Yokogawa DL1540C, DL1540CL User Manual

Digital Oscilloscope

IM 701530-01E

2nd Edition

Introduction

Notes

Thank you for purchasing the YOKOGAWA DL1540C/DL1540CL Digital Oscilloscope. This User’s Manual contains useful infor mation about the functions and operating procedures of the instrument, mainly DL1540C. It also contains precautions that should be observed during use. Main differences in the specifications between DL1540C and DL1540CL is that DL1540CL allows record length of up to 2M words. Due to these differences, functions and operations differ slightly among these models. For a detailed description, refer to the relevant sections of this manual. To ensure correct use of the instrument, please read this manual thoroughly before operating it. Keep the manual in a safe place for quick reference whenever a question arises. Two manuals are provided with the instrument in addition to this manual.

Manual Name Manual No. Description

DL1540C/1540CL IM701530-02E Describes basic operations only. Operation Guide

DL1540C/1540CL IM701530-11E Describes the communications functions Communication Interface for the GP-IB/RS-232-C interface.

User’s Manual

• The contents of this manual are subject to change without prior notice as a result of improvements in the instrument’s performance and functions. Display contents illustrated in this manual may differ slightly from what actually appears on your screen.

• Every effort has been made in the preparation of this manual to ensure the accuracy of its contents. However, should you have any questions or find any errors, please contact your nearest YOKOGAWA representative as listed on the back cover of this manual.

• Copying or reproduction of all or any part of the contents of this manual without YOKOGAWA’s permission is strictly prohibited.

Trademarks

MS-DOS is a registered trademark of Microsoft Corporation. HP-GL is a registered trademark of Hewlett-Packard Company. PostScript is a registered trademark of Adobe Systems Incorporated.

Revisions

1st Edition: December 1998 2nd Edition: May 2000

IM 701530-01E

Checking the Contents of the Package

Unpack the box and check the contents before operating the instrument. If the wrong instrument or accessories have been delivered, if some accessories are missing or if they appear abnormal, contact the dealer from which you purchased them.

Main Body

Check that the model name and suffix code given on the name plate of the rear panel match those on your order.

MODEL SUFFIX NO.

MODEL (Type Name)

701530 : DL1540C, 701540 : DL1540CL

Made in Japan

SUFFIX (Suffix Code)

Suffix Code Specifications

Power voltage 100-120 VAC/200-240 VAC Power cord -D UL/CSA Standards Power Cord (Part No.: A1006WD)

-F VDE Standard Power Cord (Part No.: A1009WD)

-Q BS Standard Power Cord (Part No.: A1054WD)

-R SAA Standard Power Cord (Part No.: A1024WD)

Options /B5 Built-in printer (real-time printing function)

*1 /F5 includes the enhanced trigger function for the DL1540CL. *2 /V1 and /C8 cannot be specified simultaneously. Example : DL1540C, UL/CSA standard power cord and full options → 701530-D/B5/E1/

F1/V1

[Maximum Rated Voltage: 125 V, Maximum Rated Current: 7 A]

[Maximum Rated Voltage: 250 V, Maximum Rated Current: 10 A]

[Maximum Rated Voltage: 240 V, Maximum Rated Current: 10 A]

/E1 With two additional 150 MHz probes (700998) /F1 Additional trigger (OR, Pattern, Width) /F5*1I2C-bus analysis function /C8*22.1-GB internal HDD /V1*2VGA output

NO. (Instrument No.)

When contacting the dealer from which you purchased your instrument, please quote the instrument No.

IM 701530-01E

Standard Accessories

Checking the Contents of the Package

The following standard accessories are supplied with the instrument. Make sure that all items are present and undamaged.

Power cord (one of the following power cords

is supplied according to the instrument's suffix codes)

UL/CSA standard A1006WD

150MHz probe (10:1, 1:1 selectable)(x2) 700998

Power supply fuse (in fuse holder) A1351EF

VDE standard A1009WD

Printer roll

∗

chart B9850NX

Front cover B9957DG

BS standard A1054WD

∗

User's manual (this manual) Communication interface manual Operation guide

Rubber feet(x4) A9088ZMx2

SAA standard A1024WD

Soft case B9918EZ

(x1) (x1) (x1)

IM 701530-01E

*1 For DL1540C/DL1540CL, a total of four passive probes are supplied (if the two

optional probes are included).

*2 A roll chart will be supplied only when the instrument is equipped with a built-in printer.

Checking the Contents of the Package

Optional Accessories

The following optional accessories are available. On receiving these optional accessories, make sure that all the items that you ordered have been supplied and that they are undamaged. If you have any questions regarding optional accessories, or if you wish to place an order, contact the dealer from whom you purchased the instrument.

Optional Spare Parts

Mini-clip convertor B9852CR

Carrying case 700915

BNC adapter B9852CS

Front cover (clear type) 700917

Ground lead B9852CT

50 Ω Through terminator 700976

The following optional spare parts are available. On receiving these optional spare parts, make sure that all the items that you ordered have been supplied and that they are undamaged. If you have any questions regarding optional spare parts, or if you wish to place an order, contact the dealer from whom you purchased the instrument.

Part Name Part No. Minimum Q’ty Remarks

150 MHz probe 700998 1 Input impedance: 10 MΩ, Length: 1.5 m (10:1, 1:1 selectable)

Roll chart B9850NX 5 Thermo-sensible paper, Total length: 30 m Power supply fuse A1351EF 2 Time lag, 3.15 A, 250 V

Note

It is recommended that the packing box be kept in a safe place. The box can be used when you need to transport the instrument somewhere.

IM 701530-01E

Safety Precautions

This instrument is an IEC safety class I instrument (provided with terminal for protective grounding). The following general safety precautions must be observed during all phases of operation, service, and repair of this instrument. If this instrument is used in a manner not specified in this manual, the protection provided by this instrument may be impaired. Also, YOKOGAWA Electric Corporation assumes no liability for the customer’s failure to comply with these requirements.

The following symbols are used on this instrument.

To avoid injury, death of personnel or damage to the instrument, the operator must refer to an explanation in the User’s Manual or Service manual.

Function Grounding Terminal (This terminals shold not be used as a “Protective grounding terminal”.)

Alternating current

ON(power)

OFF(power)

In-position of a bistable push control

Out-position of a bistable push control

IM 701530-01E

Safety Precaustions

WARNING

Power Supply

Ensure the source voltage matches the voltage of the power supply before turning on the power.

Power Cord and Plug

To prevent an electric shock or fire, be sure to use the power supply cord supplied by YOKOGAWA. The main power plug must be plugged in an outlet with protective grounding terminal. Do not invalidate protection by using an extension cord without protective grounding.

Protective Grounding

Make sure to connect the protective grounding to prevent an electric shock before turning on the power.

Necessity of Protective Grounding

Never cut off the internal or external protective grounding wire or disconnect the wiring of protective grounding terminal. Doing so poses a potential shock hazard.

Defect of Protective Grounding and Fuse

Do not operate the instrument when protective grounding or fuse might be defective.

Fuse

To prevent a fire, make sure to use fuses with specified standard (current, voltage, type). Before replacing the fuses, turn off the power and disconnect the power source. Do not use a different fuse or short-circuit the fuse holder.

Do not Operate in an Explosive Atmosphere

Do not operate the instrument in the presence of flammable liquids or vapors. Operation of any electrical instrument in such an environment constitutes a safety hazard.

Do not Remove any Covers

There are some areas with high voltage. Do not remove any cover if the power supply is connected. The cover should be removed by qualified personnel only.

External Connection

To ground securely, connect the protective grounding before connecting to measurement or control unit.

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How to Use this Manual

Structure of the Manual

This User’s Manual consists of 16 chapters, an Appendix and an Index as described below.

Chapter Title Description 1 Functions Describes measurement principles and functions. Although

2 Name and Use of Gives the name of each part and describes how to use it.

Each Part The corresponding reference pages for panel keys and the

3 Before Starting Describes points to watch during use and describes how to

Observation and install the instrument, connect the power cord, turn the Measurement of power switch ON/OFF and connect probes as well as how to Waveforms set the date and time.

4 Common Describes the operations used to make settings, such as

Operations start/stop acquisition, auto set-up and initialization of each

5 Setting the Vertical Describes how to turn channels ON/OFF, how to make

and Horizontal settings, such as input coupling, probe attenuation and Axes vertical sensitivity, that are related to the ver tical axis

6 Activating a Trigger Describes trigger setting operations, such as those for

7 Changing Describes how to make acquisition condition settings, such

Acquisition as acquisition mode, sampling mode, input filter and and Display hysteresis, as well as how to make display condition Conditions settings, such as waveform expansion, interpolation,

8 Analyzing Describes how to measure waveforms using cursors,

Waveforms performautomatic measurement of waveform parameters

9 Performing a Describes how to perform a GO/NO-GO action by setting the

GO/NO-GO Action waveform zone or setting limits for waveform parameters,

10 Outputting Displayed Describes how to output displayed waveforms (screen

Waveforms and hardcopy) and set-up information to the built-in printer or Setting Parameters plotter connected to the GP-IB interface. to the Printer/Plotter

11 Storing and Recalling Describes how to store displayed waveforms or settings in the

Data from the internal memory, ho w to recall stored wa v eform data and display Internal Memory the waveforms, and how to recall settings and change them.

12 Saving and Describes how to save waveform data or set-up data to a

Loading Data floppy disk, how to load saved data, how to initialize a floppy from a Floppy Disk disk and how to delete data.

13 Saving and Describes how to save the waveform data or set-up data to

Loading Data from the SCSI device or the internal hard disk. Describes how to a SCSI Device or load the saved data, initialize the disk, delete the data, and

the Internal Hard Disk other operations. 14 Other Operations Describes operations such as those required for trigger output. 15 Troubleshooting, Describes how to diagnose the cause of trouble and how to

Maintenance and correct it, as well as describing each message that may

Inspection appear on the screen and how to perform a self test. 16 Specifications Describes the specifications.

Appendix

Index Important terms used in this manual with corresponding

this section does not give a description of the operating methods, it will help you to understand the basic operations.

rotary knobs are also given.

setting as well as operations, such as snapshot, clear trace and calibration, that are used frequently during operation.

(voltage axis), as well as how to make settings related to the horizontal axis (time axis).

setting trigger mode, trigger type, trigger source and trigger level, that enable you to determine acquisition timing.

accumulation, X-Y display and graticule.

and waveform math, and how to display the power spectrum obtained by FFT computation.

then detecting whether the input signal waveform is within the specified range (zone or limits).

Shows a menu map, describes the relationship between the time axis, sample rate and record length, and describes the data format which must be specified when waveform data is saved.

reference page numbers are given.

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Conventions Used in this Manual

Unit

k ........... Denotes “1000”. Example: 100kS/s

K ........... Denotes “1024” or “1002”.

• Example of when K indicates “1024” : 640 KB (storage capacity of a floppy disk)

• Example of when K indicates “1002” : 100 KW (record length for acquisition memory)

Used Characters

Alphanumerics enclosed in double quotation marks usually refer to characters and set values that appear on the screen and panel. The SHIFT + xxx key refers to first pressing the SHIFT key (the indicator above the SHIFT key lights), and then pressing the xxx key to obtain another, specified, function.

Symbols Used

The following symbol marks are used in this User's Manual.

To avoid injury or death of personnel, or damage to the instrument, the operator must refer to the User's Manual. In the User's Manual, these symbols appear on the pages to which the operator must refer.

WARNING

CAUTION

Note Provides information that is important for proper operation

Symbol Marks Used for Descriptions of Operations

The following symbol marks are used in Chapters 3 to 14 to distinguish certain feg|ures in descriptions.

Describes precautions that should be observed to prevent the danger of serious injury or death to the user.

Describes precautions that should be observed to prevent the danger of minor or moderate injury to the user, or the damage to the property.

of the instrument.

Relevant Keys Indicates the relevant panel key which are

necessary to carry out the operation.

Operating Procedure Carr y out steps in the order shown. The

operating procedures are given with the assumption that you are not familiar with the operation. Thus, it may not be necessary to carry out all the steps when changing settings.

Keys and Procedure Shows the above mentioned relevant keys and

the operating procedure in one block.

Explanation Describes settings and restrictions relating to the

operation. A detailed description of the function is not provided. For a detailed description of the function, refer to Chapter 1.

IM 701530-01E

Introduction .......................................................................................................................................... 1

Checking the Contents of the Package .............................................................................................. 2

Safety Precautions............................................................................................................................... 5

How to Use this Manual....................................................................................................................... 7

Conventions Used in this Manual....................................................................................................... 8

Chapter 1 Functions

1.1 System Configuration and Block Diagram ............................................................................ 1-1

1.2 Setting the Vertical and Horizontal Axes...............................................................................1-2

1.3 Setting a Trigger.................................................................................................................... 1-8

1.4 Setting the Acquisition and Display Conditions ..................................................................1-12

1.5 Analyzing the Waveform .....................................................................................................1-18

1.6 Other Useful Functions ....................................................................................................... 1-20

Chapter 2 Name and Use of Each Part

2.1 Front Panel / Rear Panel / Top View ..................................................................................... 2-1

2.2 Operation Keys / Rotary Knob .............................................................................................. 2-3

2.3 Display ..................................................................................................................................2-6

Chapter 3 Before Starting Observation and Measurement of Waveforms

3.1 Precautions During Use ....................................................................................................... 3-1

3.2 Installing the Main Unit .........................................................................................................3-2

3.3 Connecting the Power Cord.................................................................................................. 3-3

3.4 Turning the Power Switch ON/OFF....................................................................................... 3-4

3.5 Connecting a Probe ..............................................................................................................3-5

3.6 Compensating the Probe (Phase Correction)....................................................................... 3-6

3.7 Setting the Date and Time ....................................................................................................3-7

Chapter4 Common Operations

4.1 Starting and Stopping Acquisition ........................................................................................4-1

4.2 Displaying Waveforms using the Auto Set-up Function ........................................................ 4-2

4.3 Initializing Settings ................................................................................................................ 4-4

4.4 Halting a Waveform and Erasing the Halted Waveform (Snapshot and Clear Trace) ...........4-5

4.5 Performing Calibration .......................................................................................................... 4-6

4.6 Setting Values....................................................................................................................... 4-7

4.7 Entering Characters using the Keyboard.............................................................................. 4-8

Chapter 5 Setting the Vertical and Horizontal Axes

5.1 Turning Display of Input Signal Waveforms ON/OFF ............................................................ 5-1

5.2 Setting the Input Coupling ....................................................................................................5-2

5.3 Setting the Probe Attenuation............................................................................................... 5-4

5.4 Inverting a Waveform ............................................................................................................ 5-5

5.5 Setting the Vertical Sensitivity .............................................................................................. 5-6

5.6 Changing the Waveform’s Vertical Position........................................................................... 5-7

5.7 Selecting the Timebase ........................................................................................................ 5-8

5.8 Setting the Time Axis..........................................................................................................5-10

5.9 Changing the Waveform’s Horizontal Position....................................................................5-12

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App

Index

Contents

Chapter 6 Activating a Trigger

6.1 Relationship between Trigger Type and Trigger Source/Slope/Level ....................................6-1

6.2 Setting the Edge Trigger .......................................................................................................6-2

6.3 Setting the Window Trigger...................................................................................................6-4

6.4 Setting the TV Trigger ........................................................................................................... 6-5

6.5 Setting the OR Trigger (Optional) ......................................................................................... 6-8

6.6 Setting the Pattern Trigger (Optional) ...................................................................................6-9

6.7 Setting the Width Trigger (Optional).................................................................................... 6-11

6.8 Setting the Trigger Mode..................................................................................................... 6-13

6.9 Setting the Action-On Trigger ............................................................................................. 6-15

6.10 Setting the Trigger Coupling and HF Rejection................................................................... 6-17

6.11 Changing the Trigger Position............................................................................................. 6-18

6.12 Setting the Trigger Delay ....................................................................................................6-19

6.13 Setting the Hold-off Time .................................................................................................... 6-20

Chapter 7 Changing Acquisition and Display Conditions

7.1 Selecting Acquisition Mode, Sampling Mode, and Record Length for DL1540CL................ 7-1

7.2 Setting the Input Filter .......................................................................................................... 7-3

7.3 Zooming the Waveform.........................................................................................................7-4

7.4 Acquiring Waveforms using the Sequential Store Function.................................................. 7-7

7.5 Using the History Memory Function ..................................................................................... 7-9

7.6 Changing the area for displaying the waveform..................................................................7-11

7.7 Changing the Interpolation Settings ................................................................................... 7-12

7.8 Displaying an Accumulated Waveform ............................................................................... 7-13

7.9 Displaying an X-Y Waveform ..............................................................................................7-15

7.10 Changing the Graticule, Scale and % Marker Settings ...................................................... 7-16

7.11 Turning the Waveform Information Display ON/OFF........................................................... 7-17

7.12 Changing the Screen Intensity ........................................................................................... 7-18

Chapter 8 Analyzing Waveforms

8.1 Measuring a V-T Waveform using Cursors ........................................................................... 8-1

8.2 Measuring an X-Y Waveform using Cursors......................................................................... 8-6

8.3 Measuring Waveform Parameters Automatically .................................................................. 8-8

8.4 Using the Linear Scaling Function ...................................................................................... 8-16

8.5 Performing Waveform Math (Addition, Subtraction and Multiplication)...............................8-18

8.6 Displaying the Power Spectrum (Performing FFT Computation) ........................................ 8-20

8.7 Measuring the Power Spectrum using Cursors .................................................................. 8-21

Chapter 9 Performing a GO/NO-GO Action

9.1 Judging using a Waveform Zone .......................................................................................... 9-1

9.2 Judging using Measured Values of Waveform Parameters................................................... 9-8

9.3 Using the GO/NO-GO Signal Output Function ................................................................... 9-13

Chapter 10 Outputting Displayed Waveforms and Setting Parameters to the Printer/Plotter

10.1 Loading a Chart in the Optional Built-in Printer .................................................................. 10-1

10.2 Printing Waveforms and Additional Information using the Optional Built-in Printer ............ 10-3

10.3 Real-time Printing using the Optional Built-in Printer ......................................................... 10-6

10.4 Connecting an External Plotter ........................................................................................... 10-7

10.5 Printing Displayed Waveforms and Additional Information using an External Plotter ......... 10-8

10.6 Entering a Comment ........................................................................................................ 10-10

10.7 Printing the Screen Image to an External Printer ............................................................. 10-11

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Chapter 11 Storing and Recalling Data from the Internal Memory

11.1 Storing and Recalling Displayed Waveforms ...................................................................... 11-1

11.2 Storing and Recalling Setting Parameters.......................................................................... 11-3

Chapter 12 Saving and Loading Data from a Flopply Disk

12.1 Floppy Disks ....................................................................................................................... 12-1

12.2 Formatting a Floppy Disk.................................................................................................... 12-2

12.3 Saving and Loading Waveform Data ..................................................................................12-4

12.4 Saving and Loading Setting Parameters ............................................................................ 12-9

12.5 Saving Screen Image Data............................................................................................... 12-11

12.6 Deleting and Protecting Saved Data ................................................................................ 12-14

Chapter 13 Saving and Loading Data from the SCSI Device or the Internal Hard Disk

13.1 Connecting a SCSI Device ................................................................................................. 13-1

13.2 About the Internal Hard Disk (for /C8 option only).............................................................. 13-2

13.3 Selecting the SCSI Device or the Internal Hard Disk ......................................................... 13-3

13.4 Formatting the Media.......................................................................................................... 13-4

13.5 Saving and Loading Waveform Data ..................................................................................13-6

13.6 Saving and Loading Setting Parameters .......................................................................... 13-11

13.7 Saving Screen Image Data............................................................................................... 13-13

13.8 Deleting and Protecting Saved Data ................................................................................ 13-17

13.9 Changing the SCSI ID Number (on Models with the Internal Hard Disk) .........................13-19

13.10Copying the Data Saved on the Internal Hard Disk (option) to the Floppy Disk ...............13-20

13.11Connecting a PC to the DL1540CL /C8............................................................................ 13-21

Contents

Chapter 14 Other Operations

14.1 Using a Trigger Output Signal.............................................................................................14-1

14.2 Downloading Waveform Data to an AG Arbitrary Waveform Generator ............................. 14-2

14.3 Checking the System Condition ......................................................................................... 14-3

14.4 Adjusting the Printer Density ..............................................................................................14-4

14.5 Using a Video Signal Output (VIDEO OUT) .......................................................................14-5

14.6 Setting the Brightness of the LCD ......................................................................................14-6

Chapter 15 Troubleshooting, Maintenance and Inspection

15.1 Troubleshooting ..................................................................................................................15-1

15.2 Error Messages and Corrective Actions ............................................................................. 15-2

15.3 Self Test.............................................................................................................................. 15-6

15.4 Replacing the Power Supply Fuse...................................................................................... 15-7

15.5 Recommended Parts for Replacement .............................................................................. 15-8

Chapter 16 Specifications

16.1 Input Section....................................................................................................................... 16-1

16.2 Trigger Section....................................................................................................................16-2

16.3 Time Axis ............................................................................................................................16-3

16.4 Display ................................................................................................................................16-3

16.5 Functions ............................................................................................................................ 16-4

16.6 Rear Panel Input/Output Section ........................................................................................16-5

16.7 Communication Interface.................................................................................................... 16-6

16.8 Built-in Printer (optional) ..................................................................................................... 16-7

16.9 Built-in Floppy Disk Drive ................................................................................................... 16-7

16.10Internal Hard Disk (for /C8 option)......................................................................................16-7

16.11General Specifications........................................................................................................ 16-8

16.12External Dimensions ........................................................................................................ 16-10

App

Index

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Contents

Appendix

Index

Appendix 1 Menu Map...............................................................................................................App-1

Appendix 2 Relationship between the Time Axis Setting, Sample Rate and Record Length (for

DL1540C) ..................................................................................................................................App-2

Appendix 3 Relationship between the Time Axis Setting, Sample Rate and Record Length (for

DL1540CL) ................................................................................................................................App-5

Appendix 4 How to Calculate the Area of a Waveform ............................................................App-11

Appendix 5 Output Data Format used when Saving Waveform Data (Example DL1540CL) ..App-12

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Chapter 1 Functions

1.1 System Configuration and Block Diagram

System Configuration

Functions

Block Diagram

CH1

CH2

CH3

CH4

External trigger input/ External clock input

HP-GL plotter

Hard copy Set-up information list

YOKOGAWA AG series arbitrary waveform generator Arbitrary waveform output

Personal computer

Remote control Data analysis

Vertical control circuit

Input coupling

circuit

Data transfer

Pre-

ATT

amplifier

Front end control circuit

External printer Hard copy

Communication

SCSI device Saving / loading data

Multiplex circuit

A/D

Timebase

Trigger circuit

Object to be measured

Data

processing circuit

Acquisition control circuit

Built-in printer

Hard copy Set-up information list

GO/NO-GO judgement output

Trigger output

RGB video signal output

External clock input / trigger input

Signal input

Acquisition memory

Display buffer

Display control

circuit

CPU

Floppy disk

Saving / loading data

Color LCD display

Keyboard

Printer

GP-IB

FDD

Half pitch interface connector (included the output for GO/NO-GO judgement)

Trigger output

(Optional)

IM 701530-01E

Signal Flow

A signal input via the input terminal is sent to the vertical control circuit. The vertical control circuit consists of an input coupling circuit, attenuator (ATT) and preamplifier, and it adjusts the voltage and amplitude of the signal according to the input coupling, probe attenuation, vertical sensitivity and offset voltage settings, before sending the signal to the multiplex circuit. The signal will then be sent to the A/D converter matching settings such as time axis and so on. The A/D converter samples the signal at a sample rate of 100 MS/s to convert it to digital data. The digital data is then stored in the acquisition memory by the data processing circuit at a sample rate which matches the time axis setting. The data sent out from the acquisition memory by the data processing circuit is then processed according to the invert waveform and averaging settings, then subjected to interpolation and P-P compression (to obtain the maximum/minimum values within each specified intervals), then converted into display data by the display control circuit and finally memorized in the wavefor m display buffer. The data read from the waveform display buffer and non-waveform display data read from the graphic display buffer are combined, and the combined image is displayed on the color LCD display.

1-1

1.2 Setting the Vertical and Horizontal Axes

Vertical

control

circuit

Input terminal

Input coupling ≡ page 5-2. ≡

When you only want to observe the amplitude of an alternating current signal, or when you just want to observe the signal relative to a given reference voltage, eliminating the direct current components from the input signal makes observation easier. You may also want to check the ground level or observe the input signal waveform with the offset voltage removed. In this case, you can change the input coupling setting. This will switch the coupling method, which determines how the input signal is input to the vertical control circuit (voltage axis). The input coupling method can be chosen from the following.

The input signal is sent through a capacitor to the attenuator in the vertical control circuit. This method can be used when you just want to observe the amplitude of the alternating current signal, eliminating the DC components from the input signal, or when you want to observe the signal relative to a given reference voltage.

The input signal is sent directly to the attenuator in the vertical control circuit. This method can be used when you want to observe both the DC and AC components of the vertical input signal. This method also enables observation of the input signal with the offset voltage (DC voltage) eliminated. This function is useful when you want to observe ripples in a DC output signal.

Input terminal

Vertical

control

circuit

GND

The ground signal, not the input signal, is connected to the attenuator in the vertical control circuit. This method enables observation of the ground level on the screen.

Probe Attenuation ≡ page 5-4. ≡

A probe is usually used to connect the circuit to be measured to an input terminal. Use of a probe provides the following advantages.

• the voltage and current of the circuit to be measured are not disturbed;

• a signal can be input without distortion;

• the measurement voltage range of the oscilloscope can be widened. A 150 MHz passive probe is supplied with the instrument. The probe attenuates the input signal by 1/10. When a probe is used, the probe attenuation must match the instrument’s attenuation setting so that the input voltage can be measured directly. Set the instrument’s attenuation to 10:1 if the supplied probe is to be used. In addition to 10:1, attenuations of 1:1, 100:1 and 1000:1 are provided. When you use a probe other than the one supplied with the instrument, set the instrument’s attenuation so that it matches the probe’s attenuation.

Input terminal

Vertical

control

circuit

1-2

IM 701530-01E

Inverted Wa veform Display ≡ page 5-5. ≡

1div=1V 1div=500mV

When V/div is switched from 1 V/div to 500 mV/div

The voltage axis is inverted about the ground as shown below, and the wavefor m is displayed. In other words, + voltage is converted to – voltage and – voltage to + voltage.

Original waveform (not inverted)

Ground level

Vertical sensitivity ≡ page 5-6. ≡

The V/div (vertical sensitivity) setting is used to adjust the amplitude of the displayed waveform so that the waveform can be observed easily. The V/div setting is made by setting the voltage value per division on the screen grid. The set-up value for the vertical sensitivity is displayed according to the probe’s attenuation setting. The V/div setting can be either “VAR” or “CAL”. In case of the “CAL” setting, attenuators with different attenuation rates are used to change the ver tical sensitivity, which then changes in steps of 1 V/div → 2 V/div → 5 V/div. In case of the “VAR” setting, fine adjustment of the sensitivity set under the “CAL” setting can be performed. The setting range is approximately 0.4 to 2.5 times the value of the “CAL” setting. Digital data are taken from the “CAL” setting and after calculating they will be displayed at the “VAR” setting. The measurement accuracy of the voltage axis using the “VAR” setting however, is the same as the measurement accuracy set at the “CAL” setting.

1.2 Setting the Vertical and Horizontal Axes

Functions

Inverted waveform

Note

Vertical sensitivity setting and measurement resolution

For accurate voltage measurement, set the V/div so that the maximum amplitude of the displayed waveform is displayed using the full height of the screen (8 divisions). The instrument uses an 8-bit A/D converter to sample the input signal with a resolution of 255 levels. When displaying a waveform, 25 levels are used for each division of the grid. Thus, in normal display mode (not expansion display mode), the full range (255 levels) of the A/D converter is equivalent to 10.24 div. From this, it can be understood that increasing the V/div setting decreases the voltage per div (25 levels), thereby increasing the display (measurement) resolution.

A/D converter

full range:

255 levels

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Display range: 200 levels

25 levels

1-3

1.2 Setting the Vertical and Horizontal Axes

Vertical Position of the Waveform ≡ page 5-7. ≡

Since a total of four input waveforms can be displayed, they may overlap each other, making observation difficult. In this case, the wavefor ms can be moved in the vertical direction so that they can be observed more easily. Furthermore, full scale in the vertical direction is eight divisions of the grid as mentioned earlier, and the voltage display range is eight times the vertical sensitivity setting (voltage value per division). Thus, increasing the vertical sensitivity results in a narrower voltage display range. However, this function allows the ground level (0 V level) to be shifted up and down up to four divisions from the center of the waveform frame, so that observation of waveforms is possible over the entire voltage display range (V/div value x 16 divisions). This is because the input voltage range of the A/D converter shifts due to the change in the frame position. However, when acquisition is stopped and displayed waveforms are not updated, the input voltage range does not shift even if the frame position is moved. As a result, acquisition within a voltage display range exceeding 10.24 divisions (that is, equivalent to the full range of the A/D converter) becomes impossible, thereby resulting in a discontinuous waveform as shown on the right.

Position range

= 16 divisions

Time Axis ≡ pages 5-8 and 5-10. ≡

Selection of the timebase

With the default settings, sampling timing is controlled by the clock signal output from the timebase circuit of the instrument (refer to the Block Diagram, page 1-1). The sampling timing can be controlled by an external clock signal instead of the clock signal from the timebase circuit. For DL1540C/DL1540CL, an external clock signal can be input to the CLOCK IN terminal on the rear panel or to the CH4 input terminal. When an external clock is input to the CLOCK IN terminal, the clock must be of TTL level, however up to four waveforms can be observed at the same time. On the other hand, if an external clock is input to the input terminal, the clock can be of the same signal level normal input signals. This also allows you to check the clock signal waveform before observing the desired waveform. This external clock function is useful when you are observing a signal whose period varies or when you are observing a waveform by synchronizing it with the clock signal to be measured.

CH1

Display area = 8 divisions

A/D

1-4

CH4

EXT CLOCK IN

Internal timebase

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1div=500µs

10div

1div=1ms

501points

0 500

Sampling data

Time axis

Display record length

Record length of

acquisition memory

P-P compression

Voltage axis

1.2 Setting the Vertical and Horizontal Axes

Setting the time axis

When using the internal clock, set the time axis scale as a time duration per division of the grid (T/div). The setting range is 2 ns/div to 50 s/div. The time range in which waveform is displayed is “time axis setting x 10”, as the display range along the horizontal axis is 10 divisions.

Note

Display of time axis direction

The sampled data is read into the acquisition memory, and a waveform is displayed based on this data. The number of data stored into the acquisition memory differs depending on settings such as time axis settings, trigger mode, and acquisition mode. The number of display points in the time axis direction on a 10-div screen is 501 points (i.e. 50 points per division). Thus, the number of displayed points and record length might slightly differ and this will be treated as follows (for more details on the relation between time axis, trigger mode, acquisition mode, record length of acquisition memory and displayed record length, refer to Appendix 2).

• When the record length is too long The data is displayed in the time axis direction after first being compressed per one division. Depending on the time axis settings, there will be times when all data of full record length of the acquisition memory can be displayed, and times when the data can only be displayed partially. The part which does not appear on your screen, can be viewed by moving the horizontal position of the waveform (refer to page 1-7).

• When the record length is too short The missing data will be interpolated (refer to page 1-15). * Record length is expressed in units of words. One word refers to one point of sampled data.

For example, 10 KW means 10020 points. (K represents 1002.)

Functions

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Relationship between the time axis setting, sample rate and record length

If you change the time axis setting, the sample rate and the record length of the acquisition memory changes too. This is because a linear relation exists between “record length of the acquisition memory” and “time required for acquisition of all data x sample rate”. For more detailed information, refer to Appendix 2/Appendix 3.

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1.2 Setting the Vertical and Horizontal Axes

Relationship between time axis setting and sampling mode

The sampling method (sampling mode) for an input signal changes according to the time axis setting as described hereafter. For T/div settings in the range between 5 µs/div and 100 ns/div, it is possible to switch real-time sampling area to repetitive sampling area. But, for DL1540CL, note that the time axis range over which this feature is actually available will vary according to the maximum displayable record length, as shown in Appendix 3.

• “50s/div to 100 ns/div” → Real-time sampling mode When changing the time axis settings, the sample rate will change and sampling can be performed at a sample rate of maximum 200 MS/s (or 100 MS/s when ch. 3 and 4 are also used). The input signal is sampled sequentially, and data is stored in the acquisition memory. In this mode, the waveform can only be displayed correctly at frequencies up to half the sample rate, due to Nyquist’s theorem*. Sample rate is expressed in S/s (number of samples per second). Thus, this mode is suitable for observation of a waveform which fluctuates more slowly than the sample rate.

* If the sample rate is later than the frequency of the input signal, high frequency components

will be lost. In this case, a phenomenon in which high frequency components change to lower frequency components occurs, due to Nyquist’s theorem. This phenomenon is called aliasing.

Aliasing signal Input signal Sampling point

• 50 ns/div to 5 ns/div → Repetitive sampling mode If T/div is set so that the sample rate exceeds 200 MS/s (or 100 MS/s), the sampling mode is switched to the repetitive sampling mode automatically. In this mode, sampling is performed only once for each cycle of a repetitive signal and several cycles are needed to form a waveform. It appears as if the signal is sampled at a sample rate higher than the actual rate. An apparent sample rate of up to 20 GS/s can be used. However, the maximum observable frequency is 150 MHz due to the instrument’s frequency characteristics. With DL1540CL, it is not possible to set T/div if the maximum display record length is 400 KW or more.

There are two repetitive sampling methods: sequential sampling, in which a signal is sampled sequentially at a fixed interval, and random sampling, in which a signal is sampled at random to produce a waveform. This instrument uses a random sampling method which also enables observation of the waveform up to the trigger point.

Time axis setting and roll mode display

If trigger mode (described on page 1-10) is set to auto-mode or auto-level mode, and T/div is set between 50 ms/div and 50 s/div, the display will not be updated by trigger anymore (update mode), but the mode will switch to roll mode when new data is acquired. In roll mode, the oldest data is deleted, and the waveform shifts from right to left on the screen. A waveform can be observed in the same way as it is recorded on a pen recorder. This mode is useful when you are observing a signal which repeats or which fluctuates slowly. This mode is also useful when you want to detect glitches (fast spikes on a waveform) which occur intermittently. With DL1540CL, the time axis range for roll mode varies depending on the maximum display record length. Refer to Appendix 3. * Roll mode is also turned on when trigger mode is switched to single (short/long) mode, but

the displayed waveform stops when a trigger is activated since trigger setting is effective in single (short/ long) mode.

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Displayed range before

moving (+5 div)

Displayed range

after moving to –5 div

Displayed range

after moving to 0 div

Center of the

waveform display

moves to 0 div

Center of the

waveform display

moves to –5 div

Display record length

Record length of acquisition memory

1.2 Setting the Vertical and Horizontal Axes

Horizontal Position of the Waveform ≡ page 5-12 ≡

In case you acquired more data than can be displayed on one (10 div) screen (i.e. the record length* of the acquisition memory is longer than the record length of one screen), then you can view the data by moving the display position in the time axis direction. This might be the case when using the roll mode display or when the trigger mode is set to single long mode (for DL1540C). The displayed waveform can be moved over a span of +/- 5 div from the center of the screen.

* For more details on the relation between record length of acquisition memory and

displayed record length, refer to page 1-5, Appendix 2 and Appendix 3.

Moving the horizontal position

In roll mode, the display position can be moved after data acquisition is stopped. If the instrument is in a mode other than roll mode, the display position can be moved even during data acquisition. The following example shows how the display position is moved in roll mode.

Note

Relationship between the display range on the screen and the display record length, acquisition memory’s record length and trigger position (see page 1-11) is given below.

• Display range on the screen = Acquisition memory’s record length

The entire waveform data saved in the acquisition memory can be displayed without the need for moving the horizontal position of the waveform.

Trigger position

Functions

Displayed range:10 div (Displayed record length)

Record length of

acquisition memory

• Display range on the screen x 2 > Acquisition memory’s record length > Display range on the screen

Waveform datas which are out of the display range on the screen are acquired in the acquisition memory (up to 10 div) located before (on the left of) the trigger position. The part which is out of the display range on the screen can be displayed by adjusting the horizontal position of the waveform as described earlier.

Trigger position

Waveform data exceeding

the screen display range

Record length of

acquisition memory

Displayed range:10 div (Displayed record length)

• Display range on the screen x 2 = Acquisition memory’s record length > Display range on the

screen

When the length of the waveform data acquired in the acquisition memory located before (on the left of) the trigger position exceeds 10 div, waveform data will be acquired in the acquisition memory located after (on the right of) the trigger position. Waveform data of up to 20 div is acquired. The part which is out of the display range on the screen can be displayed by adjusting the horizontal position of the waveform as described earlier.

Trigger position

Displayed range:10 div (Displayed record length)

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10 div

Record length of acquisition memory

1-7

1.3 Setting a Trigger

Trigger level

A trigger is activated at this point if "Rise" ( ) is selected.

Trigger source

WIDTH

trigger is activated

[OUT]

trigger is activated

[IN]

Window

trigger is activated

CENTER

WIDTH

CENTER

Trigger Type / Trigger Source / Trigg er Level ≡ pages 6-1 to 6-11. ≡

Trigger type : Selects the type of trigger. The following types are available as

described below: Edge trigger, TV trigger and window trigger. Furthermore, the OR trigger, pattern trigger and width trigger are available as an option.

Trigger source : Selects the signal for the selected trigger type. Trigger level : Sets the voltage level used to judge trigger conditions such as

trigger slope (rise/fall of a signal) and trigger state (high/low level).

Edge trigger → page 6-2.

The edge trigger is the simplest type of trigger and uses a single trigger source to activate a trigger. A trigger is activated when the trigger source exceeds (rises above) or drops (falls) below the preset trigger level*. In addition to input signals (CH1 to CH4), the external trigger input signal and the commercial power supply signal can be used as a trigger source.

* “A trigger is activated” refers to the condition in which trigger conditions are satisfied and a

waveform is displayed.

Window T rigger → page 6-4.

A certain voltage range (window) is set and a trigger is activated when the trigger source level enters this voltage range (IN) or exits from this voltage range (OUT).

TV Trig ger → page 6-5.

The TV trigger is used when you are observing a video signal, and is compatible with NTSC, PAL and HDTV broadcasting systems.

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1.3 Setting a Trigger

OR T rigger (option) → page 6-8.

Multiple trigger sources are selected, and a trigger is activated when one of the trigger conditions set for each trigger source becomes true. Trigger conditions are established by setting the trigger slope.

When CH1 = , CH2 =

CH1

CH2

Functions

Trigger

TriggerTrigger

Pattern trigger (option) → page 6-9.

Multiple trigger sources are selected, and a trigger is activated when all of the trigger conditions set for each trigger source become true or false. Trigger conditions are established by setting combinations of the state (High or Low) of each trigger source. Furthermore, one of the trigger sources can be used as the clock signal, and triggering is synchronized with this clock signal.

Example: a trigger is activated when CH1:L, CH2:L, CH3:L and CH4:L

CH1

CH2

CH3

CH4

CH1

LH L L L CH2 CH3 CH4

L: Low level, H: High level

HHHHLLLL

HLL

Trigger is activated.

L HLLH

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Width trigger (option) → page 6-11.

If the pulse width of a trigger source is narrower or wider than some specified time, then a trigger is activated accordingly. A trigger can also be activated by a single trigger source.

TW TW TW

Trigger is activated.

TW: Specified pulse width

1-9

Half the amplitude

Trigger level Amplitude

1.3 Setting a Trigger

Trigger Mode ≡ page 6-13. ≡

Conditions for updating displayed waveforms are set. The following six types of trigger mode are available.

Auto-mode

Displayed waveforms are updated each time a trigger is activated within a specified time (approximately 100 ms, referred to as the time-out period) and are updated automatically after each time-out period.

Auto-level mode

Waveforms are displayed in the same way as in Auto-mode if a trigger is activated within the time-out period. If no trigger is activated, the center value of the amplitude of the trigger source (page 1-7) is detected and the trigger level is changed automatically to this center value, then a (edge) trigger is activated to update the displayed waveforms.

Normal mode

Displayed waveforms are updated only when a trigger is activated. Displayed waveforms will not be updated if no trigger is activated.

Single (short) mode

When a trigger is activated, displayed waveforms are updated only once, then acquisition stops. This mode is useful when you are observing a single-shot signal. (Called single-shot mode for DL1540C, and single mode for DL1540CL)

Single long mode

As with the single (short) mode, when a trigger is activated, displayed waveforms are updated only once, then acquisition stops. However, the length of acquired data is longer in this mode (up to 120 K words). This mode is available only with DL1540C.

Single (N) mode

This mode is useful when using the sequential store function (refer to page 1-14). Waveforms are acquired and stored in different memory areas each time a trigger is activated, then acquisition stops, and the waveforms are displayed. Acquisition is performed the specified number of times. Acquired waveforms can be displayed together, or they can be displayed individually. This mode is useful when you want to detect a sudden abnormality in a waveform.

1st acquisition 2nd acquisition Nth acquisition

Action-On T rigger ≡ page 6-15. ≡

The displayed waveform can be output to the optional built-in printer or saved to a floppy disk each time a trigger is activated.

Trigger Coupling ≡ page 6-17. ≡

1-10

Input coupling can also be switched for trigger sources as it is for input signals. Select the type of input coupling which is most suitable for the trigger source signal. The following two types of input coupling are available for trigger source signals.

• DC : The trigger source signal is used as the trigger source without any process.

• AC : The trigger source signal is used as the trigger source after DC the content has been removed from it. A trigger can always be activated if the trigger level is set to 0 V as long as the signal’s amplitude is one division or more.

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HF Rejection ≡ page 6-17. ≡

Input signal

Repetitive period: T

Trigger level

Trigger source signal

Trigger signal restricted by hold-off time "t" (when "Rise" is selected as the trigger slope)

Set HF rejection to ON when you want to remove high frequencies exceeding 15 kHz from the trigger source. This prevents a trigger from being activated unexpectedly due to high frequency noise.

Trigger Position ≡ page 6-18. ≡

The trigger position indicates which position of the waveform in the acquisition memory will actually be displayed on the screen. The trigger position can be moved on the display from the center (0 div) to +/-4 div, which enables observation of the waveform up to the trigger point (the pre-trigger section). You can also set the trigger position in the range of +/-5div in steps of 1/50 div. The trigger point refers to the point at which a trigger is activated. In case the trigger delay (to be explained here after) is set to 0s, the trigger point and the trigger position refer to the same location. Observation of the waveform up to the trigger position is made possible by constantly storing sampled data in the acquisition memory (i.e. removing the oldest data each time new data is acquired), retaining data in the memory and displaying it on the screen each time a trigger is activated.

Trigger position

setting range

1.3 Setting a Trigger

Functions

Pre-trigger range Post-trigger range

0 % 100 %

Trigger Delay ≡ page 6-19. ≡

Normally, the waveform around the trigger point is displayed. However the trigger delay function enables display of a waveform which has been acquired after a specified time (called the delay time) has elapsed following activation of a trigger.

Trigger point

Trigger Hold-off ≡ page 6-20. ≡

The trigger hold-off function temporarily stops detection of the next trigger once a trigger has been activated. For example, when observing a pulse train signal, such as a PCM code, display of the waveform can be synchronized with repetitive cycles; or when using the history memory function, you may want to change the repetitive period, as shown below.

Trigger position

Acquisition memory record length

T (trigger position)

Delay time

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1-11

1.4 Setting the Acquisition and Display Conditions

Acquisition Modes ≡ page 7-1. ≡

When storing sampled data in the acquisition memory, it is possible to perform processing on specified data and display the resultant waveform. The following data processing methods are available.

Normal mode

In this mode, sampled data is stored in the acquisition memory without processing.

Envelope mode

In normal mode and averaging mode, the sample rate (the number of times data is acquired per second in the acquisition memory) drops if T/div is increased (refer to Appendix 2/Appendix 3). In envelope mode, the maximum and minimum values are obtained at each acquisition of the data (sampled at 100 MS/s), then the maximum and minimum values are stored as a pair in the acquisition memory (one pair takes up 2 words of memory). Envelope mode is useful when you want to avoid aliasing (page 1-6), since the sample rate is kept high irrespective of the time axis setting (T/div). Furthermore, envelope mode is also useful when you want to detect glitches (pulsing signals which rise very fast) or display an envelope of a modulating signal.

Averaging mode

Averaging is a process in which waveforms are acquired repeatedly to obtain the average of waveform data of the same timing (the same time in relation to the trigger point). When the trigger mode is not single mode, exponential averaging is performed on the waveform data using the following equation, then the resultant waveform is stored in the acquisition memory and displayed on screen. The attenuation constant can be set between 2 and 256 (in steps of 2

Exponential averaging

An = {(N–1)An–1+Xn}

An Xn N

This averaging process is useful when you want to eliminate random noise.

Sampling Mode ≡ page 7-1. ≡

As explained earlier in “Relationship between the time axis setting and sampling mode” (page 1-6), data sampling can be performed either in real-time or in repetitive sampling mode depending on the T/div setting (for DL1540CL, the T/div and maximum displayable record length). If T/div is set between 50 ns/div and 5 ns/ div, data sampling will be performed in the repetitive sampling mode. (But, for DL1540CL, note that these T/div settings are not available if maximum displayable record length is set to a high value.) And, if T/div is set between 5 µs/div and 100 ns/div, data sampling can be performed both in real-time or repetitive sampling mode and schould be selected beforehand. But, for DL1540CL, the range over which this feature is actually available will again vary according to the maximum displayable record length. For details, refer to Appendix 2/Appendix 3.

1 N

: Value obtained after nth averaging : nth measured value : Attenuation constant

Envelope

1-12

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Voltage Voltage

Time

Input signal

Smoothing data

1.4 Setting the Acquisition and Display Conditions

Record Length (Maximum Displayable Record Length) ≡ page 7-1. ≡ , (for DL1540CL)

The term “record length” refers to the number of data points (per channel) read into acquisition memory. “Displayed record length” refers to the number of these data points that actually appear on the screen. (Note that sampling rate and record length will vary according to the T/div setting; see page 1-5). The term “maximum displayable record length” refers to the maximum number of points that can be displayed on the screen. This value can be selected by the user: the available selections are 1 KW, 10 KW, 100 KW, 400 KW, 1 MW, and 2 MW. In general, the acquisition-memory record length and the displayed record length are equivalent. But if the maximum displayable record length is set to 1 KW, 10 KW, or 100 KW and operation is in roll mode, then the acquisition acquisition -memory record length will be double the maximum displayable record length. As an example: if maximum displayable record length is set to 100 KW and the T/div is 50 ms/div, then the record length within acquisition memory will be 200 KW (200, 400 points). Only 100 KW of this length can appear on the screen at any given time. But the waveform’s horizontal position can be shifted as necessary to enable viewing over the entire 200 KW record (see page 1-7). High record-length settings are useful for monitoring repetitive long-period signals and rapid sustained single-pulse signals. But note that the three highest settings (400 KW, 1 MW, and 2 MW) involve various operational restrictions. For details about these restrictions, refer to Section

7.1. For details of the record length, refer to Appendix 2/Appendix 3.

Functions

Input Filter ≡ page 7-3. ≡

Smoothing

The smoothing function enables the instrument to ignore small fluctuations in rapidly changing waveform data so that the overall characteristic of the data can be understood. The function acts as a low-pass filter. A weighted moving average value is obtained for each set of five points of sampled data, then the result is displayed as a wavefor m. This process is useful when you want to eliminate low levels of noise on input signals. Furthermore, smoothing is performed on the data stored in the acquisition memory, thus it can still be performed after acquisition has stopped, allowing the elimination of noise on single-shot signals.

Bandwidth limit

High frequency noise of 20 MHz or higher can be eliminated from the input signal.

Expanded Wavef orm ≡ page 7-4. ≡

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Waveforms can be expanded in the time axis direction. This function is useful when you want to change the T/div setting after the waveform has been displayed in single mode or when you want to extend the acquisition time to observe a particular part of the waveform thoroughly. As explained in “Display of the time axis direction” on page 1-5, the number of data points stored in the acquisition memory in normal display mode is greater than the number of display points (501 points) stored in the time axis direction. Hence, the displayed waveform is P-P compressed in the time axis direction. In other words, more than one waveform data value is displayed at same individual points.

1-13

expansion (zoom) box

Pre-zoom waveform

expanded waveform

Display example in case N=100 times Displaying all waveforms

(ALL)

Displaying newest waveform (Display Number=0)

Displaying oldest waveform (Display Number=–99)

1.4 Setting the Acquisition and Display Conditions

The zoom function described here reduces the compression ratio so as to enable observation of individual data points from acquisition memory. The maximum selectable magnification rate depends on the displayed record length: 10x zoom at 1 KW length; 100x at 10 KW; 1000x at 100 KW, 5000x at 400 KW; 10,000x at 1 MW; and 25,000x at 2 MW. Specifically, the waveform can be zoomed until the number of displayed samples per division falls to 10 (until the displayed record length for the full screen falls to 100 points). If you zoom in such that the number of points per division is less than 50, an interpolation function will automatically supply interpolation over the time axis direction, as described on the next page. Zoom position is specified in units of grid division.

* Display record length of 400 KW, 1 MW and 2 MW is available on DL1540CL.

Display in zooming mode

As shown below, it is possible to select to display a pre-zoom waveform (MAIN) and its expanded waveform (ZOOM) simultaneously, or to display the expanded waveform only. In the MainZoom display, a box is displayed in the display frame for the pre-zoom waveform to indicate the position of the expanded waveform.

MainZoom display ZOOM display

Sequential Store ≡ page 7-7. ≡

In the real-time sampling mode, waveform data will be stored to the acquisition memory only a set number of times, and all waveforms can be displayed. This stops automatically after acquisition. This function is operable when the trigger mode is set to single(N) mode. The maximum number of waveforms that can be stored into acqsuisition memory under this mode varies according to model and the maximum displayable record length in the range from 5 to 100 waveforms. The acquisitionmemory record length (the number of data points per waveform for a given channel) is equivalent to the maximum displayable record length. Sequential-store operation is not available at maximum displayable record lengths of 400KW or above. Once the specified number of waveforms have been stored, you can display any of the waveforms individually or all of them together, so that it is possible to derive a time series of the wavefor m variation. The drawings below illustrate how stored data can be displayed (assuming sequential storage of 100 waveforms).

1-14

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History Memory ≡ page 7-9. ≡

The oscilloscope automatically retains the last N waveforms recorded by real-time sampling, where N is equivalent to the maximum number of waveforms that can be stored by sequential-store. (The record-length for history storage is the same as that for sequential-store.) The oscilloscope retains all waveforms for the first N triggers; then, for each subsequent trigger, the oscilloscope deletes the oldest stored wavefor m. You are free to switch the display from the current (newest) waveform to any of other N-1 waveforms in the history. The illustration below shows how data can be displayed, assuming N=100.

Saved waveform data of previous 100 triggers

1.4 Setting the Acquisition and Display Conditions

Functions

Current waveform display (Display Number = 0)

Display Number 0

Any former waveform display (display number is selectable in the range –1 to –99)

Display Number –25

Wide Screen ≡ page 7-11. ≡

The area for displaying the waveform can be switched from normal mode at 501 dots (horizontal) X 401 dots (vertical) to wide mode at 601 dots (horizontal) X 401 dots (vertical).

Display Interpolation ≡ page 7-12. ≡

This instrument displays waveforms at 50 dots* per division in both the vertical and horizontal axis directions, as shown below. However, if the dots corresponding to the sampled data are not contiguous, the instrument will interpolate between them. The interpolation method can be selected from the following.

* Dots are also called pixels, and are the smallest units used to construct waveforms and

characters on the screen.

Line interpolation

Interpolates between two dots using a straight line.

Sine interpolation

Generates interpolation data using the function sin(X)/X then interpolates between two dots using resulting sine curve. Sine interpolation is suitable for observation of sine waves.

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1-15

1.4 Setting the Acquisition and Display Conditions

Pulse interpolation

Draws a horizontal line to the time axis position of the next data point, then interpolates between the two dots by drawing a vertical line from the next data point.

No interpolation

Draws only a horizontal line to the time axis position of the next dat point.

Accumulated W aveform Display ≡ page 7-13. ≡

The time that old waveforms remain on the screen is made longer than the waveform update interval so that new waveforms can be accumulated on top of old waveforms. In addition, waveforms can be displayed in different colors depending on the frequency of occurrence of the waveforms. This function is useful when you want to observe jitters and temporary turbulence in waveforms.

X-Y Wavef orm Display ≡ page 7-15. ≡

The horizontal axis (X-axis) is used as the voltage axis for the input signal to CH1 and the vertical axis (Y-axis) is used as the voltage axis for the input signal to CH2 for observing the relationship between the voltages between the two signals. The XY waveforms for CH1 and CH2 can be displayed simultaneously. In addition, they can also be displayed simultaneously with a normal V-T waveform (a waveform displayed using voltage and time axes). Use of this X-Y waveform display function enables measurement of the phase angle between two sine wave signals. For example, two X-Y sine waveforms are displayed to obtain an X-Y waveform (called a Lissajous waveform), from which the phase angle can be obtained.

Phase angle 0°

Phase angle 45°

Phase angle 90°

Frequency

ratio (X:Y)

Lissajous waveform

1:1 1:2 1:3

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1.4 Setting the Acquisition and Display Conditions

Other Display Modes Settings ≡ pages 7-16 to 7-18. ≡

Graticule/scale/% marker

Under the default settings, the graticule (including the grid and frame), scale or % marker is displayed on the display, as shown below, enabling the easy observation of wavefor ms. The type of graticule can be changed and scale display and % marker can be turned ON/OFF.

Graticule: Grid, Scale: ON, % Marker: ON

Graticule: Frame, Scale: OFF, % Marker: OFF

Functions

Intensity

The intensity for items displayed on the LCD display such as characters, graticule and so on can be adjusted. Adjust the intensity according to your needs.

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+ 205 hidden pages