department of oscilloscope engineering guideweb.cecs.pdx.edu/~ecelab/guides/files/oscilloscope -...

OSCILLOSCOPE

GUIDE

Tektronix TDS2000 Series

Department of

Electrical & Computer

Engineering

Tektronix TDS2000 Series Oscilloscope Guide v1.0 Portland State University

1

Contents

1 – INTRODUCTION ....................................................................................................... 2

2 –OSCILLOSCOPE OVERVIEW ................................................................................... 2

3 – INSTRUMENT FRONT PANEL ................................................................................. 3

Power Switch .......................................................................................................................... 3

USB Drive Port ........................................................................................................................ 3

Save Button ............................................................................................................................ 3

Multipurpose Knob ................................................................................................................ 3

LCD Screen ............................................................................................................................. 4

Menu Option Buttons ............................................................................................................ 4

VERTICAL Controls .................................................................................................................. 5

HORIZONTAL Controls ............................................................................................................ 7

TRIGGER Controls ................................................................................................................... 8

Setup and Control Buttons ..................................................................................................... 9

Input Connectors .................................................................................................................. 14

4 – PASSIVE PROBES ................................................................................................. 15

5 – SIMPLIFIED MEASUREMENT PROCEDURE ........................................................ 18

6 – SAVING WAVEFORMS TO A USB DRIVE ............................................................. 19

7 – SAVING WAVEFORMS TO A COMPUTER ........................................................... 21

APPENDIX 1 – SPECIFICATIONS ............................................................................... 23

APPENDIX 2 – REFERENCES ..................................................................................... 24


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1 – Introduction

This guide provides basic instructions for operating the Tektronix TDS2000 Series Digital Phosphor

Oscilloscopes. These are some features of various models1 in the product line:

• 50 to 200 MHz bandwidth

• Up to 2 GS/s sample rate

• 2 or 4 channels

• Full color LCD with graphical user interface

• USB I/O for data transfer and control

• Built-in automated measurements

2 –Oscilloscope Overview

An oscilloscope is an instrument that measures a voltage signal and displays a graph of how the signal

varies over time. The vertical axis of the graph is the voltage, while the horizontal axis is time. Important

signal characteristics can be extracted from the graph, such as the shape and amplitude of the signal,

the frequency or period of a repetitive waveform, and the amount of noise or distortion.

A probe is used to connect the circuit being tested to the inputs of the oscilloscope. Each input, or

channel, can independently measure a signal. In a digital oscilloscope, an analog-to-digital converter

samples the input voltage signal and converts the analog values to digital form. The sampling is

performed repeatedly as part of the time sweep. The scope processes the incoming data and displays it

on the built-in monitor screen as a continuously updated graph of voltage versus time.

Important specifications of a digital oscilloscope include:

• Bandwidth – Specifies the highest signal frequency that can be accurately measured

• Sample rate – Determines how often the input signal can be sampled (samples per second)

• Number of channels – Determines how many independent signals can be measured simultaneously

The front panel of a typical digital oscilloscope has these control sections:

• Vertical – Adjusts the vertical (voltage) scaling and positioning of the waveform

• Horizontal – Controls the horizontal (time) scaling and positioning of the waveform

• Trigger – Provides a way to stabilize the display of repetitive signals on the screen

• Acquisition – Controls how the input signal is acquired or sampled

1 The TDS2014C model has a 100 MHz bandwidth, 2 GS/s sampling rate, and four analog input channels.

Copyright © Tektronix, Inc.


3

3 – Instrument Front Panel

Figure 1: Tektronix TDS2000C series front panel - Copyright © Tektronix, Inc.

Power Switch

The switch located on top of the oscilloscope’s chassis turns the instrument either on or off.

Note: When the power is first applied, the oscilloscope performs a diagnostics test that lasts up to 30

seconds. When the test is done, an on-screen prompt asks if the current date or time needs to

be changed. To exit this display, simply push any button or wait for it to time out.

USB Drive Port

This port is used to attach an external mass storage device. Screen images and waveform data can be

saved to or recalled from a USB flash drive (up to 64 GB in size) that is inserted in the port.

Save Button

Pushing this button saves the waveform. Depending on how the button is configured, the waveform can

either be stored as a file on a USB drive or sent to an attached printer.

Multipurpose Knob

The multipurpose knob is used to navigate the screen, select an item, or change a setting.

Power switch

(on top of chassis)

USB drive

port

Multi-

purpose

knob

Probe input

connectors

Option

buttons

LCD

screen

VERTICAL

controls

HORIZONTAL

controls

TRIGGER

controls

Save/Print

button Various setup

& control buttons


4

LCD Screen

The screen shows a graph of the signal that is measured on an input channel. The oscilloscope provides

controls for making individual channels either active (waveform is displayed on the screen) or inactive

(waveform is omitted).

Each channel is color coded: CH1=yellow, CH2=blue, CH3=purple, CH4=green

The main graph area is divided into a grid to aid in reading the amplitude and timing of the waveforms.

Dotted grid lines represent the major divisions on each axis. The vertical axis has units of voltage, while

the horizontal axis has units of time.

Menu Option Buttons

The TDS2000C series support an on-screen menu for accessing various oscilloscope features that are not

assigned to a dedicated button.

If an oscilloscope function provides menu options, they are displayed in a column on the right side of the

LCD screen. The content of the menu will vary depending on the current function.

To the right of the menu column are the physical option buttons, which are located on the plastic bezel

that surrounds the LCD. By pressing a button, the menu option associated with the button is selected.

Menu

options

Waveform Graticle

divisions

Ground

reference

marker

Channel

indicator

Vertical scale

(voltage/div)

Trigger

values

Trigger

status

Aquisition

mode

Horizontal scale

(time/div)

(VERTICAL)

Voltage

Time (HORIZONTAL)

Waveform


5

VERTICAL Controls

The vertical section adjusts the vertical (voltage) configuration, scaling, and positioning of the waveform.

Each channel has its own independent vertical controls and settings.

1, 2, 3, 4 buttons

The 1 (yellow), 2 (blue), 3 (purple), 4 (green) buttons display on-screen menu options for a selected

channel (CH1 thru CH4). The menu options are applied only to the currently selected channel.

If a channel is not active when its button is pressed, then the channel becomes active, its measured

waveform is displayed on the screen, and its menu options appear.

If a channel is already active when its button is pressed, then the channel becomes inactive, and its

waveform stops being displayed.

The menu options are:

Coupling Selects the channel’s input coupling. DC, AC, Ground

DC Allows both AC and DC signals to get through.

AC Filters out any DC signals, so only the AC variation is displayed.

Ground Temporarily replaces the waveform with a 0 V flat reference line.

BW Limit Limits the bandwidth to filter out high frequency noise. Off, 20 MHz

Volts/Div Selects the resolution of the vertical Scale knob. Coarse, Fine

Probe Sets the scope to match the probe’s operating characteristics. Type, Attenuation

Type Type of probe being used (either voltage or current).

Attenuation Sets the attenuation factor to match the probe’s factor. Press the

option button repeatedly or else use the multipurpose knob.

1X, 10X, 20X, 50X, 100X, 200X, 500X, 1000X

Invert Flips the vertical polarity of the waveform.


6

Math button

The Math (red) button allows math operations to be performed on waveforms. The result is

displayed as a separate red-colored waveform on the screen.


Operation Selects the math operation. +, -, x, FFT

+ Adds two waveforms

- Subtracts two waveforms

x Multiplies two waveforms

FFT Fast Fourier Transform (magnitude vs frequency) of a single waveform

Sources Selects source channels. +,-,x: CH1&CH2 or CH3&CH4 FFT: CH1 thru CH4

Position knob (vertical)

This knob moves the currently selected waveform up or down on the screen. It does not affect the

waveform’s vertical size. When multiple channels are active, the knob is useful for providing some

vertical separation among the waveforms, which are otherwise overlaid by default.

Scale knob (vertical)

This knob adjusts the vertical scale (size) of the currently selected waveform. The vertical voltage

scale is specified in units of volts per division (V/div).

Example: If the scale is 2 V/div, then each major division on the vertical axis represents a 2 V span.


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HORIZONTAL Controls

The horizontal section adjusts the horizontal (time) scaling and positioning of the waveform. All

channels share the same horizontal settings.

Position knob (horizontal)

This knob moves all waveforms left or right on the screen. It does not affect the horizontal time

scale.

Set to Zero button

If waveforms have been horizontally shifted, this sets their position back to the zero reference point.

Scale knob (horizontal)

This knob adjusts the horizontal scale of all waveforms. The horizontal time scale is specified in units

of time per division (e.g., ms/div).

Example: If the scale is 5 ms/div, then each major division on the horizontal axis represents 5 ms.

Horiz button

The button displays on-screen menu options for viewing a waveform across

the entire acquisition period, or just a windowed section of it.


Main Displays the original, complete waveform.

Window Zone Sets the position of the window within the waveform. Use

the horizontal Position knob to move the window’s left (start)

and right (stop) markers to frame the zone boundaries.

Window Displays only the part of the waveform that is within the

defined window zone. The contents of the window are

zoomed out to the full width of the screen.


8

TRIGGER Controls

To show a stable image of a repeating waveform on the screen, the oscilloscope needs to acquire the

signal at the same point on the waveform during each sweep. This is done by setting a threshold voltage

value that, when the measured signal crosses the threshold, causes the oscilloscope to initiate an

acquisition sweep. This threshold is called the “trigger level”. The trigger source can be either the input

signal itself or an external trigger signal.

Note: If the measured input signal never crosses the threshold because the level was set too high or too

low, the displayed waveform will be unstable and jitter erratically on the screen.

Trig View button

As long as this button is pushed, a horizontal dashed line that represents the current trigger level is

superimposed on the trigger source’s waveform.

Force Trig button

Manually initiates acquisition regardless of an adequate trigger signal.

Set to 50% button

Automatically sets the trigger level to the midpoint between the trigger source’s minimum and

maximum voltage values.

Level knob

Manually adjusts the trigger level. An arrow marker on the right edge of the screen shows the level

relative to the waveform.

Trig Menu button

This is used to configure the trigger parameters.


Type Selects the type of trigger to detect. Edge, Video, Pulse

Edge Triggers on the rising/falling edge of a signal that crosses the trigger level.

Pulse Used when the trigger is a very fast pulse that the Edge mode would miss.

Source Selects the trigger signal source. CH1, CH2, CH3, CH4, Ext, Ext/5, AC Line

CH1 … CH4 Uses one of the measurement channels as the trigger source.

Ext An external trigger input is used as the source.

Slope Determines whether to trigger on the rising or falling edge of a signal. Rising, Falling

Mode Determines acquisition method if a valid trigger signal is not available. Auto, Normal

Coupling Sets which components of the trigger signal are passed on to the trigger circuit.

DC, Noise Reject, HF Reject, LF Reject, AC


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Setup and Control Buttons

Buttons in this area provide additional control over waveform acquisition, measurement, and display.

AUTOSET button

Automatically adjusts the VERTICAL, HORIZONTAL, and TRIGGER controls to acquire a usable display.

The controls may need further manual adjustment for best results.

Single button

Enables a single sweep acquisition of a signal, after which the acquisition stops.

Run/Stop button

Allows the user to start and stop a continuous waveform acquisition.

Help button

This accesses the oscilloscope’s built-in help system. Show Topic, Index, Help on Help, Back, Exit

Default Setup button

Sets the oscilloscope back to its initial startup settings.

Acquire button

This sets up the acquisition parameters.

Menu options are:

Sample Default mode for acquiring most waveforms.

Peak Detect Used for detecting glitches and reducing the chance of aliasing.

Average Used for reducing random or uncorrelated noise in the signal display.

Averages (X) Sets the number of averages to use if the Average option is active. 4, 16, 62, 128


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AutoRange button

This sets up automatic scaling of a waveform when it is displayed on the screen.

Menu options are:

Autoranging Determines if the acquired waveform is scaled to fit the screen. On, Off

Vertical and Horizontal Autoranges both the vertical and horizontal scales.

Vertical Only Autoranges just the vertical (voltage) scale.

Horizontal Only Autoranges just the horizontal (time) scale.

Undo Autoranging Undos the last autorange.

Cursor button

This is used to superimpose a pair of movable vertical or horizontal bars on the screen to mark key

points on waveforms for measurement. The oscilloscope provides readouts of the cursors’ absolute

location values at the marked points, as well as relative deltas.

Menu options include:

Type Sets the type of cursor to show (horizontal bars for amplitude, vertical bars for time).

Off, Amplitude, Time

Source Selects which channel’s waveform the cursors will bound.

CH1, CH2, CH3, CH4, MATH, …

Cursor1 If selected, use the multipurpose knob to move cursor bar 1 (vertically when

Type=Amplitude or horizontally when Type=Time).

Cursor2 If selected, use the multipurpose knob to move cursor bar 2 (vertically when

Type=Amplitude or horizontally when Type=Time).

When activated, Cursor 1 and Cursor 2 display continuously updated readouts of their current

values (Amplitude mode: V, Time mode: t, V).

The center slot in the menu list shows a continuous readout of the difference between the two

cursors bars (Amplitude mode: ∆V, Time mode: ∆t, 1/∆t, ∆V).

Display button

The button is used to configure advanced display modes.

Menu options are:

Type Controls how the waveform’s points are displayed. Vectors, Dots

Persistence Sets the length of time each sample point remains displayed.

Off, 1 sec, 2 sec, 5 sec, Infinite

Format Determines the type of data displayed on each display axis. YT, XY

YT Vertical axis is voltage and horizontal axis is time (default mode).

XY CH1 determines the X coordinate (horizontal), while CH1 determines the Y

coordinate (vertical).


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Measure button

This controls access to the oscilloscope’s built-in automated measurements, such as calculating the

amplitude or frequency of a cyclic signal.

The menu slots on the right side of the screen can show up to five measurements simultaneously.

Each slot is labeled with the channel number, measurement type, and updated measured value.

By selecting a slot, these menu options appear to configure the measurement for that slot:

Source Determines which channel will be measured. CH1, CH2, CH3, CH4, Math

Type Type of measurement to be performed.

None, Freq, Period, Mean, Pk-Pk, Cyc RMS, RMS, Min, Max, Cursor RMS, Rise Time, Fall

Time, Pos Width, Neg Width, Duty Cyc, Phase, Delay

None Turns off automated measurement for the source channel

Freq Frequency of the waveform

Period Period (time) of the waveform’s first complete cycle

Mean Arithmetic mean amplitude over the entire record

Pk-Pk Absolute difference between the maximum and minimum peaks of the

entire waveform

Cyc RMS True RMS (root mean square) of the waveform’s first complete cycle

RMS True RMS for all 2500 samples from one frame of the waveform data

Cursor RMS True RMS of the waveform data from the selected starting to ending points

Min Minimum value of the entire 2500 point waveform record

Max Maximum value of the entire 2500 point waveform record

Rise Time Time between 10% and 90% of the first rising edge of the waveform

Fall Time Time between 90% and 10% of the first falling edge of the waveform

Pos Width Time between first rising edge and next falling edge at waveform 50% level

Neg Width Time between first falling edge and next rising edge at waveform 50% level

Duty Cyc Ratio of positive pulse duration to the whole cycle

Phase Phase angle difference from two different channels, using the rising edge of

the first signal compared to the rising edge of the second signal

Delay Time difference from two different channels using the rising edge of the first

signal compared to the rising edge of the second signal

Ref button

This button recalls a waveform that was previously saved to the onboard reference memory and

displays it on the screen. It can then be compared to a waveform that is currently being measured.

Menu options include:

Ref A Recall reference waveform A. Off, On

Ref B Recall reference waveform B. Off, On

Ref C Recall reference waveform C. Off, On

Ref D Recall reference waveform D. Off, On


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Save/Recall button

This controls settings for saving and recalling screen images, waveform data, and setups.

Menu options2 are:

Action Determines which save or recall function is active.

Save All, Save Image, Save Setup, Save Waveform, Recall Setup, Recall Waveform

Save All Configures the Save/Print button.

PRINT Button Determines what the Save/Print button will do.

Saves All To Files, Saves Images To File, Prints

Select Folder Selects the directory on the USB drive for saving files.

Change Folder, New Folder

Save Image Saves the screen image.

File Format Selects the format for saving screen images.

JPEG, PCX, RLE, TIFF, BMP, EPSIMAGE

Select Folder Selects the directory on the USB drive for saving files.

Change Folder, New Folder

Save … Initiates saving the current screen image to a file.

Save Setup Saves the current oscilloscope settings to a file named TEKnnnn.SET on

a USB flash drive or to non-volatile setup memory. …

Save Waveform Saves the current waveform in CSV text format to a file named

TEKnnnn.CSV on a USB drive or to reference memory.

Save To Selects the format for saving screen images.

Ref, File

Source Selects the directory on the USB drive for saving files.

CH1, CH2, CH3, CH4, Math

To Selects the directory on the USB drive for saving files.

RefA, RefB, RefC, RefD

Save Initiates saving the current waveform.

Recall Setup Recalls previously saved oscilloscope settings either from a USB drive or

from non-volatile setup memory. …

Recall Waveform Recalls a previously saved waveform either from a USB drive or from

reference memory. …

2 The lesser-used functions will not be described in depth. Refer to the Tektronix reference manual for details.


13

Utility button

This button gives access to system utility functions.

Menu options3 include:

Limit Test Sets up limit testing of waveforms compared to a template. …

Data logging Sets up logging of data over a long time span. ...

System Status Displays the current setup configuration of the oscilloscope.

Horizontal, Vertical CH1 CH2, Vertical CH3 CH4, Trigger, Misc

Options Configures miscellaneous system options.

Read USB Port, Printer Setup, GPIB Setup, Set Date and Time, Error Log

Rear USB Port Sets the type of device connected to the rear USB port.

Autodetect, Printer, Computer

Printer setup Configures the Save/Print button.

PRINT Button, Ink Saver, Layout, File Format

PRINT Button Determines what the Save/Print button will do.

Saves All To Files, Saves Image To File, Prints

Ink Saver Determines if saved screen images will have a

dark or light background color.

Off, On

Layout Sets the orientation when saving screen images.

Portrait, Landscape

File Format Sets the file type when saving screen images.

JPEG, PCX, RLE, TIFF, BMP, EPSIMAGE

GPIB Setup Sets the address of the oscilloscope for GPIB data connection.

Address

Set Date and Time Sets the oscilloscope’s internal clock. …

Error Log Displays a list of errors logged. …

Do Self Cal Performs a self-calibration routine, which can take several minutes to complete.

OK, Cancel

File Utilities If a FAT32-formatted USB flash drive is inserted in the oscilloscope’s front USB port,

this option gives access to basic file and directory operations on the drive.

Change Folder, New Folder, Delete, Rename, Format

Language Sets the language used for prompts and help menus.

English, French, German, Italian, Spanish, Portuguese, Japanese, Korean, Chinese

3 The lesser-used functions will not be described in depth. Refer to the Tektronix reference manual for details.


14

Input Connectors

External probes are attached to the input connectors on the front panel of the oscilloscope.

1, 2, 3, 4 connector

Each channel has a dedicated female BNC connector. The input resistance is 1 MΩ and the input

capacitance is 20 pF.

Warning

The maximum allowed input voltage is 300 V. Do not exceed this limit!

Ext Trig connector

This female BNC connector is utilized when an external signal is required to trigger the waveform

acquisition. For example, a trigger signal can be either a single pulse or a periodic pulse train.


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4 – Passive Probes

A typical passive probe consists of a cable with a male BNC connector on one end and a retractable hook

tip (or a pointed tip) with ground clip on the other. The BNC side attaches to one of the oscilloscope’s

inputs, while the probe tip is attached to a measurement point in the test circuit.

The probe tip is where the voltage signal enters the probe and is then carried through the cable to the

center pin of the BNC connector. The ground clip provides the ground reference from the test circuit to

the outer shield of the BNC connector.

Figure 2: General purpose voltage probe with accessories – Copyright © Tektronix, Inc.

Figure 3: Simplified circuit model of a 10X probe connected to an oscilloscope’s input channel

(For a 1X probe, Rprobe and Cprobe are omitted and replaced by a direct wire path.)

Retractable Hook

Tip Adapter

Adjustment

Tool

Clip-on Ground

Lead

This end

attaches to the

oscilloscope

input

Cable

Probe

Circuit

Being

Measured

Probe Cable Oscilloscope

Input

Rin 1 MΩ

Cin 20 pF

Rprobe 9 MΩ

Cprobe Ccable

TDS2000 series scopes

have a fixed input

resistance of 1 MΩ. Input

All cables have some

amount of shunt

capacitance. Input

A 10X probe uses a 9 MΩ series

resistor to increase the total

input resistance “seen” by the

measured device to 10 MΩ.

Tip

GND


16

These are some important characteristics of a probe:

• Bandwidth – This is the highest frequency signal that the probe can accurately pass through to the

oscilloscope for measurement. A common metric is the frequency at which the measured signal

amplitude has decreased by 3 dB from the original value.

• Attenuation – The attenuation factor determines how much the probe reduces the amplitude of the

input signal before it enters the oscilloscope. Typical probes are either 1X (no attenuation at all) or

10X (amplitude is divided by 10). Some probes support manual switching between 1X and 10X

modes. Attenuation also affects the total input resistance that is “seen” by the circuit being tested.

Note: The attenuation factor setting in the vertical section of the oscilloscope should be changed to

match the attenuation factor of the probe. The displayed V/div value will be incorrect if the

factors do not match.

• Loading Effect – As seen in the schematic diagram, the probe and oscilloscope are attached in

parallel with the test circuit. As a consequence, the measured voltage is influenced not only by the

circuit’s intrinsic characteristics, but also by the components of the probe and oscilloscope. In

particular, the effective input resistance and capacitance of the combined probe and oscilloscope

system affects the accuracy and fidelity of the voltage measurement.

Table 1: Typical characteristics of common probes

Probe

Description

Attenuation

Ratio

Total Input

Resistance

Total Input

Capacitance

Best Used For

10X probe 10:1 10 MΩ 1 to 25 pF Low-to-high amplitude

DC-to-high frequency

1X probe 1:1 1 MΩ 100 to 200 pF Very low-to-medium amplitude

DC-to-low frequency

For most measurements, the 10X probe is utilized because its high effective input resistance lessens

the load effect on the test circuit, and its low input capacitance allows higher frequencies to be

measured. On the other hand, the large attenuation factor makes measurements of very low

amplitude signals less accurate.

If the voltage level of the input signal is tiny, then a 1X probe may be a better choice because there

is no attenuation through the probe. However, the 1 MΩ input resistance imposes a larger loading

effect and the high input capacitance limits the frequency range.


17

Probe Compensation

Some probes have a built-in compensation network that can be adjusted to better match a probe’s

unique operating characteristics to the oscilloscope’s inputs. Use the following procedure to

compensate a probe:

1. Connect the probe to the desired input channel on the oscilloscope.

2. On the front panel of the oscilloscope, attach the probe’s tip to the Probe Comp terminal and the

probe’s ground lead to the chassis ground terminal. On the TDS2000 series, the terminals are

located by the Channel 1 input connector. PROBE COMP generates a 5 volt square wave at 1 kHz.

3. Push the AUTOSET button to acquire the test signal.

4. Use the probe’s adjustment tool to make the square wave have a flat top.

Figure 4: Effects of probe compensation on a square wave

Under compensated Over compensated Properly compensated


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5 – Simplified Measurement Procedure

1. Before making any connections, verify that the test circuit will not produce voltage or current levels

that could damage the oscilloscope.

2. Turn on the oscilloscope. The instrument is more accurate if allowed to warm up for a while.

3. Choose probes that are appropriate for the measurement. Each channel requires a separate probe.

4. For each channel that will be used:

a. Attach the probe’s BNC connector to an input connector on the oscilloscope.

b. If necessary, configure the coupling and attenuation factor for the channel.

c. If the probe has a built-in compensation network, then compensate the probe.

(Perform compensation whenever a probe is connected to the oscilloscope for the first

time.)

d. Connect the probe to the test circuit. If you will be working with static-sensitive parts, then

wear a grounding strap before making the connections.

i. Attach the ground clip of the probe to a ground point in the circuit.

ii. Attach the probe tip to the voltage measurement point in the circuit.

5. If the test circuit is not turned on yet, then apply power to the circuit.

6. Adjust the oscilloscope’s controls to achieve a stable display of the waveform.

(The Autoset button can be used to get a reasonable initial display.)

7. Voltage measurements are done by counting the number of graticle divisions that a waveform spans

in the vertical direction. Timing measurements are performed similarly in the horizontal direction.

(The Measure button can be used to automate common signal measurements.)


19

6 – Saving Waveforms to a USB Drive

Pressing the Save/Print button on the front panel of the oscilloscope can quickly save a measured

waveform to an attached USB drive. Depending on how the button is configured, it can store the data in

the following formats:

• Screen image

A screen image is an exact copy of what is currently being shown on the LCD screen, including the

annotations around the perimeter of the graph and the menu options. Be sure to adjust everything

to your liking before saving. A captured screen image can be pasted directly into reports.

• CSV file

A CSV file is just a text file with the data stored in Comma Separated Values format:

o Column 1: Defines labels for selected measurement setup parameters

o Column 2: Holds actual values of the parameters at the time of the screen capture

o Column 3: Empty

o Column 4: Holds the time axis (horizontal) values

o Column 5: Holds the voltage axis (vertical) values

The file can be imported into applications like Excel or MATLAB for further analysis.

Option 1: Configuring the Save/Print Button to save only screen images

1. Press: Utility button → Options → Printer Setup

2. Select PRINT Button multiple times until “Saves Image To File” appears.

3. Select File Format multiple times until the desired image type (e.g., JPEG) appears.

OPTIONAL:

4. Select Ink Saver and choose “On” to invert the saved image’s background from its normal black to

white, or choose “Off” to keep the background black.

5. Select Layout and choose either “Portrait” or “Landscape” orientation.

Option 2: Configuring the Save/Print Button to save both screen images and CSV data

1. Press: Utility button → Options → Printer Setup

2. Press: PRINT Button multiple times until “Saves All to Files” is selected.

3. Select the desired File Format, Ink Saver, and Layout settings (see previous section).


20

Using the Save/Print Button to save waveforms

1. Insert a formatted USB drive into the oscilloscope’s front USB port.

2. Adjust the oscilloscope to get a good waveform displayed on the screen.

3. Press the Save/Print button to save the waveform to the USB drive.

Note: After a few seconds, a “clock” icon will appear on the screen. It will then take several more

seconds before the data is finally saved and the normal menu options reappear.

Warning: Wait until the clock disappears before removing the USB drive.

→ If the Save/Print button is configured to save only screen images

A file named TEKnnnn.xxx is created on the USB drive each time the Save/Print button is pressed. nnnn

is a number from 0000 to 9999. It starts at 0000 and is automatically incremented. xxx is the extension

of the image format, e.g., JPG.

→ If the Save/Print button is configured to save both screen images and CSV data

A directory named ALLnnnn is created on the USB drive each time the Save/Print button is pressed.

nnnn is a number from 0000 to 9999. It starts at 0000 and is automatically incremented.

These files are stored within the ALLxxxx directory:

• FnnnnCHm.CSV (m is the channel number)

This is the CSV file containing the raw measured data. Each active channel is stored in its own file.

• FnnnnTEK.xxx (xxx is the extension of the image format, e.g., JPG)

This is the actual screen image file.

• FnnnnTEK.SET

This contains some additional oscilloscope settings.


21

7 – Saving Waveforms to a Computer

Although the TDS2000 series of oscilloscopes can save data to a USB drive, it also supports data transfer

to a computer over a USB cable. Tektronix makes software called OpenChoice Desktop that runs on a

Windows-based computer to control the oscilloscope and initiate screen image and/or data capture.

Starting OpenChoice Desktop

1. Verify that OpenChoice Desktop has been installed on the computer, along with the TekVISA driver.

2. Connect one end of a standard A/B USB cable to the USB port on back of the oscilloscope and the

other end to an available USB port on the computer4.

3. Turn on the oscilloscope and let it fully initialize before running OpenChoice Desktop.

4. Run the OpenChoice Desktop software.

The application window (Figure 6) presents an interface with tabs on top, command buttons on the left,

and the screen image/data area on the right. The default tab is “Screen Capture”.

Figure 6: OpenChoice Desktop startup window

The upper left area of the window should display the name of the connected instrument that will

generate the screen image or waveform data.

Note: If the desired instrument name (e.g., TDS 2014C) is not shown, then follow this procedure:

1. In the main application window, click the [Select Instrument] button.

2. When the Select Instrument pop-up dialog (Figure 5) appears, look for an entry that starts with

“USB0::”. Select that item and click the OK button.

4 The computer communicates with the oscilloscope using the USBTMC-GPIB protocol and SCPI commands.

Figure 5: Pop-up for selecting instrument


22

Using OpenChoice Desktop to get a screen image

1. Click the “Screen Capture” tab.

2. Click the [Get Screen] button to initiate the screen image transfer to the computer.

3. Click [Save As] to save the screen image as a file (jpg, png, bmp, or tif) on the computer’s local drive.

Figure 7: Screen image capture

Using OpenChoice Desktop to get waveform data

1. Click the “Waveform Data Capture” tab.

2. Click the [Select Channels] button.

3. When the Select Channels pop-up dialog (Figure 8) appears, select the channels you want and click

the dialog box’s Get Data button to initiate the data transfer to the computer.

Note: To capture another waveform, click the [Get Data] button on the main application window.

4. Click [Save As] to save the waveform as a file (CSV or tab-delimited text) on the computer’s drive.

Figure 9: Waveform data capture Figure 8: Pop-up for selecting channels


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Appendix 1 – Specifications

Table 2: Manufacturer’s instrument specifications

Model TDS2014C

Bandwidth 100 MHz

Channels 4

Sample rate on each channel 2 GS/s

VERTICAL SYSTEM

Record length 2.5K points

Vertical resolution 8 bits

Vertical sensitivity 2 mV to 5 V/div

DC vertical accuracy ±3%

Maximum input voltage 300 VRMS CAT II; derated at 20 dB/decade above 100 kHz

to 13 Vp-pAC at 3 MHz

Position range 2 mV to 200 mV/div +2 V;

>200 mV to 5 V/div +50 V

Bandwidth limit 20 MHz

Input impedance 1 MΩ in parallel with 20 pF

Input coupling AC, DC, GND

HORIZONTAL SYSTEM

Time base accuracy 50 ppm

TRIGGER SYSTEM

Trigger modes Auto, Normal, Single Sequence

Trigger types Edge (rising/falling), Video, Pulse width

Trigger source CH1, Ch2, CH3, CH4, Ext, Ext/5, AC line

ACQUISITION SYSTEM

Acquisition modes Peak detect, Sample, Average, Single sequence, Roll

mode

WAVEFORM MEASUREMENTS

Automatic measurements

Period, Frequency, +Width, -Width, Rise Time, Fall Time,

Max, Min, Peak-to-Peak, Mean, RMS, Cycle RMS, Cursor

RMS, Duty Cycle, Phase, Delay

Cursors Types: Amplitude and time

Measurements: ∆T, 1/∆T, ∆V

WAVEFORM MATH

Operators Add, Subtract, Multiply, FFT

Sources CH1-CH2, CH2-CH1, CH3-CH4, CH4-CH3,

CH1+CH2,CH3+CH4, CH1×CH2, CH3×CH4

FFT Windows: Hanning, Flat Top, Rectangular

2048 sample points

Autoset menu Single-button, automatic setup of all channels for

vertical, horizontal, and trigger systems


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Appendix 2 – References

[1] Tektronix TDS2000C Series Data Sheet, Tektronix, Inc.

[2] TDS2000C and TDS1000C-EDU Series Digital Storage Oscilloscope User Manual , Tektronix, Inc.

[3] XYZs of Oscilloscopes - Primer, Tektronix, Inc.

[4] ABCs of Probes - Primer, Tektronix, Inc.

department of oscilloscope engineering guideweb.cecs.pdx.edu/~ecelab/guides/files/oscilloscope -...

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