquire simultaneously)
H Waveform averaging and enveloping with hardware peak
detection
H Digital Real Time digitizing (up to five-times oversampling),
sin(x)/x interpolation, and peak-detect acquisition to limit the
possibility of aliasing
H Independently isolated channels to allow improved safety for
measurements to 1000 VRMS while floating up to 600 VRMS
using P5102 probes
H Cursors and 21 continuously updated, automatic measurements
H Simultaneous oscilloscope and meter operation on the same or
on separate signals
H Advanced pulse and video trigger capability




1­2 THS 710 & THS 720 User Manual
Getting Started




Meter Features
The TekScope instrument is also a full-featured DMM with the
following features:
H True RMS VAC, VDC, W, continuity, and diode-check functions
H Autoranging or manual ranging
H Data logger plot of meter measurements over a period of time
H Max, min, delta max-min, relative-delta, and average statistics in
the readout
H Bar graph for an "analog meter" feel
H Capability to float independently to 600 VRMS
H Overvoltage indicator warns when an overvoltage is applied to
the input




THS 710 & THS 720 User Manual 1­3
Getting Started




Input and Output Connectors
All input and output connectors are located on the top and side
panels as shown below.


NOTE. See the back of the instrument for maximum voltage ratings.




Top panel




Side panel




1­4 THS 710 & THS 720 User Manual
Getting Started




Replacing the Battery Pack
For portable operation, use the rechargeable battery pack.
You can replace the battery pack without losing any saved informa-
tion. The current setup, saved setups, saved waveforms, and saved
data are all stored in nonvolatile memory that does not depend on
battery power.

CAUTION. To prevent loss of saved information, set the ON/STBY
switch to STBY before removing the battery back.




Battery pack




THS 710 & THS 720 User Manual 1­5
Getting Started




Battery Life
From a full charge, you can operate the TekScope instrument
continuously for approximately two hours. You can extend the
battery life by using automatic Power Off Time-out or Backlight
Time-out. Refer to page 3­56 for a description of these features.
The TekScope instrument turns off automatically when the battery
runs low. A low-battery message appears in the display about ten
minutes before the automatic shutdown.
Nickel-cadmium batteries can lose capacity permanently if not
allowed to discharge completely. Whenever possible, allow the
battery to discharge completely before you recharge it to minimize
this capacity loss.

Charging the Battery Pack
Before using the battery for the first time, it must be charged. You
can use external power to charge the battery pack while it is in the
TekScope instrument. Or you can charge the battery pack with the
optional external battery charger. Typical battery charging times are
listed below.


Configuration Typical Charging Time
Battery pack in TekScope instrument 20 hours
Battery pack in external charger 1.5 hours



CAUTION. To avoid loss of saved information when a battery pack is
not installed, set the ON/STBY control to STBY before disconnecting
external power.




1­6 THS 710 & THS 720 User Manual
Getting Started




Using External Power
Using external power from the AC adapter or cigarette lighter
adapter has the following advantages:
H Saves internal battery power for portable operation later
H Charges internal battery pack
H Allows extended operation; the Standby Time-out and Backlight
Time-out features are automatically disabled when external
power is used
H Maintains floating measurement capability of the oscilloscope
channels and DMM
Attach the external power source as shown below.
The DC INPUT disconnects itself if an overvoltage is applied. If this
occurs, disconnect and then reconnect the AC adapter or cigarette
lighter adapter to resume operation from external power.




External power to
DC INPUT




CAUTION. To avoid overheating, do not connect external power while
the instrument is in a confined space, such as in the soft case.




THS 710 & THS 720 User Manual 1­7
Getting Started




Using the Tilt Stand
A built-in tilt stand folds out and snaps back into place when not in
use. For benchtop use, lock the tilt stand in place with the hinged
flap. To hang the TekScope instrument over a nail, rotate the tilt
stand 180°. You can also extend the hinged flap as shown to hang the
instrument from a ladder rung or over the top of a door.




1­8 THS 710 & THS 720 User Manual
Getting Started




Functional Check
After you install batteries or connect external power, you can
perform this quick functional check to verify that your TekScope
instrument is operating correctly.
1. Press the ON/OFF button to turn on the TekScope instrument.
2. After a few seconds, you should see a window with the message
Power-On self check PASSED. Press the CLEAR MENU button.
3. Press the SCOPE button.
4. Connect the oscilloscope probe to the channel 1 input BNC.
Attach the probe tip and reference lead to the PROBE COMP
connectors on the right side of the TekScope instrument.



Ch 1



Probe reference lead to


Probe tip to PROBE COMP




THS 710 & THS 720 User Manual 1­9
Getting Started




5. Press the AUTORANGE button. Within a few seconds, you
should see a square wave in the display (approximately 1.2 kHz).
If you want, repeat steps 4 and 5 for channel 2 of the oscillo-
scope.
6. Press the METER button.
7. Press the VDC bezel button
8. Press the AUTORANGE button.
9. Connect meter leads to the TekScope instrument and touch the
meter lead tips to the PROBE COMP output as shown below.




DMM lead to PROBE COMP



COM lead to




10. Verify that the TekScope instrument measures an average DC
voltage of 2.5 ± 0.25 V.




1­10 THS 710 & THS 720 User Manual
Operating Basics
Functional Overview

This section covers the following topics:
H Understanding the front panel
H Using scope mode
H Using meter mode
H Connecting and using the probes
H Taking floating measurements
You can find specific information about each of the controls in the
Reference chapter of this manual.

Understanding the Front Panel
The front panel has buttons for the functions you use most often and
menus to access more specialized functions. With the autorange
feature, you can setup the TekScope instrument automatically in both
scope and meter modes.

Using the Menu System
To use the menu system, follow the steps shown on the next
two pages.




THS 710 & THS 720 User Manual 2­1
Functional Overview




1. Press a front-panel button to display the menu you want to use.




2. Press a bezel button to choose a menu item. If a pop-up menu
appears, continue to press the bezel button to choose an item in
the pop-up menu. You may need to press the Select Page bezel
button to access additional menu items.




2­2 THS 710 & THS 720 User Manual
Functional Overview




3. Certain menu choices require you to set a numerical parameter to
complete the setup. Use the +/­ rocker to adjust the parameter
value or press the TOGGLE button to reset the parameter to its
default value.




4. If the OK bezel button is displayed, press it to confirm
your choice.




THS 710 & THS 720 User Manual 2­3
Functional Overview




Using the Dedicated Buttons
You can use the dedicated buttons below to take direct actions.
These buttons do not require the use of menus.


1 2 3

4

16

15




14 5



6


13 12 11 10 9 8 7


1. HARD COPY. Initiates a hard copy using the RS-232 port.
2. HOLD. Stops/restarts oscilloscope acquisition or holds/resets
meter readout.
3. AUTORANGE. Selects oscilloscope or meter Autorange
function.




2­4 THS 710 & THS 720 User Manual
Functional Overview




4. CLEAR MENU. Clears menu from display.
5. TRIGGER LEVEL. Adjusts trigger level.
6. SET LEVEL TO 50%. Sets trigger level to midpoint of
oscilloscope waveform.
7. HORIZONTAL POSITION. Adjusts oscilloscope waveform
horizontal position.
8. MAG. Turns 10X horizontal magnification on and off.
9. SEC/DIV. Adjusts horizontal scale factor for oscilloscope or data
logger.
10. VERTICAL POSITION. Adjusts oscilloscope waveform vertical
position.
11. WAVEFORM OFF. Removes selected oscilloscope waveform
from display.
12. VOLTS/DIV. Adjusts oscilloscope vertical scale factor or meter
range.
13. ON/STBY. Selects on or standby. Does not disconnect power
from the instrument.
14. CH 1, CH 2, MATH, REF A, REF B. Displays waveform and
chooses selected waveform.
15. SCOPE. Selects scope mode.
16. METER. Selects meter mode.




THS 710 & THS 720 User Manual 2­5
Functional Overview




Using Scope Mode
Press the front-panel SCOPE button to enter scope mode. Then,
press AUTORANGE to set the vertical, horizontal, and trigger
automatically for a usable display.
The scope-mode display, shown below, is divided into four sections.
Refer to SCOPE Mode on page 3­40 for a description of each
section.


Status line




Graticule Measurement
area readout area




Waveform readout lines




2­6 THS 710 & THS 720 User Manual
Functional Overview




Using Meter Mode
Press the front-panel METER button to enter meter mode. Press one
of the bezel buttons to choose a meter function and then press
AUTORANGE to set the range automatically.
The meter-mode display, shown below, is divided into three sections.
Refer to METER Mode on page 3­31 for a description of each
section and more information about the data logger and bar graph.


Status line




Measurement
readout areas




Graticule area




THS 710 & THS 720 User Manual 2­7
Functional Overview




Compensating the Oscilloscope Probes
To maintain signal fidelity, you must compensate each voltage probe
for the channel input it is connected to.
1. Connect the oscilloscope probe and then press AUTORANGE.



Ch 1



Probe reference lead to


Probe tip to PROBE COMP

AUTORANGE



2. Check the shape of the displayed waveform.



Overcompensated


Undercompensated


Compensated correctly




2­8 THS 710 & THS 720 User Manual
Functional Overview




3. If necessary, adjust the probe for correct compensation.




P6113B P5102


4. Repeat these steps for the other probe and channel.




THS 710 & THS 720 User Manual 2­9
Functional Overview




Taking Floating Measurements
This section covers important issues to consider when taking floating
measurements.

Architecture is Important
For taking floating measurements, the TekScope instrument has
an architectural difference from most other oscilloscopes. The
channel 1, channel 2, and DMM inputs are isolated from the main
chassis and from each other. This architecture allows independent
floating measurements with channel 1, channel 2, and the DMM.



Oscilloscope channels and
DMM float independently.
DC and/or
AC voltage




Electrically insulated case




2­10 THS 710 & THS 720 User Manual
Functional Overview




Many handheld oscilloscope/DMM products have the architecture
shown below, which shares a common reference for the oscilloscope
channels and DMM. With this architecture, all input signals must
have the same voltage reference when you take any multi-channel
measurements.


Oscilloscope channels and
DMM must float together.

DC and/or
AC voltage




Electrically insulated case




Most bench-top oscilloscopes share the above architecture but
without the insulated case. Without differential preamplifiers or
external signal isolators, bench-top oscillscopes are not suitable for
taking floating measurements.




THS 710 & THS 720 User Manual 2­11
Functional Overview




Attach the Reference Leads Correctly
If you are using both of the oscilloscope channels, you must attach
the probe reference lead for each channel directly to your circuit.
These attachments are required because the oscilloscope channels are
electrically isolated; they do not share a common chassis connection.
Use the shortest possible reference lead with each probe to maintain
good signal fidelity. If you are also using the DMM, you must also
attach the DMM common lead to your circuit for the same reason as
above.
The probe reference lead presents a higher capacitive load to the
circuit-under-test than the probe tip. When taking a floating
measurement between two nodes of a circuit, attach the probe
reference lead to the lowest impedance or least dynamic of the two
nodes.

Beware of High Voltages
Understand the voltage ratings for the probes you are using and do
not exceed those ratings. Two ratings are important to know and
understand:
H The maximum measurement voltage from the probe tip to the
probe reference lead
H The maximum floating voltage from the probe reference lead to
earth ground
These two voltage ratings depend on the probe and your application.
Refer to Specifications beginning on page A­1 for more information.


WARNING. To prevent electrical shock, do not exceed the measure-
ment or floating voltage ratings for the oscilloscope input BNC
connector, probe tip, probe reference lead, DMM input connector, or
DMM lead.




2­12 THS 710 & THS 720 User Manual
Application Examples

This section presents a series of application examples. These
simplified examples highlight the features of the TekScope
instrument and give you ideas about using it to solve your own test
problems.
The first two examples demonstrate basic scope and meter operation.
The remaining examples provide an overview of applications that
cover the following areas:
H Digital circuit testing
H Analog circuit testing
H Power electronic testing
H Motor testing
H Power quality monitoring
H Video signal testing




THS 710 & THS 720 User Manual 2­13
Application Examples




Displaying an Unknown Signal
You need to see a signal in a circuit, but you have no previous
knowledge of the signal amplitude, frequency, or shape. Connect the
TekScope instrument to quickly display the signal.




Ch 1




2­14 THS 710 & THS 720 User Manual
Application Examples




Setup to Display an Unknown Signal




SCOPE AUTO -- -- --
RANGE

The autorange feature sets the vertical, horizontal, and trigger
automatically for a usable display. If the signal changes, the setup
tracks those changes.

Going Further
If the autorange setup does not display the waveform exactly the way
you like, you can easily change the setup. Press any of the buttons
below to cancel autorange mode and modify the setup:
H VOLTS/DIV
H SEC/DIV
H TRIGGER LEVEL
H SET TRIGGER LEVEL TO 50%




THS 710 & THS 720 User Manual 2­15
Application Examples




Measuring Resistance
You need to probe a circuit to measure point-to-point resistance.
Connect the TekScope instrument to measure a variety of resistance
values.




29.23 kW




2­16 THS 710 & THS 720 User Manual
Application Examples




Setup to Measure Resistance




METER AUTO W -- --
RANGE

Going Further
If a noisy environment causes an unstable resistance measurement,
use the Average statistic to average the measurements. Refer to
page 3­29 for more information.
You can use the TekScope instrument as a continuity checker. With
the setup below, it beeps when the measured resistance is 50 W or
less (typical).




METER -- -- --
(continuity)

You can also use the TekScope instrument as a semiconductor-junc-
tion checker. Use the setup below to measure the voltage drop across
the junction. The open-circuit voltage is limited to about 4.8 V to
prevent damage to reverse-biased junctions.




METER -- -- --
(diode)




THS 710 & THS 720 User Manual 2­17
Application Examples




Measuring the Frequency of a Clock Signal
You suspect that the frequency of a TTL clock signal is out of
tolerance. Connect the TekScope instrument to the signal to display
it and measure its frequency.




Ch 1




Ch 1
Freq
30.62 MHz




2­18 THS 710 & THS 720 User Manual
Application Examples




Setup to Measure Clock Frequency




SCOPE AUTO -- -- --
RANGE
MEAS Select Frequency
Measmnt for
Ch1
OK Select --
Measrmnt

Going Further
You can add peak-to-peak and duty cycle measurements to the
display with the following additional steps:




SCOPE MEAS Select Page -- --
Select Positive Duty
Measrmnt for Cycle
Ch1
OK Select --
Measrmt
Select Page
(press once)
Select Pk-Pk
Measrmnt for
Ch1
OK Select --
Measrmt




THS 710 & THS 720 User Manual 2­19
Application Examples




Measuring Propagation Delay
You suspect that the memory timing in a microprocessor circuit is
marginal. Set up the TekScope instrument to measure the propaga-
tion delay between the chip-select signal and the data output of the
memory device.




Ch 1 Ch 2




Data CS




D: 12.6 ns




2­20 THS 710 & THS 720 User Manual
Application Examples




Setup to Measure Propagation Delay




SCOPE CH 1 -- -- --
CH 2
AUTO
RANGE1
CURSOR Function V Bars Adjust first
cursor, press
TOGGLE,
and then
adjust second
cursor
1 If necessary, adjust the SEC/DIV rocker to optimize display for
the propagation delay measurement.

Set one cursor to the active edge of the chip-select signal and the
second cursor to the data output transition. Read the propagation
delay in the cursor readout.

Going Further
The above example uses cursors to take relative timing measure-
ments (D-seconds) between two different waveforms. If you are
measuring just one waveform, select the Paired cursor function to
measure D-volts and D-seconds at the same time.




THS 710 & THS 720 User Manual 2­21
Application Examples




Triggering on a Missing Data Pulse
A positive-going TTL data pulse, 20 ms wide, should occur at least
once every millisecond. The circuit is not working correctly and you
suspect an occasional missing pulse. Set up the TekScope instru-
ment to find the missing pulse.




Ch 1




2­22 THS 710 & THS 720 User Manual
Application Examples




Setup to Find Missing Data Pulse




SCOPE AUTO -- -- --
RANGE
TRIGGER Type Pulse
MENU
N
Source Ch1
Polarity and Negative Set width to
Width 1 ms
Trigger When Greater Than --
Width
Mode Normal

The TekScope instrument triggers if the signal remains in the low
state longer than 1 ms. If it does, you have found an occurrence of a
missing pulse.

Going Further
You can extend this application in several ways:
H If the pulses are supposed to be periodic (1 ms period) and you
suspect an occasional extra pulse, change the width setting to
980 ms and the Trigger When submenu to Less Than Width.
With this setup, TekScope instrument triggers if the spacing
between the pulses ever drops below 980 ms, which indicates an
occurrence of an extra pulse.
H Use the second channel to find the cause of the problem. You
can correlate the cause and the effect because the TekScope
instrument always acquires both channels at exactly the
same time.




THS 710 & THS 720 User Manual 2­23
Application Examples




Detecting Narrow Glitches
An elapsed-time counter circuit operates from a precision, 1 kHz
square wave, clock signal supplied by another source. Occasionally,
the counter counts too fast. You suspect glitches in the clock signal
are causing the problem. Set up the TekScope instrument to look for
glitches in the clock signal.




Ch 1




2­24 THS 710 & THS 720 User Manual
Application Examples




Setup to Detect Narrow Glitches




SCOPE AUTO -- -- --
RANGE
ACQUIRE Mode Envelope

Monitor the clock signal for several minutes. In Envelope acquisition
mode, the TekScope instrument displays the 1 kHz square wave
clock signal plus intermittent glitches that are as narrow as 8 ns.

Going Further
You can trigger on the glitch itself with the following setup:




SCOPE TRIGGER Type Pulse --
MENU
N
Source Ch1
Polarity and Positive Set width to
Width 500 ms
Trigger When Less Than --
Width
Mode Normal

A triggers occurs only if a positive pulse narrower than 500 ms (half
the period of the clock signal) is detected.




THS 710 & THS 720 User Manual 2­25
Application Examples




Testing a Switching Transistor Drive Circuit
You need to evaluate the gate-drive circuit for a power FET
(field-effect transistor) in a switching power supply. The gate-drive
timing circuit is referenced to chassis ground. But the gate-drive
signal is transformer-coupled to the FET, which is connected to a
­300 VDC bus. Set up the TekScope instrument to compare the
gate-drive signal at the output of the timing circuit to the signal at
the gate of the FET.




Ch 1 Ch 2
P5102
Probe




Timing
circuit

­300 VDC bus




2­26 THS 710 & THS 720 User Manual
Application Examples




Setup to Test the Transistor Drive Circuit




SCOPE CH 1 -- -- --
CH 2
AUTO
RANGE

You do not have to do anything special to take this difficult
measurement. Because of the isolated channels, you can reference
the channel 1 probe to chassis ground and the channel 2 probe
directly to the ­300 VDC bus. Channel 1 displays the gate-drive
signal directly from the driver and channel 2 displays the signal as it
is received by the power FET.

Going Further
The isolated channels allow you to reference a channel to AC as well
as DC voltages.
H You can connect the P5102 probe reference lead to 50 Hz, 60 Hz,
or 400 Hz AC power lines (up to the maximum voltage rating).
H You can connect the P6113B or P5102 probe reference lead to
dynamic signals with slew rates up to 3000 V/ms (up to the
maximum voltage rating).
Because you can connect to references other than ground, you can
take many measurements that would otherwise require an oscillo-
scope with a differential input.




THS 710 & THS 720 User Manual 2­27
Application Examples




Measuring Instantaneous Power Dissipation
in a Switching Transistor
The output transistor in a switching power supply is hotter than it
should be. You are concerned about its peak power dissipation. Set
up the TekScope instrument to measure the instantaneous power
dissipation of the transistor using an optional current probe.




Ch 1 Ch 2


100 mV/A




Voltage waveform (Ch 1)

Current waveform (Ch 2)


Power waveform (Math)




2­28 THS 710 & THS 720 User Manual
Application Examples




Setup to Measure Instantaneous Power Dissipation




SCOPE CH 1 -- -- --
CH 2 Probe Type Current Set to
Probe 100 mV/A
AUTO -- -- --
RANGE
MATH Function Ch1 × Ch2
CURSOR Function Paired Set cursor

Move the cursor along the power (MATH) waveform and read the
instantaneous power in the cursor readout (for example, @5.63 W).

Going Further
Measure the average power dissipation in the transistor (mean value
of the power waveform) with the following setup:




SCOPE MEAS Select Mean --
Measrmnt for
MATH
OK Select --
Measrmnt

You can also display the I-V characteristic of the transistor for
comparison to its safe operating area using the XY display format.
Refer to page 3­14 for information on XY display format.




THS 710 & THS 720 User Manual 2­29
Application Examples




Triggering at a Specific Motor RPM
You need to measure the start-up current of a 3600-RPM motor at
several specific speeds. A tachometer, attached to the motor,
outputs a low-voltage square wave with 100 pulses per revolution.
Set up the TekScope instrument to trigger at 1200 RPM so you can
measure the current at that speed.
1200 rev min 100 pulses rev
Tachometer output frequency + + 2 kHz
60 s min
1
period 2 kHz
Tachometer pulse width + + + 250 ms
2 2




Ch 1 Ch 2 100 mV/A




Electric motor with
attached tachometer

@: 12.8 A

Tachometer signal (Ch 1)




Motor current (Ch 2)




2­30 THS 710 & THS 720 User Manual
Application Examples




Setup to Trigger at 1200 RPM




SCOPE CH 1 -- -- --
CH 2 Probe Type Current Set to
Probe 100 mV/A
HORIZON- Trigger 50% --
TAL MENU Position
TRIGGER Type Pulse
MENU
N
Source Ch1
Polarity and Positive Set width to
Width 250 ms
Trigger When Equal To Set ±5%
Width
Mode Normal --
CURSOR Function Paired Set cursor to
horizontal
center of
graticule

Set appropriate VOLTS/DIV for each channel. Set SEC/DIV so that
the sweep duration is approximately equal to the motor start-up time.
When the motor starts, the 1200 RPM point is displayed at the center
of the graticule. Use the cursor on channel 2 to measure the armature
current at this point.

Going Further
Change the trigger pulse width setting to trigger at other specific
motor RPMs to complete the test.




THS 710 & THS 720 User Manual 2­31
Application Examples




Using the Oscilloscope and DMM at the Same Time
You need to evaluate a VCO (voltage-controlled oscillator) circuit.
You want to produce a graph of the output frequency as a function of
the input control voltage. Set up the TekScope instrument to provide
you with data for your graph.



Ch 1




Input VCO Output
circuit


3.584 VDC

Ch1
Freq
26.76 MHz




2­32 THS 710 & THS 720 User Manual
Application Examples




Setup to Use DMM and Oscilloscope Together




METER AUTO VDC -- --
RANGE
SCOPE AUTO --
RANGE
MEAS Select Frequency
Measmnt for
CH1
OK Select --
Measrmnt

You can use the DMM to measure the VCO control voltage and the
oscilloscope to measure the output frequency at the same time.
In scope mode, the meter readout is in the upper right corner of the
display. The frequency measurement is at the right side of the
graticule. Both measurements update continuously as you adjust the
VCO control voltage.

Going Further
You may find simultaneous DMM and oscilloscope operation useful
in additional ways:
H To monitor changes in circuit operation as you adjust the power
supply voltage
H To monitor the output amplitude of an optical transmitter or
detector as you adjust its bias voltage




THS 710 & THS 720 User Manual 2­33
Application Examples




Monitoring for Power Surges and Dropouts
You are having intermittent problems with some electronic
equipment that operates unattended at a remote site. You need to
determine if the problem might be caused by momentary power
quality problems in the electrical service to the equipment. Set up the
TekScope instrument to monitor the line voltage for a week and
capture any surges or dropouts that may occur.




Remote site




8 days




2­34 THS 710 & THS 720 User Manual
Application Examples




Setup to Monitor for Power Quality Problems




METER -- VAC -- --
ACQUIRE Mode Peak Detect

You can use the DMM data logger to record measurements over an
extended period of time. Set the full-scale range to 400 V using the
VOLTS/DIV rocker. Adjust the SEC/DIV rocker so that the data
logger horizontal scale is one day per division.
Meter measurements, which occur at a rate of approximately ten per
second, are captured over an eight-day period of time.

Going Further
Use the cursors to determine when a power disturbance occurred (to
within the nearest 24 minutes).




SCOPE CURSOR Function Vertical Set cursor

Move either cursor to the location of the power disturbance. Read the
relative time in the cursor readout (for example, @ 52 h). Calculate
the absolute time and date of the disturbance using the current time
and this measurement.




THS 710 & THS 720 User Manual 2­35
Application Examples




Triggering on a Video Field
The image quality is poor on a video monitor in a closed-circuit
security system that operates at a 15 kHz scan rate. Set up the
TekScope instrument to display and trigger on field 1 of the video
waveform coming into the monitor.




75 W terminator
Ch 1

Incoming video signal




2­36 THS 710 & THS 720 User Manual
Application Examples




Setup to Trigger on Field 1




SCOPE VERTICAL Probe Type Voltage Probe Set to 1X
MENU
AUTO -- -- --
RANGE
DISPLAY Style Dot Set to 100 ms
Accumulate
TRIGGER Type Video --
MENU
N
Trigger On Field 1
Scan Rate -- Set to
15-20 kHz

Adjust the SEC/DIV rocker to 2 ms/div to display field 1 across
about eight divisions. The Dot Accumulate display style simulates an
analog oscilloscope display of the video signal.

Going Further
If you are testing a higher resolution video system, you can trigger
on video signals with scan rates up to 65 kHz.




THS 710 & THS 720 User Manual 2­37
Application Examples




Triggering on a Video Line
Now you want to see one line of the staircase test pattern. Set up the
TekScope instrument to display and trigger on a video line.




75 W terminator
Ch 1

Incoming video signal




2­38 THS 710 & THS 720 User Manual
Application Examples




Setup to Trigger on a Video Line




SCOPE VERTICAL Probe Type Voltage Probe Set to 1X
MENU
AUTO -- -- --
RANGE
ACQUIRE Mode Peak Detect
TRIGGER Type Video
MENU
N
Trigger On Lines

Adjust the SEC/DIV rocker to 10 ms/div to display the lines across
about six divisions.

Going Further
If you need to display a specific video line, use the following
method:
1. Trigger on the video field that contains the line you want to
display (see the Triggering on a Video Field application
example).
2. Display the delayed time base. Set the delay time value to the
time from the start of the field to the start of the line of interest.
Refer to page 3­22 for information about using the delayed time
base.
3. Adjust the delayed time base SEC/DIV to display the video line
of interest.




THS 710 & THS 720 User Manual 2­39
Application Examples




2­40 THS 710 & THS 720 User Manual
Reference
Introduction to Reference
This chapter contains detailed information about the operation of
the THS 710 and THS 720 TekScope instruments. The topics in
this chapter are arranged alphabetically by button name.


Reference Topic Page
Acquire 3­3
Autorange 3­8
Cursor 3­11
Display 3­13
Hard copy 3­17
Hold 3­19
Horizontal controls 3­20
Measure 3­24
Meter mode 3­31
Save/Recall 3­37
Scope mode 3­40
Trigger controls 3­46
Utility 3­53
Vertical controls 3­59




THS 710 & THS 720 User Manual 3­1
Introduction to Reference




3­2 THS 710 & THS 720 User Manual
ACQUIRE




ACQUIRE
Press the ACQUIRE button to set acquisition parameters indepen-
dently for scope mode and meter mode.

Acquire Menu in Scope Mode




SCOPE ACQUIRE Mode Sample
Peak Detect
Envelope
Average
Stop After HOLD Button Only
Single Acquisition
Sequence
Force Trigger --

Key Points
Acquisition Modes. You can choose one of four acquisition modes:
Sample, Peak Detect, Envelope, or Average. The next two pages
describe these acquisition modes in detail.




THS 710 & THS 720 User Manual 3­3
ACQUIRE




Samples acquired in four Acquisition Displayed record
acquisition intervals mode points
Interval 1 2 3 4 Interval 1 2