GW Instek GDS-1000A-U User Manual

Digital Storage Oscilloscope

GDS-1000A-U Series

USER MANUAL

GW INSTEK PART NO. 82DS-112AUEC1

ISO-9001 CERTIFIED MANUFACTURER

May 2014 edition

This manual contains proprietary information, which is protected by
copyright. All rights are reserved. No part of this manual may be
photocopied, reproduced or translated to another language without
prior written consent of Good Will Corporation.

The information in this manual was correct at the time of printing.
However, Good Will continues to improve its products and therefore
reserves the right to change the specifications, equipment, and
maintenance procedures at any time without notice.

Good Will Instrument Co., Ltd.
No. 7-1, Jhongsing Rd., Tucheng Dist., New Taipei City 236, Taiwan.

TABLE OF CONTENTS

Table of Contents

SAFETY INSTRUCTIONS .................................. 8

Safety Symbols ....................................................................... 8

Safety Guidelines .................................................................... 9

Power cord for the United Kingdom .................................... 12

GETTING STARTED ........................................ 13

Main Features ................................................................... 13

Panel Overview .................................................................. 15

Front Panel ........................................................................... 15

Rear Panel ............................................................................. 19

Display .................................................................................. 20

Setting up the Oscilloscope ............................................... 21

QUICK REFERENCE ....................................... 24

Menu Tree and Shortcuts................................................... 24

CH1/CH2 key ....................................................................... 25

Cursor key 1/2 ...................................................................... 26

Cursor key 2/2 ...................................................................... 26

Display key ............................................................................ 27

Autoset key ........................................................................... 27

Hardcopy key ........................................................................ 27

Help key ................................................................................ 28

Horizontal menu key ............................................................ 28

Math key 1/2 (+/-/x) ............................................................. 29

Math key 2/2 (FFT/FFT rms) ............................................... 30

Measure key.......................................................................... 31

Run/Stop key ........................................................................ 31

Save/Recall key 1/10 ............................................................ 32

Save/Recall key 2/10 ............................................................ 32

Save/Recall key 3/10 ............................................................ 33

Save/Recall key 4/10 ............................................................ 33

Save/Recall key 5/10 ............................................................ 34

Save/Recall key 6/10 ............................................................ 34

Save/Recall key 7/10 ............................................................ 35

Save/Recall key 8/10 ............................................................ 35

Save/Recall key 9/10 ............................................................ 36

Save/Recall key 10/10 .......................................................... 36

Trigger key 1/6 ...................................................................... 37

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GDS-1000A-U Series User Manual

Trigger key 2/6 ..................................................................... 37

Trigger key 3/6 ..................................................................... 38

Trigger key 4/6 ..................................................................... 38

Trigger key 5/6 ..................................................................... 39

Trigger key 6/6 ..................................................................... 39

Utility key 1/11 (Utility #1) .................................................. 40

Utility 2/11 (Utility #2) ........................................................ 40

Utility key 3/11 (Utility #3) .................................................. 41

Utility key 4/11 (Hardcopy -Save All) ................................... 41

Utility key 5/11 (Hardcopy -Printer) .................................... 42

Utility key 6/11 (Hardcopy -Save Image) ............................. 42

Utility key 7/11 (Probe compensation) ............................... 43

Utility key 8/11 (Go-NoGo) ................................................. 43

Utility key 9/11 (Data Logging 1/2) ..................................... 44

Utility key 10/11 (Data Logging 2/2) ................................... 44

Utility key 11/11 (Self CAL Menu) ....................................... 44

Default Settings ................................................................. 45

Built-in Help ...................................................................... 46

MEASUREMENT ............................................ 47

Basic Measurements ......................................................... 47

Activating a channel ............................................................. 47

Using Autoset ...................................................................... 48

Running and stopping the trigger ....................................... 50

Changing the horizontal position and scale........................ 51

Changing the vertical position and scale ............................ 52

Using the probe compensation signal ................................ 53

Automatic Measurements .................................................. 55

Measurement items ............................................................. 55

Automatic measurement gating .......................................... 57

Automatically measuring the input signals ......................... 58

Cursor Measurements ....................................................... 61

Using the horizontal cursors ............................................... 61

Using the vertical cursors .................................................... 62

Math Operations ............................................................... 63

Overview ............................................................................... 63

Adding, subtracting or multiplying signals ......................... 64

Using the FFT function ........................................................ 65

Go No-Go Testing .............................................................. 67

Overview ............................................................................... 67

Edit: NoGo When ................................................................. 68

Edit: Source .......................................................................... 68

Edit: NoGo Violation Conditions ......................................... 69

4

TABLE OF CONTENTS

Edit: Template (boundary) ................................................... 69

Run Go-NoGo Tests ............................................................. 73

Data Logging ..................................................................... 74

Overview ............................................................................... 74

Edit: Source .......................................................................... 75

Edit: Setup Parameters ........................................................ 75

Run Data logging ................................................................. 77

CONFIGURATION .......................................... 78

Acquisition ........................................................................ 78

Selecting the acquisition mode ............................................ 78

Selecting Delay mode ........................................................... 80

Real time vs Equivalent time sampling mode ..................... 82

Display .............................................................................. 83

Selecting vector or dot drawing ........................................... 83

Accumulating the waveform ................................................ 83

Adjusting the display contrast ............................................. 84

Selecting the display grid ..................................................... 84

Horizontal View ................................................................. 85

Moving the waveform position horizontally ........................ 85

Selecting the horizontal scale .............................................. 85

Selecting the waveform update mode ................................. 86

Zooming the waveform horizontally .................................... 87

Viewing waveforms in the X-Y mode ................................... 88

Horizontal Adjustment Menu .............................................. 89

Vertical View (Channel) ..................................................... 91

Moving the waveform position vertically ............................. 91

Selecting the vertical scale ................................................... 91

Selecting the coupling mode ............................................... 91

Expand Vertical Scale Center / Ground ............................... 92

Inverting the waveform vertically ......................................... 93

Limiting the waveform bandwidth ....................................... 94

Probe attenuation level and type ......................................... 94

Trigger ............................................................................... 96

Trigger type ........................................................................... 96

Trigger parameter ................................................................. 96

Configuring Holdoff ............................................................. 98

Configuring the edge trigger ................................................ 99

Configuring the video trigger ............................................. 100

Configuring the pulse width trigger ................................... 101

Manually triggering the signal ........................................... 103

Rear Panel USB Port Interface ......................................... 104

Remote Control Interface ................................................ 105

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GDS-1000A-U Series User Manual

System Settings ............................................................... 107

Viewing the system information ........................................ 107

Selecting the language ....................................................... 107

SAVE/RECALL .............................................. 109

File Structures ................................................................. 109

Display image file format ................................................... 109

Waveform file format ......................................................... 109

Setup file format ................................................................ 112

Using the USB file utilities ................................................. 113

Quick Save (HardCopy) ................................................... 115

Save ................................................................................ 117

File type/source/destination.............................................. 117

Saving the panel settings ................................................... 118

Saving the waveform .......................................................... 119

Saving the display image ................................................... 121

Saving all (panel settings, display image, waveform) ....... 122

Recall .............................................................................. 124

File type/source/destination.............................................. 124

Recalling the default panel settings ................................... 125

Recalling a reference waveform to the display .................. 126

Recalling panel settings ..................................................... 126

Recalling a waveform ......................................................... 127

Recall Image ....................................................................... 129

MAINTENANCE ........................................... 131

Vertical Resolution Calibration ........................................ 131

Probe Compensation ....................................................... 132

FAQ .............................................................. 134

The input signal does not appear in the display. .............. 134

I want to remove some contents from the display. .......... 134

The waveform does not update (frozen). .......................... 135

The probe waveform is distorted. ...................................... 135

Autoset does not catch the signal well. ............................. 135

I want to clean up the cluttered panel settings. ................ 135

The saved display image is too dark on the background. . 135

The accuracy does not match the specifications. ............. 136

The oscilloscope will not allow a 2M waveform to be saved.

............................................................................................ 136

6

TABLE OF CONTENTS

APPENDIX .................................................... 137

Fuse Replacement ........................................................... 137

GDS-1000A-U Series Specifications ................................. 138

Model-specific specifications ............................................. 138

Common specifications ..................................................... 139

Probe Specifications ........................................................ 141

GDS-1072A-U Probe ........................................................... 141

GDS-1102A-U Probe ........................................................... 141

GDS-1152A-U Probe ........................................................... 142

Dimensions ..................................................................... 143

EC Declaration of Conformity .......................................... 144

INDEX .......................................................... 145

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GDS-1000A-U Series User Manual

WARNING

Warning: Identifies conditions or practices that
could result in injury or loss of life.

CAUTION

Caution: Identifies conditions or practices that
could result in damage to the oscilloscope or to
other objects or property.

DANGER High Voltage

Attention: Refer to the Manual

Protective Conductor Terminal

Earth (Ground) Terminal

SAFETY INSTRUCTIONS

This chapter contains important safety instructions
that should be followed when operating and
storing the oscilloscope. Read the following before
any operation to ensure your safety and to keep
the oscilloscope in the best condition.

Safety Symbols

These safety symbols may appear in this manual or on the
oscilloscope.

8

SAFETY INSTRUCTIONS

Do not dispose electronic equipment as unsorted
municipal waste. Please use a separate collection
facility or contact the supplier from which this
instrument was purchased.

General
Guideline

CAUTION

 Make sure the BNC input voltage does not

exceed 300V peak.

 Never connect a hazardous live voltage to the

ground side of the BNC connectors. It might
lead to fire and electric shock.

 Do not place heavy objects on the oscilloscope.
 Avoid severe impact or rough handling that

may damage the oscilloscope.

 Avoid discharges of static electricity on or near

the oscilloscope.

 Use only mating connectors, not bare wires, for

the terminals.

 Do not block the cooling fan vent.
 Do not perform measurements at power sources

and building installation sites (Note below).

 The oscilloscope should only be disassembled

by a qualified technician.

(Measurement categories) EN 61010-1:2001 specifies the
measurement categories and their requirements as follows. The
GDS-1000A-U falls under category II.

 Measurement category IV is for measurement performed at the

source of a low-voltage installation.

 Measurement category III is for measurement performed in a

building installation.

 Measurement category II is for measurement performed on

circuits directly connected to a low voltage installation.

 Measurement category I is for measurements performed on

circuits not directly connected to Mains.

Safety Guidelines

9

GDS-1000A-U Series User Manual

Power Supply

WARNING

 AC Input voltage: 100 ~ 240V AC, 47 ~ 63Hz
 The power supply voltage should not fluctuate

more than 10%.

 Connect the protective grounding conductor of

the AC power cord to an earth ground.

Fuse

WARNING

 Fuse type: T1A/250V
 To ensure fire protection, replace the fuse only

with the specified type and rating.

 Disconnect the power cord before replacing the

fuse.

 Make sure the cause of fuse blowout is fixed

before replacing the fuse.

Cleaning the
oscilloscope

 Disconnect the power cord before cleaning the

oscilloscope.

 Use a soft cloth dampened in a solution of mild

detergent and water. Do not spray any liquid
into the oscilloscope.

 Do not use chemicals containing harsh products

such as benzene, toluene, xylene, and acetone.

Operation
Environment

 Location: Indoor, no direct sunlight, dust free,

almost non-conductive pollution (Note below)

 Relative Humidity: ≤ 80%, 40°C or below

≤ 45%, 41°C~50°C

 Altitude: < 2000m
 Temperature: 0°C to 50°C

10

SAFETY INSTRUCTIONS

(Pollution Degree) EN 61010-1:2001 specifies pollution degrees and
their requirements as follows. The oscilloscope falls under degree 2.

Pollution refers to “addition of foreign matter, solid, liquid, or

gaseous (ionized gases), that may produce a reduction of dielectric
strength or surface resistivity”.

 Pollution degree 1: No pollution or only dry, non-conductive

pollution occurs. The pollution has no influence.

 Pollution degree 2: Normally only non-conductive pollution

occurs. Occasionally, however, a temporary conductivity caused
by condensation must be expected.

 Pollution degree 3: Conductive pollution occurs, or dry, non-

conductive pollution occurs which becomes conductive due to
condensation which is expected. In such conditions, equipment
is normally protected against exposure to direct sunlight,
precipitation, and full wind pressure, but neither temperature
nor humidity is controlled.

Storage
environment

 Location: Indoor
 Storage Temperature: -10°C~60°C, no

condensation-

 Relative Humidity: 93% @ 40°C

65% @ 41°C ~60°C

Disposal

Do not dispose this instrument as unsorted
municipal waste. Please use a separate collection
facility or contact the supplier from which this
instrument was purchased. Please make sure
discarded electrical waste is properly recycled to
reduce environmental impact.

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GDS-1000A-U Series User Manual

Green/ Yellow:

Earth

Blue:

Neutral

Brown:

Live (Phase)

Power cord for the United Kingdom

When using the oscilloscope in the United Kingdom, make sure the
power cord meets the following safety instructions.

NOTE: This lead/appliance must only be wired by competent persons

WARNING: THIS APPLIANCE MUST BE EARTHED
IMPORTANT: The wires in this lead are coloured in accordance with the
following code:

As the colours of the wires in main leads may not correspond with the
coloured marking identified in your plug/appliance, proceed as follows:

The wire which is coloured Green & Yellow must be connected to the Earth
terminal marked with either the letter E, the earth symbol or coloured

Green/Green & Yellow.

The wire which is coloured Blue must be connected to the terminal which is
marked with the letter N or coloured Blue or Black.

The wire which is coloured Brown must be connected to the terminal
marked with the letter L or P or coloured Brown or Red.

If in doubt, consult the instructions provided with the equipment or contact
the supplier.

This cable/appliance should be protected by a suitably rated and approved
HBC mains fuse: refer to the rating information on the equipment and/or
user instructions for details. As a guide, a cable of 0.75mm2 should be
protected by a 3A or 5A fuse. Larger conductors would normally require
13A types, depending on the connection method used.

Any exposed wiring from a cable, plug or connection that is engaged in a
live socket is extremely hazardous. If a cable or plug is deemed hazardous,
turn off the mains power and remove the cable, any fuses and fuse
assemblies. All hazardous wiring must be immediately destroyed and
replaced in accordance to the above standard.

12

GETTING STARTED

Model name

Frequency bandwidth

Input channels

GDS-1072A-U

DC – 70MHz (–3dB)

2

GDS-1102A-U

DC – 100MHz (–3dB)

2

GDS-1152A-U

DC – 150MHz (–3dB)

2

Performance

 1 GS/s real-time sampling rate
 25GS/s equivalent-time sampling rate
 2M points record length
 Up to 10ns peak detection
 2mV~10V vertical scale
 1ns ~ 50s time scale

Features

 5.7 inch color TFT display
 Saving and recalling setups and waveforms
 27 automatic measurements
 Multi-language menu (12 languages)
 Math operation: Addition, Subtraction,

multiplication, FFT, FFT RMS

 Data logging
 Go-NoGo testing
 Edge, video, pulse width trigger

GETTING STARTED

The Getting started chapter introduces the
oscilloscope’s main features, appearance, and set
up procedure.

Main Features

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GDS-1000A-U Series User Manual

 Compact size: (W) 310 x (D) 140 x (H) 142 mm
 Probe factor from 0.1X~2000X voltage/current

Interface

 USB 2.0 full-speed interface for saving and

recalling data

 Calibration output
 External trigger input
 USB slave interface for remote control

14

GETTING STARTED

LCD
Display

Function
keys

VARIABLE
knob

Menu keys

Trigger
LEVEL knob

Trigger
keys

Ground
Terminal

CH1
terminal

USB port CH2

terminal

Probe
compensation
output

EXT TRIG
terminal

Power
switch

Horizontal
POSITION
knob

Horizontal
MENU key

TIME/DIV
knob

CH1/CH2/
MATH keys

Vertical
POSITION
knob

VOLTS/DIV
knob

VOLTS/DIV VOLTS/DIV TIME/DIV

CH 1 MATH CH 2 MENU MENU

Acquire

Display

Utility Help

Run/Stop

VARIABLE

FORCE

Autoset

Cursor

SINGLE

Hardcopy

Measure

Save/Recall

LEVEL

VERTICAL HORIZONTAL TRIGGER

CH1

CAT300V

MW15pF

MAX. 300Vpk

1

CH2 EXT TRIG

CAT300V

MW15pF

MAX. 300Vpk

1

X Y

150 MHz 1 G Sa/s

Digital Storage Oscilloscope

GDS-1152A-U

LCD display

TFT color, 320 x 234 resolution, wide angle view
LCD display.

Function keys:
F1 (top) to
F5 (bottom)

Activates the functions which
appear in the left side of the LCD
display.

Variable knob

VARIABLE

Increases or decreases values and
moves to the next or previous
parameter.

Acquire key

Acquire

Configures the acquisition mode
(page 78).

Display key

Display

Configures the display settings
(page 83).

Cursor key

Cursor

Runs cursor measurements (page

61).

Panel Overview

Front Panel

(Continued on next page)

15

GDS-1000A-U Series User Manual

Utility key

Utility

Configures the Hardcopy function
(page 115), shows the system
status (page 107), selects the menu
language (page 107), runs the self
calibration (page 131), configures
the probe compensation signal
(page 132), and selects the USB
host type(page 104).

Help key

Help

Shows the Help contents on the
display (page 46).

Autoset key

Autoset

Automatically configures the
horizontal, vertical, and trigger
settings according to the input
signal (page 48).

Measure key

Measure

Configures and runs automatic
measurements (page 55).

Save/Recall key

Save/Recall

Saves and recalls images,
waveforms, or panel settings
(page 109).

Hardcopy key

Hardcopy

Stores images, waveforms, or
panel settings to USB (page 115).

Run/Stop key

Run/Stop

Runs or stops triggering (page 50).

Trigger level knob

LEVEL

TRIGGER

Sets the trigger level (page 96).

Trigger menu key

MENU

Configures the trigger settings
(page 96).

Single trigger key

SINGLE

Selects the single triggering mode
(page 103).

Trigger force key

FORCE

Acquires the input signal once
regardless of the trigger condition
at the time (page 103).

16

GETTING STARTED

Horizontal menu
key

MENU

Configures the horizontal view
(page 85).

Horizontal
position knob

Moves the waveform horizontally
(page 85).

TIME/DIV knob

TIME/DIV

Selects the horizontal scale (page

85).

Vertical position
knob

Moves the waveform vertically
(page 91).

CH1/CH2 key

CH 1

Configures the vertical scale and
coupling mode for each channel
(page 91).

VOLTS/DIV knob

VOLTS/DIV

Selects the vertical scale (page 91).

Input terminal

CH1

Accepts input signals: 1MΩ±2%
input impedance, BNC terminal.

Ground terminal

Accepts the DUT ground lead to
achieve a common ground.

MATH key

MATH

Performs math operations (page

63).

USB port

Facilitates transferring waveform
data, display images, and panel
settings (page 109).

Probe
compensation
output

Outputs a 2Vp-p, square signal for
compensating the probe (page

132) or demonstration.

External trigger
input

EXT TRIG

Accepts an external trigger signal
(page 96).

17

GDS-1000A-U Series User Manual

Power switch

Powers the oscilloscope on or off.

18

Rear Panel

LINE VOLTAGE

AC 100 240V

FUSE RATING

RANGE

T1A 250V

FREQUENCY 50 60Hz

POWER MAX. 18W 40VA

USB portCAL outputPower cord socketFuse socket

Security lock
slot

Power cord
socket

Fuse socket

Power cord socket accepts the AC
mains, 100 ~ 240V, 50/60Hz.

The fuse socket holds the AC main
fuse, T1A/250V.

For the fuse replacement
procedure, see page 137.

USB slave port

Accepts a type B (slave) male USB
connector for remote control of the
oscilloscope (page 104).

Calibration
output

Outputs the calibration signal used
in vertical scale accuracy calibration
(page 131).

Security lock slot

Standard laptop security lock slot
for ensuring the security of the
GDS-1000A-U.

GETTING STARTED

19

Display

Waveform marker

Vertical status Horizontal status Frequency Trigger condition

Waveform position Trigger status Acquisition

Menu

Waveforms

Channel 1: Yellow

Channel 2: Blue

Trigger status

Trig’d

A signal is being triggered

Trig?

Waiting for a trigger condition

Auto

Updating the input signal
regardless of trigger conditions

STOP

Triggering is stopped

For trigger setting details, see page 96.

Input signal
frequency

Updates the input signal frequency (the trigger
source signal) in real-time.

“< 2Hz” Indicates that the signal frequency is less
than the lower frequency limit (2Hz) and thus not
accurate.

Trigger
configuration

Shows the trigger source, type, and slope. In case
of the Video trigger, shows the trigger source and
polarity.

Horizontal status

Vertical status

Shows the channel configurations: coupling mode,
vertical scale, and horizontal scale.

GDS-1000A-U Series User Manual

20

GETTING STARTED

Background

This section describes how to set up the
oscilloscope properly including adjusting the
handle, connecting a signal, adjusting the scale,
and compensating the probe. Before operating the
oscilloscope in a new environment, run these steps
to make sure the oscilloscope is functionally stable.

Procedure

1. Pull both bases of

the handle out
slightly.

2. Turn to one of the three

preset positions.

3. Connect the power cord.

4. Press the power switch. The

display will become active
in approximately 10
seconds.

5. Reset the system by recalling

the factory settings. Press
the Save/Recall key, then
Default Setup. For details
regarding the factory
settings, see page 45.

Default

Setup

Save/Recall

Setting up the Oscilloscope

21

GDS-1000A-U Series User Manual

6. Connect the probe between the Channel1 input

terminal and probe compensation signal output
(2Vp-p, 1kHz square wave).

7. Set the probe attenuation voltage to x10.

VOLTS/DIV VOLTS/DIV TIME/DIV

CH 1 MATH CH 2 MENU MENU

Acquire

Display

Utility Help

Run/Stop

VARIABLE

FORCE

Autoset

Cursor

SINGLE

Hardcopy

Measure

Save/Recall

LEVEL

VERTICAL HORIZONTAL TRIGGER

CH1

CAT300V

MW15pF

MAX. 300Vpk

1

CH2 EXT TRIG

CAT300V

MW15pF

MAX. 300Vpk

1

X Y

X
10

X
1

CH1

x1

x10

8. Press the Autoset key. A

square waveform will
appear in the center of the
display. For details on
Autoset, see page 48.

Autoset

9. Press the Display key, then

Type and select the vector
waveform type.

Type

Vectors

Display

10. Turn the adjustment point on the probe to

flatten the square waveform edge.

22

GETTING STARTED

Over

Compensation

Normal

Under

Compensation

11. Setting up the oscilloscope is complete. You

may continue with the other operations.

Measurement: page 47

Configuration: page 78

23

GDS-1000A-U Series User Manual

Conventions

Examples

Normal

= Press the functional key for “Normal”

Average

= Repeatedly press the functional key for
“Average”

Normal ~ Average

= Select a menu from “Normal” to “Average” and

press its functionality key

Normal→VAR

= Press the functionality key for “Normal”, and

then use the Variable knob

QUICK REFERENCE

This chapter lists the oscilloscope menu tree,
operation shortcuts, built-in help coverage, and
default factory settings. Use this chapter as a
handy reference to access the oscilloscope
functions.

Menu Tree and Shortcuts

24

Normal

Peak

Detect

2/ 4/ 8/ 16/ 32/
64/ 128/ 256

Average

Sample Rate

500MS/s

Acquire

Delay

On

On/ Off

Select acquisition mode

Normal ~ Peak-Detect

Select average number

Average

Turn Delay on/off

Delay On

On/ Off

On/ Off

/ /

Coupling

Invert

Off

BW Limit

Off

Voltage

x1

CH 1

Expand

Center

Voltage/Current

Center/Ground

Turn channel on/off

CH 1/2

Select coupling mode

Coupling

Invert waveform

Invert

Turn bandwidth limit on/off

BW Limit

Select probe type

Voltage↔Current

Select probe attenuation

VAR (0.1x~2000x) (1-2-5 step)

Expand type

Expand

CH1/CH2 key

QUICK REFERENCE

25

Cursor key 1/2

CH1/ 2/ MATH

Source

CH1

X↔ Y

Cursor

X1X2

10.00uS

100.0kHz

0.000uV

X1

-5.000uS

0.000uV

X2

5.000uS

0.000uV

∆ :
f :

Turn cursor on/off

Cursor

Move X1 cursor

X1→ VAR

Move X2 cursor

X2→ VAR

Move both X1 and X2 cursor

X1X2→ VAR

Switch to Y cursor

X↔Y

CH1/ 2/ MATH

Source

CH1

X↔ Y

Cursor

Y1

123.4mV
Y2

12.9mV
Y1Y2

10.5mV

Turn cursor on/off

Cursor

Move Y1 cursor

Y1→ VAR

Move Y2 cursor

Y2→ VAR

Move both Y1 and Y2 cursor

Y1Y2→ VAR

Switch to X cursor

X↔Y

Cursor key 2/2

GDS-1000A-U Series User Manual

26

Display key

Vectors/ Dots

Type

Vectors

On/ Off

Accumulate

Off

Refresh

Contrast

Full

/ /

Display

Select waveform type

Type

Waveform accumulate On/Off

Accumulate

Refresh accumulation

Refresh

Set display contrast

Contrast→VAR

Select display grid

Undo

Type

Fit Screen

Fit Screen
AC Priority

Autoset

Automatically find the signal and set
the scale

Autoset

Change the Type of Autoset mode.

Type (available for a few seconds)

Undo Autoset

Undo (available for a few seconds)

Hardcopy

→ See Utility key (page 40)

Autoset key

QUICK REFERENCE

Hardcopy key

27

GDS-1000A-U Series User Manual

Help

Turn help mode on/off

Help

MENU

Main

Window
Window

Zoom

XY

Roll

MENU

H Pos Adj

Fine

Reset

Hor Pos

Previous

180.0uS
Next

340.0uS

Set/Clear

180.0uS

Fine/Coarse

Switch from Horizontal Menu
to Horizontal Position Menu.

Horizontal MENU

Select main (default) display

Main

Select window mode

Window→TIME/DIV

Zoom in window mode

Window Zoom

Select window roll mode

Roll

Select XY mode

XY

Toggle adjustment mode

H Pos Adj

Reset horizontal marker

Reset

Set Horizontal marker/delete
horizontal marker.

HOR →Set/Clear

Navigate to previous
horizontal marker.

Previous

Navigate to next horizontal
marker.

Next

Help key

Horizontal menu key

28

QUICK REFERENCE

Operation

CH1+CH2

Position

0.00 Div
Unit/Div

2V

-12div ~ +12div

CH1+CH2
CH1-CH2
CH1xCH2
FFT
FFT rms

MATH

200mV~10V/div

Math on/off

Math

Select math operation type (+/–
/x/FFT/FFT rms)

Operation

Set result position

Position→VAR

Math result Volt/Div

Unit/Div→VOLTS/DIV(CH2)

Math key 1/2 (+/-/x)

29

GDS-1000A-U Series User Manual

Operation

FFT

Source

CH1

Zoom

1X

0.0000Hz

1/2/5/10/20X

Window

Hanning

Flattop/
Rectangular/
Blackman/
Hanning

CH1/2

MATH

-12div ~ +12div
20/10/5/2/1 dB

CH1+CH2
CH1-CH2
CH1xCH2
FFT
FFT rms

Vertical

2V

0.00 Div

Math on/off

Math

Select math operation type (+/–
/x/FFT/FFT rms)

Operation

Select FFT source channel

Source

Select FFT window

Window

Select FFT result position

Vertical→VAR

Select vertical scale

Vertical→VOLTS/DIV

Select vertical units

Vertical

Select Zoom level

Zoom(X)→VAR

Select Horizontal position

Zoom(Hz)→VAR

Math key 2/2 (FFT/FFT rms)

30

Measure key

Voltage

Vpp

Previous

Menu

View all/Select
Measurements
(Voltage/
Time/Delay)

Vpp

1:204mV
2: 300mV

Vavg

1: 1.93mV
2: 28.0mV

Frequency

1: 1.000kHz
2: 3.003kHz

Duty Cycle

1: 50.01%
2: 49.88%

Rise Time

1. 76.20us

2. 70.11us

Measure Measure

Source 2

CH2

Source 1

CH1

Turn on/off measurement

Measure

Select measurement type

Voltage/Time/Delay

Select measurement item

VAR or Icon(F3) / → VAR

Go back to previous menu

Previous Menu

Run/Stop

Freeze/unfreeze waveform or trigger

Run/Stop

QUICK REFERENCE

Run/Stop key

31

GDS-1000A-U Series User Manual

Recall

Setup

Recall

Waveform

Display

Refs.

Save

Setup

Save

Waveform

Save

Image

Save

All

To Recall
Setup

To Recall
Waveform

To Save
Setup

To Save
Waveform

To Save
Image

To Save
All

Default

Setup

Save/Recall Save/Recall

To Display
Refs

Recall
Image

To Recall
Image

CSV Format

Fast

Fast/ Detail

Switch to Save or Recall menu

Save/Recall

Recall default setup

Default Setup

Change CSV format

CSV Format

Recall
Setup

Recall

File

Utilities

(USB only)
To File Utilities

Recall Setup

Source

Memory

Memory/USB

Select other menu

Recall Setup

Select setup source

Source →VAR

Recall setup

Recall

Go to USB file utilities

File Utilities

Save/Recall key 1/10

Save/Recall key 2/10

32

QUICK REFERENCE

Recall

Waveform

Recall

File

Utilities

Recall Waveform

Destination

Source

Memory

Memory/USB

(USB only)
To File Utilities

RefA/B

Select other menu

Recall Waveform

Select waveform source

Source →VAR

Select waveform destination

Destination→VAR

Recall waveform

Recall

Go to USB file utilities

File Utilities

Recall
Image

Ref Image

Off

Recall

File

Utilities

(USB only)
To File Utilities

Recall Image

Source

USB

On/Off

Select other menu

Recall Image

Turn reference image on/off

Ref image

Recall waveform

Recall

Go to USB file utilities

File Utilities

Save/Recall key 3/10

Save/Recall key 4/10

33

GDS-1000A-U Series User Manual

Display

Refs.

Ref.A Off

Ref.B Off

On/ Off

On/ Off

Display Refs.

Ref.A On

1V

2.5ms

Select other menu

Display Refs.

Turn ref. waveform A on/off

Ref.A

Turn ref. waveform B on/off

Ref.B

Save

Setup

Destination

Memory

Save

File

Utilities

(USB only)
To File Utilities

Save Setup

Memory/USB

Select other menu

Save Setup

Select destination

Destination →VAR

Save setup

Save

Go to USB file utilities

File Utilities

Save/Recall key 5/10

Save/Recall key 6/10

34

QUICK REFERENCE

Save

Waveform

Source

Save

File

Utilities

Save Waveform

Destination

Memory

Memory
USB Normal
USB 1M
USB 2M/Refs.

(USB only)
To File Utilities

CH1/2/Math
Ref A/B

Select other menu

Save Waveform

Select source

Source →VAR

Select destination

Destination →VAR

Save waveform

Save

Go to USB file utilities

File Utilities

Save

Image

Destination

USB

Save

File

Utilities

(USB only)
To File Utilities

Save Image

Ink Saver

Off

On/ Off

Select other menu

Save Image

Turn on/off ink saver

Ink Saver

Save image

Save

Go to USB file utilities

File Utilities

Save/Recall key 7/10

Save/Recall key 8/10

35

GDS-1000A-U Series User Manual

Save

All

Save

File

Utilities

Save All

Destination

USB

(USB only)
To File Utilities

Ink Saver

Off

On/ Off

USB Normal
USB 1M/ USB 2M

Select other menu

Save All

Turn on/off ink saver

Ink Saver

Select destination

Destination →VAR

Save all

Save

Go to USB file utilities

File Utilities

Select

Delete

Previous

Menu

File Utilities

Rename

New

Folder

Enter

Character

Save

Previous

Menu

Back

Space

Select file/folder

VAR →Select

Create or rename folder/file

New Folder/Rename

VAR →Enter character / Backspace
/ Save / Previous menu

Delete folder/file

Delete

Go to previous menu

Previous menu

Save/Recall key 9/10

Save/Recall key 10/10

36

Trigger key 1/6

Type

Edge

Source

CH1

Mode

Auto

Slope /

Coupling

Holdoff

40.0ns
Set to

Minimum

MENU MENU

Trigger Type

Trigger Holdoff

Select Trigger type or Trigger
Holdoff menu

Type

Type

Video

Source

CH1

Standard

NTSC

NTSC/SECAM/PAL

Line

CH1/2

/

Field 1/ Field 2/ Line

Polarity

Video Trigger

Select video trigger type

Type

Select trigger source

Source

Select video standard

Standard

Select video polarity

Polarity

Select video field/line

Line →VAR

Trigger key 2/6

QUICK REFERENCE

37

Trigger key 3/6

Type
Edge

Source

CH1

Mode

Auto

Slope /

Coupling

CH1/2/Ext/Line

Auto/ Normal

To Slope/Coupling

Edge Trigger

Select edge trigger type

Edge

Select trigger source

Source

Go to slope/coupling menu (page

39)

Slope/Coupling

Select trigger mode

Mode

Type

Pulse

Source

CH1

Mode

Auto

Slope /

Coupling

When <

20.0ns
To Slope/Coupling

>/ </ =/ =

20ns~10s

CH1/2/Ext/Line

Pulse Trigger

Auto/ Normal

Select pulse trigger type

Type

Select trigger source

Source

Select pulse trigger condition and
pulse width

When →VAR

Go to slope/coupling menu (page

39)

Slope/Coupling

Select trigger mode

Mode

Trigger key 4/6

GDS-1000A-U Series User Manual

38

Trigger key 5/6

LF/ HF/ Off

On/ Off

/

Slope

Coupling

AC

Rejection

Off

Previous

Menu

Noise Rej

Off

AC/ DC

Coupling/Slope

Select trigger slope type

Slope

Select trigger coupling mode

Coupling

Select frequency rejection

Rejection

Turn noise rejection on/off

Noise Rej

Go back to previous menu

Previous Menu

Holdoff

40.0ns
Set to

Minimum

40ns~2.5s

Trigger Holdoff

Select Holdoff time

VAR

Set to minimum Holdoff time

Set to Minimum

Trigger key 6/6

QUICK REFERENCE

39

GDS-1000A-U Series User Manual

Hardcopy

Menu

More

ProbeComp

Menu

Language

English

To Probe
Comp menu

To Hardcopy
menu

English/
Chinese(T) etc

Utility

Utility #2 menu

System

Info.

Go to hardcopy menu

Hardcopy

Go to probe compensation menu

ProbeComp

Select language

Language

Show system information

System Info.

Go to the next Utility menu

More

Go-NoGo

Menu

/

More

No Go When

Data logging

Menu

Utility

To Go-NoGo
menu

To Data
Logging menu

To Utility #3 menu

Go to the Go-NoGo menu

Go-NoGo

Set the NoGo conditions to inside

/outside limits

No Go When

Go to the Data Logging Menu

Data Logging

Go to the next Utility menu

More

Utility key 1/11 (Utility #1)

Utility 2/11 (Utility #2)

40

QUICK REFERENCE

Self CAL

Menu

Calibration

USB Port

Auto Detect

Auto Detect
Computer
Printer

More

To Utility #1 menu

To Self CAL menu

Enter self calibration

Self CAL

Select USB port interface

USB Port

Go to the first Utility menu

More

Function
Save All

Previous

Menu

On/ Off

Ink Saver

Off

Hardcopy – Save All

Mem Leng

USB 1M

USB Normal
USB 1M/2M

Fast/ Detail

CSV Format

Fast

Select Hardcopy function

Function

Turn on/off Ink saver

Ink Saver

Set the memory length

Mem Leng

Change CSV format

CSV Format

Go to previous menu

Previous Menu

Utility key 3/11 (Utility #3)

Utility key 4/11 (Hardcopy -Save All)

41

GDS-1000A-U Series User Manual

Function

Printer

Previous

Menu

On/ Off

Ink Saver

Off

Hardcopy – Printer

Page Size

Default

Default/ 4X6/ A4

Select Hardcopy function

Function

Turn on/off Ink saver

Ink Saver

Set default page size

Page Size

Go to previous menu

Previous Menu

Function

Save Image

Previous

Menu

On/ Off

Ink Saver

Off

Hardcopy – Save Image

Select Hardcopy function

Function

Turn on/off Inksaver

Ink Saver

Go to previous menu

Previous Menu

Utility key 5/11 (Hardcopy -Printer)

Utility key 6/11 (Hardcopy -Save Image)

42

QUICK REFERENCE

Wave Type

( only)

1k ~ 100k

( only)

5% ~ 95%

Default

1kHz

/

Previous

Menu

Frequency

1 K

Duty Cycle

50%

Probe compensation

Select probe compensation signal

Wave Type

Set frequency for square wave

Frequency→VAR

Set duty cycle for square wave

Duty Cycle→VAR

Go to previous menu

Previous Menu

0.4%~40%

0.4DIV~40DIV

Max/Min/Auto

To previous
menu

Edit

Template

Max

Auto: CH1, CH2
Max|Min: Ref A/
Ref B, W01~W15

Source

W 01

Tolerance

0.4%

Save &

Create

Previous

Menu

Switch between templates

Template

Select the template source

Source

Set the tolerance (% or Divisions)

Tolerance →VAR

Save the template

Save & Create

Go back to previous menu

Previous Menu

Utility key 7/11 (Probe compensation)

Utility key 8/11 (Go-NoGo)

43

GDS-1000A-U Series User Manual

Off

CH1/CH2

On/Off

To previous
menu

Data logging

Data logging

Source

CH1

Setup

File

Utilities

Previous

Menu

(USB only)
To File Utilities

To the Edit
menu

Turn Data Logging On/Off

Data logging

Set the logging source

Source

Go to the Data Logging Edit menu

Setup

Go to the File Utilities menu

File Utilities

Go back to previous menu

Previous Menu

2 secs~30 mins

Waveform/Image

To previous
menu

Edit

Save

Waveform

Interval

2 secs

Duration

5 mins

Previous

Menu

5 mins~100 hrs

Save the logs as waveform data or
as image files

Save

Set the logging interval

Interval→VAR

Set the duration of the record log

Duration→VAR

Go back to previous menu

Previous Menu

Vertical

Self Cal.

Start Vertical
Calibration

Start Vertical Calibration

Vertical

Utility key 9/11 (Data Logging 1/2)

Utility key 10/11 (Data Logging 2/2)

Utility key 11/11 (Self CAL Menu)

44

QUICK REFERENCE

Here are the factory installed panel settings which
appear when pressing the Save/Recall key→
Default Setup.

Default

Setup

Save/Recall

Acquisition

Mode: Normal

Channel

Scale: 2V/Div

Invert: Off

Coupling: DC

Probe attenuation
voltage: x1

BW limit: Off

Channel 1 & 2: On

Cursor

Source: CH1

Cursor: Off

Display

Type: Vectors

Accumulate: Off

Grid: Full

Horizontal

Scale: 2.5us/Div

Mode: Main Timebase

H Pos Adj: Fine

Hor Pos: 0

Math

Type: + (Add)

Position: 0.00 Div

Unit/Div: 2V

Measure

Item: Vpp, Vavg, Frequency, Duty Cycle, Rise
Time

Trigger

Type: Edge

Source: Channel1

Mode: Auto

Slope:

Coupling: DC

Rejection: Off

Noise Rejection: Off

Utility

Hardcopy: SaveImage,
InkSaver On

ProbeComp: Square
wave, 1k, 50% duty cycle

Go-NoGo

Go-NoGo: Off

Source: CH1

When:

Violating: Stop

Default Settings

(Continued)

45

GDS-1000A-U Series User Manual

Data Logging

Data logging: Off

Source: CH1

Setup: Waveform

Interval: 2 secs

Duration: 5 mins

The Help key shows the contents of the built-in
help support. When you press a function key, its
descriptions appear in the display.

Help

Applicable keys

Acquire Display Utility Help

Run/Stop

Autoset

Cursor HardcopyMeasure Save/Recall

(Vertical)

CH 1 MATH CH 2

(Horizontal)

MENU

(Trigger)

MENU

FORCE

SINGLE

Procedure

1. Press the Help key. The

display changes to the Help
mode.

Help

2. Press a functional key to

access its help contents.
(example: Acquire key)

Acquire

3. Use the Variable knob to

scroll the Help contents up
and down.

VARIABLE

4. Press the Help key again to

exit the Help mode.

Help

Built-in Help

46

MEASUREMENT

Activating a
channel

To activate an input channel,
press the Channel key, CH1 or
CH2. The channel indicator
appears at the left side of the
display and the channel icon
changes accordingly.

CH 1

or

CH 2

MEASUREMENT

The Measurement chapter describes how to

properly observe a signal using the oscilloscope’s

basic functions, and how to observe a signal in a
detailed manner using some of the advanced
functions such as:

Automatic measurements, cursor measurements,
and math operations.

Basic Measurements

This section describes the basic operations required in capturing and
viewing an input signal. For more detailed operations, see the
following chapters.

 Measurements → from page 47
 Configuration → from page 78

Activating a channel

(Continued on next page)

47

Channel icon

Channel
indicator

Channel 1 off Channel 1 on

De-activating a
channel

To de-activate the channel, press the Channel key
twice (once if the channel menu is already
selected).

Background

The Autoset function automatically configures the
panel settings to the best viewing conditions, in the
following way.

 Selecting the horizontal scale
 Positioning the waveform horizontally
 Selecting the vertical scale
 Positioning the waveform vertically
 Selecting the trigger source channel
 Activating the channels

Autoset can be configured into two types of
modes, AC Priority Mode or Fit Screen Mode.

AC Priority mode will scale the waveform to the
screen removing any DC component.

Fit Screen Mode will fit the waveform to the best
scale, including any DC components (offset).

Using Autoset

GDS-1000A-U Series User Manual

48

MEASUREMENT

Procedure

1. Connect the input signal to

the oscilloscope and press
the Autoset key.

Autoset

2. The waveform(s) appears in the center of the

display.

Undo option

Before Autoset After Autoset

Type Option

Undoing the
Autoset

To undo the Autoset, press
Undo (available for a few
seconds).

Undo

Adjusting the
trigger level

If the waveform is still
unstable, try adjusting the
trigger level up or down by
using the Trigger Level knob.

LEVEL

Change Modes

To change the type of mode,
press Type (available for a few
seconds). The Type icon will
change to next type.

Type

AC Priority

Type

Fit Screen, AC Priority

The next time the Autoset key is pressed, the new
mode will be activated.

49

GDS-1000A-U Series User Manual

Fit Screen AC Priority

Limitation

Autoset does not work in the following situation.

 Input signal frequency less than 2Hz
 Input signal amplitude less than 30mV

Background

In the trigger Run mode, the oscilloscope
constantly searches for a trigger condition and
updates the signal onto the display when the
condition is met.

In the trigger Stop mode, the oscilloscope stops
triggering and thus the last acquired waveforms
stay in the display. The trigger icon at the top of
the display changes into Stop mode.

Pressing the Trigger Run/Stop key
switches between the Run and Stop
mode.

Run/Stop

Trigger Run mode Trigger Stop mode

Stop icon

Auto or
Trig icon

Running and stopping the trigger

50

MEASUREMENT

Waveform
operation

Waveforms can be moved or scaled in both the
Run and Stop mode. For details, see page 85
(Horizontal position/scale) and page 91 (Vertical
position/scale).

Setting the
horizontal
position

The horizontal position knob
moves the waveform left or right.

The position indicator moves along with the
waveform and the distance from the center point is
displayed as the offset in the upper side of the
display.

Horizontal offset

Position indicator

Selecting the
horizontal scale

To select the timebase (scale), turn
the TIME/DIV knob; left (slow) or
right (fast).

TIME/DIV

Range

1ns/Div ~ 10s/Div, 1-2.5-5 increment

Changing the horizontal position and scale

For more detailed configurations, see page 85.

51

GDS-1000A-U Series User Manual

Horizontal scale: 50us/div Horizontal scale: 250us/div

Set vertical
position

To move the waveform up or
down, turn the vertical position
knob for each channel.

As the waveform moves, the vertical position of
the cursor appears at the bottom left corner of the
display.

Run/Stop mode

The waveform can be moved
vertically in both Run and Stop
mode.

Select vertical
scale

To change the vertical scale,
turn the VOLTS/DIV knob; left
(down) or right (up).

VOLTS/DIV

Range

2mV/Div ~ 10V/Div, 1-2-5 increments

The vertical scale indicator for each channel on the
bottom left of the display changes accordingly.

Changing the vertical position and scale

For more detailed configuration, see page 91.

52

MEASUREMENT

Background

This section introduces how to use
the probe compensation signal for
general usage, in case the DUT
signal is not available or to get a
second signal for comparison. For
probe compensation details, see
page 132.

Note: The frequency accuracy and duty factor are
not guaranteed. Therefore the signal should not be
used for reference purposes.

Waveform type

Square waveform used for probe
compensation. 1k ~ 100kHz, 5% ~
95%.

Demonstration signal for showing
the effects of peak detection. See page
78 for peak detection mode details.

View the probe
compensation
waveform

1. Connect the probe between the compensation

signal output and Channel input.

VOLTS/DIV VOLTS/DIV TIME/DIV

CH 1 MATH CH 2 MENU MENU

Acquire

Display

Utility Help

Run/Stop

VARIABLE

FORCE

Autoset

Cursor

SINGLE

Hardcopy

Measure

Save/Recall

LEVEL

VERTICAL HORIZONTAL TRIGGER

CH1

CAT300V

MW15pF

MAX. 300Vpk

1

CH2 EXT TRIG

CAT300V

MW15pF

MAX. 300Vpk

1

X Y

X
10

X
1

CH1

x1

x10

2. Press the Utility key.

Utility

3. Press ProbeComp.

ProbeComp

Menu

Using the probe compensation signal

53

GDS-1000A-U Series User Manual

4. Press Wave type repeatedly

to select the wave type.

Wave Type

5. (For only) To change

the frequency, press
Frequency and use the
Variable knob.

Frequency

1 K

VARIABLE

Range

1kHz ~ 100kHz

6. (For only) To change

the duty cycle, press Duty
Cycle and use the Variable
knob.

Duty Cycle

50%

VARIABLE

Range

5% ~ 95%

Probe
compensation

For probe compensation details, see page 132.

54

MEASUREMENT

Overview

Voltage type

Time type

Delay type

Vpp
Vmax
Vmin
Vamp
Vhi
Vlo
Vavg
Vrms
ROVShoot
FOVShoot
RPREShoot
FPREShoot

Frequency
Period
RiseTime
FallTime
+Width

-Width
Dutycycle

FRR
FRF
FFR
FFF
LRR
LRF
LFR
LFF

Voltage
measurement
items

Vpp

Difference between positive
and negative peak voltage
(=Vmax − Vmin)

Vmax

Positive peak voltage.

Vmin

Negative peak voltage.

Vamp

Difference between global
high and global low voltage
(=Vhi − Vlo)

Vhi

Global high voltage.

Automatic Measurements

The automatic measurement function measures input signal
attributes and updates them in the display. Up to 5 automatic
measurement items can be updated at any one time on the side
menus. All automatic measurement types can be displayed on
screen if necessary.

Measurement items

55

GDS-1000A-U Series User Manual

Vlo

Global low voltage.

Vavg

Averaged voltage of the first
cycle.

Vrms

RMS (root mean square)
voltage.

ROVShoot

Rise overshoot voltage.

FOVShoot

Fall overshoot voltage.

RPREShoot

Rise preshoot voltage.

FPREShoot

Fall preshoot voltage.

Time
measurement
items

Freq

Frequency of the waveform.

Period

Waveform cycle time
(=1/Freq).

Risetime

Rising time of the pulse
(~90%).

Falltime

Falling time of the pulse
(~10%).

+Width

Positive pulse width.

–Width

Negative pulse width.

Duty Cycle

Ratio of signal pulse
compared with whole cycle
=100x (Pulse Width/Cycle)

Delay
measurement
items

FRR

Time between:
Source 1 first rising edge and
Source 2 first rising edge

56

MEASUREMENT

FRF

Time between:
Source 1 first rising edge and
Source 2 first falling edge

FFR

Time between:
Source 1 first falling edge and
Source 2 first rising edge

FFF

Time between:
Source 1 first falling edge and
Source 2 first falling edge

LRR

Time between:
Source 1 first rising edge and
Source 2 last rising edge

LRF

Time between:
Source 1 first rising edge and
Source 2 last falling edge

LFR

Time between:
Source 1 first falling edge and
Source 2 last rising edge

LFF

Time between:
Source 1 first falling edge and
Source 2 last falling edge

Background

Automatic measurements can be restricted to a
specific area (gating). When cursors are turned on,
the area between the cursors is used for automatic
measurements. When cursors are turned off,
measurements are derived from all the points that
are displayed on screen.

Turn gating on

1. Turn on cursors to enable

gated automatic
measurements.

page 61

Automatic measurement gating

57

GDS-1000A-U Series User Manual

2. Press the Measure key.

Measure

3. The measurement results appear on the menu

bar, constantly updated. All measurements are
derived from the cursor positions. See
Automatically measuring the input signals for
more details (page 58).

X

1

X

2

Horizontal Cursor

Gating

Turn gating off

4. Turn off cursors to turn off

gated automatic
measurements.

page 61

Viewing the
measurement
result

1. Press the Measure key.

Measure

2. The measurement results appear on the menu

bar, constantly updated. 5 measurement slots
(F1 to F5) can be customized.

Automatically measuring the input signals

58

MEASUREMENT

Editing a
measurement
item

3. Press the corresponding

menu key (F1~F5) to select
the measurement slot to be
edited.

Voltage

Vpp

4. The editing menu appears

Change
measurement
item

5. Use the Variable knob to

select a different
measurement item.

VARIABLE

Change
measurement
source

6. Press Source 1 repeatedly to

change Source1 from CH1
to CH2 or MATH.

Source 1

CH1

Range

CH1, 2, Math

59

GDS-1000A-U Series User Manual

7. Press Source 2 repeatedly to

change the channel for
Source2.

Source 2

CH2

Range

CH1, 2, Math

View all
measurements

8. Press F3 to view all

measurement items.

Voltage

Vpp

9. All the measurements

appear in the center of the
screen.

10. Press F3 again to return.

Note: All the editing operations can still be
performed when viewing all the measurement
items.

11. Press Previous Menu to

confirm the item selection
and to go back to the
measurement results view.

Previous

Menu

60

MEASUREMENT

Procedure

1. Press the Cursor key. The

cursors appear in the
display.

Cursor

2. Press X

↔

Y to select the

horizontal (X1&X2) cursor.

X↔Y

3. Press Source repeatedly to

select the source channel.

Source

CH1

Range

CH1, 2, MATH

4. The cursor measurement results will appear in

the menu, F2 to F4.

Parameters

X1

Time position of the left cursor. (relative to
zero)

X2

Time position of the right cursor. (relative
to zero)

X1X2

The difference between the X1 and X2.

∆: us

The time difference between X1 and X2.

f: Hz

The time difference converted to
frequency.

V/A

The voltage/current difference from X1
and X2.

Cursor Measurements

Cursor lines, horizontal or vertical, show the precise position of the
input waveforms or the math operation results. The horizontal
cursors can track time, voltage/current* and frequency, whilst the
vertical cursors can track voltage/current*. All measurements are
updated in real-time. *probe type dependant (page 94).

Using the horizontal cursors

61

GDS-1000A-U Series User Manual

M1:dB

Position of the left cursor in dB.

M2:dB

Position of the right cursor in dB.

∆: dB

The dB difference between M1 and M2.

Div:

The frequency per division.

Moving the
horizontal
cursors

To move the left cursor, press
X1 and then use the Variable
knob.

X1

-5.000uS

0.000uV

To move the right cursor, press
X2 and then use the Variable
knob.

X2

5.000uS

0.000uV

To move both cursors at once,
press X1X2 and then use the
Variable knob.

X1X2

10.00uS

100.0kHz

0.000uV

∆ :
f :

Remove cursors

Press Cursor to remove the
onscreen cursors.

Cursor

Procedure

1. Press the Cursor key.

Cursor

2. Press X

↔

Y to select the

vertical (Y1&Y2) cursor.

X↔Y

3. Press Source repeatedly to

select the source channel.

Source

CH1

Range

CH1, 2, MATH

4. The cursor measurement results will appear in

the menu.

Parameters

Y1

Voltage level of the upper cursor

Y2

Voltage level of the lower cursor

Using the vertical cursors

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MEASUREMENT

Y1Y2

The difference between the upper and
lower cursor

V/A

The voltage/current difference (Y1-Y2).

Moving the
vertical cursors

To move the upper cursor,
press Y1 and then use the
Variable knob.

Y1

123.4mV

To move the lower cursor,
press Y2 and then use the
Variable knob.

Y2

12.9mV

To move both cursors at once,
press Y1Y2 and then use the
Variable knob.

Y1Y2

10.5mV

Remove cursors

Press Cursor to remove the
onscreen cursors.

Cursor

Addition (+)

Adds the amplitude of CH1 & CH2 signals.

Subtraction (–)

Extracts the amplitude difference between CH1 &
CH2.

Multiplication (×)

Multiplies CH1 and CH2.

FFT

Performs a FFT calculation on a signal. Four types
of FFT windows are available: Hanning, Flattop,
Rectangular, and Blackman.

Math Operations

The Math operations can add, subtract, multiply or perform
FFT/FFT RMS on the input waveforms. The resulted waveform can
be measured using the cursors, and saved or recalled just like
normal input signals.

Overview

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GDS-1000A-U Series User Manual

FFT RMS

Performs a FFT RMS calculation on a signal. RMS
is similar to FFT, however the amplitude is
calculated as RMS and not dB. Four types of FFT
windows are available: Hanning, Flattop,
Rectangular, and Blackman.

Hanning FFT
window

Frequency resolution

Good

Amplitude resolution

Not good

Suitable for....

Frequency measurement on
periodic waveforms

Flattop FFT
window

Frequency resolution

Not good

Amplitude resolution

Good

Suitable for....

Amplitude measurement on
periodic waveforms

Rectangular FFT
window

Frequency resolution

Very good

Amplitude resolution

Bad

Suitable for....

Single-shot phenomenon
(this mode is the same as
having no window at all)

Blackman FFT
window

Frequency resolution

Bad

Amplitude resolution

Very good

Suitable for....

Amplitude measurement on
periodic waveforms

Procedure

1. Activate both CH1 and

CH2.

CH 1

CH 2

2. Press the Math key.

M

A

TH

Adding, subtracting or multiplying signals

64

MEASUREMENT

3. Press Operation repeatedly

to select addition (+),
subtraction (–) or
multiplication (×).

Operation

CH1+CH2

4. The math measurement

result appears in the
display.

Unit/Div

2V

5. To move the math result

vertically, use the Variable
knob. The position will be
displayed in Position.

VARIABLE

Position

0.00 Div

6. To clear the math result

from the display, press the
Math key again.

M

A

TH

Procedure

1. Press the Math key.

M

A

TH

2. Press Operation repeatedly

to select FFT or FFT RMS.

Operation

FFT

3. Press Source repeatedly to

select the source channel.

Source

CH1

4. Press Window repeatedly to

select the FFT window type.

Window

Hanning

Using the FFT function

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GDS-1000A-U Series User Manual

5. The FFT result appears. The horizontal scale

changes from time to frequency, and the
vertical scale from voltage to dB or RMS.

6. To move the FFT waveform

vertically, press Vertical
repeatedly until Div is
selected. Use the Variable
knob to change the vertical
scale.

Vertical

2V

0.00 Div

VARIABLE

Range

–12.00 Div ~ +12.00 Div

7. To select the vertical scale of

an FFT waveform, press
Vertical repeatedly until dB
is selected. Use the Variable
knob to change the vertical
scale.

Vertical

1 dB

0.00 Div

VARIABLE

Range

1, 2, 5, 10, 20 dB/Div

8. To select the vertical scale of

an FFT rms waveform, use
the VOLTS/DIV knob to
change the vertical scale.
The scale will be shown in
the Vertical soft-key.

VOLTS/DIV

Range

Volts/Div

9. To zoom in on the FFT/FFT

rms waveform, press Zoom
repeatedly until X is
selected. Use the Variable
knob to change the Zoom
level.

Zoom

1X

0.0000Hz

VARIABLE

Range

1/2/5/10/20X

66

MEASUREMENT

10. To move the FFT/FFT rms

waveform horizontally,
press Zoom repeatedly until
Hz is selected. Use the
Variable knob to change the
horizontal position.

Zoom

1X

0.0000Hz

VARIABLE

Range

0~50.000MHz

11. To clear the FFT result from

the display, press the Math
key again.

M

A

TH

Background

Go-NoGo testing checks if a waveform conforms to
a user-specified maximum and minimum
boundary (template). The testing can be set to stop
or continue each time the template has or has not
been violated by the input waveform.

Settings

Item

Default

Details

NoGo criteria: When inside
or outside the boundary

Inside

Page 68

Source

Channel 1

Page 68

Test continue or stop when
NoGo occurs

Stop

Page 69

Boundary (template) –
selects the minimum and
maximum boundaries
(template) from a single
waveform

Auto (0.4%)

Page 69

Run Tests

Page 73

Go No-Go Testing

Overview

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GDS-1000A-U Series User Manual

Procedure

1. Press the Utility key.

Utility

2. Press the More key.

More

3. Press No Go When

repeatedly to select the
NoGo conditions.

No Go When

NoGo when the waveform is
inside the boundary (template)

NoGo when the waveform is
outside of the boundary
(template)

Procedure

1. Press the Utility key.

Utility

2. Press the More key.

More

3. Press the Go-NoGo Menu

key.

Go-NoGo

Menu

4. Press Source repeatedly to

select the source channel
(CH1 or CH2).

Source

CH1

Edit: NoGo When

Edit: Source

68

MEASUREMENT

Procedure

1. Press the Utility key.

Utility

2. Press the More key.

More

3. Press the Go-NoGo Menu

key.

Go-NoGo

Menu

4. Press Violating repeatedly to

select the NoGo conditions.

Violating

Stop

Stop

Stops the test when the NoGo
conditions have been met.

Continue

The tests continue even when the
NoGo conditions have been met.

Background

The NoGo template sets the upper and lower
amplitude boundary. Two methods are available:
Min/Max and Auto.

Min/Max

Selects the upper boundary (Max)
and lower boundary (Min) as
separate waveforms, from the
internal memory. The upper
boundary is saved to Ref A, the
lower boundary is saved to Ref. B.

Advantage: The template shape
and distance (allowance) between
the source signal are fully
customizable.

Edit: NoGo Violation Conditions

Edit: Template (boundary)

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GDS-1000A-U Series User Manual

Disadvantage: The waveforms
(templates) have to be stored
internally prior to this selection.

Auto

Creates the upper and lower
boundary (template) from the
source signal, not from an
internally stored waveform.

Advantage: No need to store the
waveforms prior to this selection.

Disadvantage: The template shape
is proportional to the source
signal. The distance (allowance)
between the source signal and the
upper and lower template is the
same.

Max/Mix

1. The template is based on the source signal.

Ensure the source signal appears on the
display.

2. Press the Utility key.

Utility

3. Press the More key.

More

4. Press the Go-NoGo Menu

key.

Go-NoGo

Menu

5. Press the Template Edit key.

Template

Edit

6. Press Template repeatedly to

select the upper (Max) or
lower (Min) boundaries.

Template

Max

70

MEASUREMENT

7. Press Source and use the

Variable knob to select the
waveform template.

Source

W 01

VARIABLE

Max

Waveform A: Ref A, W01~W15

Min

Waveform B: Ref B, W01~W15

8. Press Position and use the

Variable knob to set the
waveform amplitude.

Source

W 01

VARIABLE

9. Repeat steps 5-7 for the other template setting

(Max or Min).

10. When both Max and Min

templates have been
configured, press Save &
Create to save the templates.

Save &

Create

Min: Waveform B

Max: Waveform A

Position

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GDS-1000A-U Series User Manual

Auto

1. The template is based on the source signal.

Ensure the source signal appears on the
display.

2. Press the Utility key.

Utility

3. Press the More key.

More

4. Press the Go-NoGo Menu

key.

Go-NoGo

Menu

5. Press the Template Edit key.

Template

Edit

6. Press Template repeatedly to

select the Auto template.

Template

Auto

7. Press Source and use the

Variable knob to select the
template source.

Source

CH1

VARIABLE

Source

CH1, CH2

8. Press Tolerance repeatedly to

choose the tolerance units,
% or Div. Use the Variable
knob to set the tolerance.
The tolerance is for both the
horizontal and vertical axis.

Tolerance

0.4%

VARIABLE

%

0.4% ~ 40.0%

72

MEASUREMENT

Div

0.04 Div ~ 4.0 Div

9. When the Auto template has

been configured, press Save
& Create to save the
template.

Save &

Create

Auto template

Source waveform

Tolerance

Procedure

1. Press the Utility key.

Utility

2. Press the More key.

More

3. Press the Go-NoGo Menu

key.

Go-NoGo

Menu

Ensure the source signal and boundary templates
appear on the screen.

Run Go-NoGo Tests

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GDS-1000A-U Series User Manual

4. Press Go-NoGo. The test

starts and stops according to
the conditions set on page
68, 69. To stop the test that
has already started, press
Go-NoGo again.

Go-NoGo

On

5. The test results appear in

the Ratio soft-key. The
numerator denotes the total
number of failed tests. The
denominator denotes the
total number of tests.

Ratio:

2 BMP
9 BMP

Numerator

Number of “failed“ tests.

Denominator

Total number of tests.

Background

The Data logging function allows you to log data
or a screen image over timed intervals for up to
100 hours to a USB flash drive.

The data or images are stored to a USB flash drive
in a directory named LogXXXX. LogXXXX is
incremented each time the data logging function is
used.

The files saved in the LogXXXX directory are
named DSXXXX.CSV, or DSXXXX.BMP for data or
image files, respectively. At each timed interval
data or an image file is saved and the file number
incremented. For example, DS0000 is the first
logged data, DS0001 is the second and so on.

Data Logging

Overview

74

MEASUREMENT

Procedure

1. Press the Utility key.

Utility

2. Press the More key.

More

3. Press the Data logging Menu

key.

Data logging

Menu

4. Press Source repeatedly to

select the source channel
(CH1 or CH2).

Source

CH1

Background

The logging function must set the type of data that
will be logged (waveform/image), the capture
interval time and the duration of the data logging.

Procedure

1. Press the Utility key.

Utility

2. Press the More key.

More

3. Press the Data logging Menu

key.

Data logging

Menu

4. Press the Setup key.

Setup

Edit: Source

Edit: Setup Parameters

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GDS-1000A-U Series User Manual

5. Press Save repeatedly to log

data or screen images.

Save

Waveform

6. Press Interval and use the

Variable knob to select the
interval time.

Source

W 01

VARIABLE

Interval
time

2 secs~ 2min (duration = 5 min)

2 secs~ 5 min (duration 5~ 30 min)

2 secs~ 30 min (duration 30+ min)

7. Press Duration and use the

Variable knob to set the
duration time.

Duration

5 mins

VARIABLE

Duration

5 mins ~ 100 hours

8. Press Previous menu to

return to the Data logging
menu. Data logging is now
ready to begin.

Previous

Menu

76

MEASUREMENT

Background

Ensure the data source (page 75) and data logging
setup has been set (page 75).

Procedure

1. Insert a USB flash drive into

the USB front panel port.

2. Press the Utility key.

Utility

3. Press the More key.

More

4. Press the Data logging Menu

key.

Data logging

Menu

5. Press Data logging to turn

data logging On.
Data/image files start
logging to the USB flash
drive automatically. To stop
the Data logging, press the
Data logging key again.

On

Data logging

Run Data logging

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GDS-1000A-U Series User Manual

Procedure

1. Press the Acquire key.

Acquire

2. Select the acquisition mode

between Normal, Average
and Peak Detect.

Normal

Peak

Detect

Average

Range

Normal

All of the acquired data is used to
draw the waveform.

CONFIGURATION

The Configuration chapter describes how to
configure panel settings to make measurements
and observations suited to the application needs.

Acquisition

The acquisition process samples the analog input signals and
converts them into digital format for internal processing. You may
select the normal, average, or peak detect acquisition mode.

Selecting the acquisition mode

78

CONFIGURATION

Average

Multiple data is averaged to form a
waveform. This mode is useful for
drawing a noise-free waveform. To
select the number, press Average
repeatedly.

Average number: 2, 4, 8, 16, 32, 64, 128,
256

Peak detect

To activate the Peak detect mode,
press Peak-Detect. Only the minimum
and maximum value pairs for each
acquisition interval (bucket) are used.
This mode is useful for catching
abnormal glitches in a signal.

Peak detect effect
using the probe
comp. waveform

1. One of the probe

compensation waveforms
can demonstrate the peak
detection mode. Connect the
probe to the probe
compensation output.

2. Press the Utility key.

Utility

3. Press ProbeComp.

ProbeComp

Menu

4. Press Wave Type and select

the waveform.

Wave Type

5. Press the Autoset key. The

oscilloscope positions the
waveform in the center of
the display.

Autoset

6. Press the Acquire key.

Acquire

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GDS-1000A-U Series User Manual

7. Press Normal.

Normal

8. Press Peak-Detect and see

that a spike noise is
captured.

Peak

Detect

Example

The peak detect mode reveals the occasional glitch.

Normal mode

Peak detect mode

Background

When delay time is ON, the displayed output is
delayed for a defined amount of time from the
trigger point. Using the delay function is useful
for observing an area of the waveform that occurs
some time after the trigger point.

Delay On

With Delay On the expansion point and trigger
point become separated by the amount of delay
time. As the delay time is increased the trigger
point moves left from the expansion point. When
the horizontal scale is adjusted, the waveform
expands from the expansion point, not the trigger
point.

Selecting Delay mode

80

CONFIGURATION

Expansion

Point

Horizontal scale

Trigger

Point

Expansion

Point

Horizontal scale

Trigger

Point

Delay Off

With Delay Off the expansion point and trigger
point are always in the same position. Thus when
the horizontal scale is adjusted, the waveform
expands from the trigger point.

Expansion

Point

Horizontal scale

Trigger

Point

Horizontal scale

Expansion

Point

Trigger

Point

Procedure

1. Press the Acquire key.

Acquire

2. Press Delay On/Off to

toggle Delay On/Off.

Delay

On

3. Use the Horizontal Position

knob to increase or decrease
the delay time when Delay
is set to On.

4. Adjust the horizontal scale

to zoom into the waveform.

TIME/DIV

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Background

The oscilloscope automatically switches between
two sampling modes, Real-time and Equivalent­time, according to the number of active channels
and sampling rate.

Real-time
sampling

Once sampled data is used to reconstruct a single
waveform. Short-time events might get lost if the
sampling rate gets too high. This mode is used
when the sampling rate is relatively low (1GSa/s
or lower).

Equivalent-time
sampling

Multiple numbers of sampled data are
accumulated to reconstruct a single waveform.
ETS restores more waveform detail but takes
longer to update the waveform. This mode is used
when the sampling rate becomes higher than
1GSa/s. The maximum equivalent-time sampling
rate is 25GSa/s.

Real time vs Equivalent time sampling mode

82

CONFIGURATION

Procedure

1. Press the Display key.

Display

2. Press Type repeatedly to

select the waveform
drawing.

Type

Vectors

Types

Dots

Only the sampled dots are displayed.

Vectors

The sampled dots are connected by
lines.

Background

Accumulation preserves the old waveform
drawings and overwrites new waveforms on top
of it. It is useful for observing waveform variation.

Procedure

1. Press the Display key.

Display

2. Press Accumulate to turn on

the waveform accumulation.

Accumulate

On

3. To clear the accumulation

and start it over (refresh),
press Refresh.

Refresh

Display

The Display section describes how to configure the display settings:
drawing type, waveform accumulation, contrast adjustment, and
grid settings.

Selecting vector or dot drawing

Accumulating the waveform

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GDS-1000A-U Series User Manual

Example

Accumulation off

Accumulation on

Procedure

1. Press the Display key.

Display

2. Press Contrast.

Contrast

3. Turn the Variable knob left

to lower the contrast (dark
display) or right to raise the
contrast (bright display).

VARIABLE

Procedure

1. Press the Display key.

Display

2. Press the grid icon

repeatedly to select the grid.

Full

Parameters

Shows the full grid.

Shows the outer frame and X/Y axis.

Shows only the outer frame.

Adjusting the display contrast

Selecting the display grid

84

CONFIGURATION

Procedure

The horizontal position knob
moves the waveform left or
right. The position indicator at
the top of the display shows the
center and current position.

Center position

Moving right

Select horizontal
scale

To select the timebase (scale),
turn the TIME/DIV knob; left
(slow) or right (fast).

TIME/DIV

Range

1ns/Div ~ 50s/Div, 1-2.5-5-10 increment

The timebase indicator at the bottom of the display
updates the current horizontal scale.

Horizontal View

The Horizontal view section describes how to configure the
horizontal scale, position, waveform update mode, window zoom,
and X-Y mode.

Moving the waveform position horizontally

Selecting the horizontal scale

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GDS-1000A-U Series User Manual

Background

The display update mode is switched
automatically or manually according to the
horizontal scale.

Main mode

Updates the whole displayed waveform at once.
The main mode is automatically selected when the
horizontal scale (timebase) is fast.

Horizontal scale

≤100ms/div

Trigger

All modes available

Roll mode

Updates and moves the waveform gradually from
the right side of the display to the left. The Roll
mode is automatically selected when the
horizontal scale (timebase) is 50ms or slower.

When in the Roll mode, an indicator appears at the
bottom of the display. When in roll mode the
record length is 2M (1 channel) or 1M (2 channel).

Main mode

Roll mode

Timebase

≥50ms/div (≤1.25MS/s)

Trigger

Auto mode only

Selecting the Roll
mode manually

1. Press the Horizontal menu

key.

MENU

2. Press Roll. The horizontal

scale automatically becomes
50ms/div and the
waveform starts scrolling
from the right side of the
display (If the oscilloscope
is already in the Roll mode,
there will be no change).

Roll

Selecting the waveform update mode

86

CONFIGURATION

Procedure/ range

1. Press the Horizontal Menu

key.

MENU

2. Press Window.

Window

3. Use the horizontal position

knob to move the zoom
range sideways, and
TIME/DIV knob to change
the zoom range width.

TIME/DIV

The width of the bar in the middle of the
display is the actual zoomed area.

Zoom range

1ns ~ 25s

4. Press Window Zoom. The

specified range gets
zoomed.

Window

Zoom

Example

Zoom width

Setting the zoom width Zooming in

Zooming the waveform horizontally

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GDS-1000A-U Series User Manual

Background

The X-Y mode compares the voltage of Channel 1
and Channel 2 waveforms in a single display. This
mode is useful for observing the phase relationship
between the two waveforms.

Procedure

1. Connect the signals to

Channel 1 (X-axis) and
Channel 2 (Y-axis).

2. Make sure both Channel 1

and 2 are activated.

CH 1

CH 2

3. Press the Horizontal key.

MENU

4. Press XY. The display

shows two waveforms in X­Y format; Channel 1 as X­axis, Channel 2 as Y-axis.

XY

Adjusting the X-Y
mode waveform

Horizontal position

CH1 Position knob

Horizontal scale

CH1 Volts/Div knob

Vertical position

CH2 Position knob

Vertical scale

CH2 Volts/Div knob

Example

Main mode XY mode

XY mode

Viewing waveforms in the X-Y mode

88

CONFIGURATION

Background

The horizontal adjustment menu allows markers to
be set at different times relative to the Horizontal
position marker at 0 seconds. Each marker is
linked to the mark directly before and after (in
time). There can be up to 30 markers linked
together.

1. Press the Horizontal menu

key twice to enter the
horizontal adjustment menu

MENU MENU

2. Press H Pos Adj to toggle

between coarse and fine
adjustments.

H Pos Adj

Fine

3. Adjust the horizontal

position with the horizontal
position knob.

Set marker

4. Press Set/Clear to create a

marker at the current
horizontal position.

Set/Clear

180.0uS

Delete marker

5. If there is already a marker

at the current horizontal
position press Set/Clear to
delete the current marker.

Set/Clear

180.0uS

Reset horizontal
position

6. Press Reset to reset the

horizontal position to 0
seconds when the trigger is
running, or to the last
position before the trigger
was stopped.

Reset

Hor Pos

Horizontal Adjustment Menu

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GDS-1000A-U Series User Manual

Navigate markers

7. Press Previous to go to the

previous marker.

Previous

180.0uS

8. Press Next to go to the next

marker.

Next

340.0uS

Position

Indicator

Marker

90

CONFIGURATION

Procedure

To move the waveform up or
down, turn the vertical position
knob for each channel.

Procedure

To change the vertical scale,
turn the VOLTS/DIV knob; left
(down) or right (up).

VOLTS/DIV

Range

2mV/Div ~ 10V/Div, 1-2-5 increments

Procedure

1. Press the Channel key.

CH 1

2. Press Coupling repeatedly to

select the coupling mode.

Coupling

Range

DC coupling mode. The whole
portion (AC and DC) of the signal
appears on the display.

Ground coupling mode. The display
shows only the zero voltage level as a
horizontal line. This mode is useful
for measuring the signal amplitude
with respect to the ground level.

Vertical View (Channel)

The Vertical view section describes how to set the vertical scale,
position, bandwidth limitation, coupling mode, and attenuation.

Moving the waveform position vertically

Selecting the vertical scale

Selecting the coupling mode

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GDS-1000A-U Series User Manual

AC coupling mode. Only the AC
portion of the signal appears on the
display. This mode is useful for
observing AC waveforms mixed with
DC components.

Background

Normally when the vertical scale is increased, the
scaled image is centered from ground. However a
signal with a voltage bias could be obscured when
the vertical scale is increased. The Expand Center
function expands the image from the center of the
signal, rather than ground.

Expand Ground

Position Indicator

Position Indicator

Expand Center

Position Indicator

Position Indicator

Expand Vertical Scale Center / Ground

92

CONFIGURATION

Procedure

1. Press the Channel key.

CH 1

2. Press F5 to toggle between

Expand Center and Expand
Ground.

Expand

Center

3. To change the vertical scale,

turn the VOLTS/DIV knob;
left (down) or right (up).

VOLTS/DIV

The vertical scale indicator on
the bottom left of the display
changes accordingly.

Procedure

1. Press the Channel key.

CH 1

2. Press Invert. The waveform

becomes inverted (upside
down) and the Channel
indicator in the display
shows a down arrow.

Invert

Off

Original

Inverted

Inverting the waveform vertically

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GDS-1000A-U Series User Manual

Background

Bandwidth limitation puts the input signal into a
20MHz (−3dB) low-pass filter. This function is
useful for cutting off high frequency noise to see
the clear waveform shape.

Procedure

1. Press the Channel key.

CH 1

2. Press BW Limit to turn on or

off the limitation. When
turned on, the BW indicator
appears next to the Channel
indicator in the display.

BW Limit

Off

Example

BW Limit Off

BW Limit On

Background

The probe can be set to either voltage or current.

A signal probe has an attenuation switch to lower
the original DUT signal level to the oscilloscope
input range, if necessary. The probe attenuation
selection adjusts the vertical scale so that the
voltage or current level on the display reflects the
real value, not the attenuated level.

Procedure

1. Press the Channel key.

CH 1

Limiting the waveform bandwidth

Probe attenuation level and type

94

CONFIGURATION

2. Press F4 repeatedly to select

voltage or current probes.

Voltage

x1

3. Use the variable knob to

edit the voltage or current
attenuation.

VARIABLE

4. The voltage/current scale in the channel

indicator changes accordingly. There is no
change in the waveform shape.

Range

0.1X~2000X (1-2-5 steps)

Note: The attenuation factor adds no influence on
the real signal; it only changes the voltage/current
scale on the display.

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GDS-1000A-U Series User Manual

Edge

Triggers when the signal crosses an amplitude
threshold in either a positive or negative slope.

Video

Extracts a sync pulse from a video format signal
and triggers on a specific line or field.

Pulse

Triggers when the pulse width of the signal
matches the trigger settings.

Indicators

Edge/Pulse

(CH1, Edge, Rising edge,
DC coupling)

Video

(CH1, Video, Positive
polarity, NTSC standard)

Trigger source

CH1, 2

Channel 1, 2 input signals

Line

AC mains signal

Ext

External trigger input
signal

EXT TRIG

Trigger mode

Auto

The oscilloscope updates the input signal
regardless of the trigger conditions (if
there is no trigger event, the oscilloscope
generates an internal trigger). Select this
mode especially when viewing rolling
waveforms at a slow timebase.

Trigger

The Trigger function configures the conditions by which the
oscilloscope captures the incoming signals.

Trigger type

Trigger parameter

96

CONFIGURATION

The Auto trigger status appears in the
upper right corner of the display.

Single

The oscilloscope acquires the
input signals once when a
trigger event occurs, then
stops acquiring. Pressing the
Single key again will repeat
the process.

SINGLE

The Single trigger status appears in the
upper right corner of the display.

(Searching)

(Triggered)

Normal

The oscilloscope acquires and updates
the input signals only when a trigger
event occurs.

The Normal trigger status appears in the
upper right corner of the display.

(Searching)

(Triggered)

Holdoff

The holdoff function defines the waiting period
before the GDS-1000A-U starts triggering again
after a trigger point. The Holdoff function ensures
a stable display.

Video standard
(video trigger)

NTSC

National Television System Committee

PAL

Phase Alternative by Line

SECAM

SEquential Couleur A Mémoire

Sync polarity
(video trigger)

Positive polarity

Negative polarity

Video line
(video trigger)

Selects the trigger point in the video signal.

field

1 or 2

97

GDS-1000A-U Series User Manual

line

1~263 for NTSC, 1~313 for PAL/SECAM

Pulse condition
(pulse trigger)

Sets the pulse width (20ns ~ 10s) and the triggering
condition.

>

Longer than

=

Equal to

<

Shorter than

≠

Not equal to

Trigger slope

Triggers on the rising edge.

Triggers on the falling edge.

Trigger coupling

AC

Triggers only on AC component.

DC

Triggers on AC+DC component.

Frequency
rejection

LF

Puts a high-pass filter and rejects the
frequency below 50kHz.

HF

Puts a low-pass filter and rejects the
frequency above 50kHz.

Noise rejection

Rejects noise signals.

Trigger level

LEVEL

Using the trigger level knob moves the
trigger point up or down.

Background

The Holdoff function defines the waiting period
before GDS-1000A-U starts triggering again after
the trigger point. The holdoff function is especially
useful for waveforms with two or more repetitive
frequencies or periods that can be triggered.

Panel operation

1. Press the Trigger menu key

twice.

MENU

MENU

2. To set the Holdoff time, use

the Variable knob. The
resolution depends on the
horizontal scale.

Range

40ns~2.5s

Configuring Holdoff

98

CONFIGURATION

Pressing Set to Minimum
sets the Holdoff time to the
minimum, 40ns.

Holdoff

40.0ns

Note: The holdoff function is automatically
disabled when the waveform update mode is
in Roll mode.

Procedure

1. Press the Trigger menu key.

MENU

2. Press Type repeatedly to

select edge trigger.

Type
Edge

3. Press Source repeatedly to

select the trigger source.

Source

CH1

Range

Channel 1, 2, Line, Ext

4. Press Mode repeatedly to

select the Auto or Normal
trigger mode. To select the
single trigger mode, press
the Single key.

Mode

Auto

SINGLE

Range

Auto, Normal

5. Press Slope/coupling to enter

into the trigger slope and
coupling selection menu.

Slope /

Coupling

6. Press Slope repeatedly to

select the trigger slope,
rising or falling edge.

Slope

Range

Rising edge, falling edge

Configuring the edge trigger

99

GDS-1000A-U Series User Manual

7. Press Coupling repeatedly to

select the trigger coupling,
DC or AC.

Coupling

AC

Range

DC, AC

8. Press Rejection to select the

frequency rejection mode.

Rejection

Off

Range

LF, HF, Off

9. Press Noise Rej to turn the

noise rejection on or off.

Noise Rej

Off

Range

On, Off

10. Press Previous menu to go

back to the previous menu.

Previous

Menu

Procedure

1. Press the Trigger menu key.

MENU

2. Press Type repeatedly to

select video trigger. The
video trigger indicator
appears at the bottom of the
display.

Type

Video

3. Press Source repeatedly to

select the trigger source
channel.

Source

CH1

Range

Channel 1, 2

Configuring the video trigger

100