SIGLENT SDS2000 Series User manual

Quick Start
SDS2000 Series
Digital Oscilloscope
QS01020-E02A

Copyright Information
SIGLENT TECHNOLOGIES CO., LTD. All Rights Reserved.
Declaration
SIGLENT products are protected by patent law in and outside of P.R.C.
SIGLENT reserves the right to modify or change parts of or all the specifications or pricing
policies at company’s sole decision.
Information in this publication replaces all previously corresponding material.
Any way of copying, extracting or translating the contents of this manual is not allowed
without the permission of SIGLENT.
Note: SIGLENT is the registered trademark of SIGLENT TECHNOLOGIES CO., LTD.
Contact us
SIGLENT TECHNOLOGIES CO., LTD.
Address：3/F, building NO.4, Antongda Industrial Zone, 3rd Liuxian Road, Bao’an District,
Shenzhen, P.R.C.
Tel:[phone]
E-mail:[email protected]
Http://www.siglent.com
SIGLENT
General Safety Summary
Carefully read the following safety precautions to avoid any
personal injury or damage to the instrument and any
products connected to it.To avoid potential hazards,please
use the instrument as specified.
Use Proper Power Line
Only the power cord designed for the instrument and
authorized by local country could be used.
Ground the Instrument
The instrument is grounded through the protective earth
conductor of the power line. To avoid electric shock,
please make sure the instrument is grounded correctly
before connecting its input or output terminals.
Connect the Signal Wire Correctly
The potential of the signal wire is equal to the earth, so
do not connect the signal wire to a high voltage.
Look Over All Terminals’ Ratings
To avoid fire or electric shock, please look over all ratings
and sign instruction of the instrument. Before connecting
the instrument, please read the manual carefully to gain
more information about the ratings.
Use Proper Overvoltage Protection
Make sure that no overvoltage(such as that casued by a
thunderstorm) can reach the product, or else the operator
might expose to danger of electrical shock.
Electrostatic Prevention
Operate in an electrostatic discharge protective area
environment to avoid damages induced by static
discharge. Always ground both the internal and external
conductors of the cable to release static before
connecting.
Keep Well Ventilation
inadequate ventilation may cause increasing of
temperature, which will eventually damage the
instrument. So keep well ventilation and inspect the
intake and fan regularly.
Avoid Circuit or Components Exposed
Do not touch exposed contacts or components when the
power is on.
Use Only the Specified Fuse.
Do Not Operate Without Covers
Do not operate the instrument with covers or panels
removed.
SIGLENT
SDS2000 Quick Start I

Safety Terms and Symbols
Terms on the product. These terms may appear on the
product:
DANGER Indicates direct injuries or hazards that may
happen.
WARNING Indicates potential injuries or hazards that
may happen.
CAUTION Indicates potential damages to the instrument
or other property that may happen.
Symbols on the product. These symbols may appear on
the product:
General Care and Cleaning
Care
Notice:
Cleaning
Please perform the following steps to clean the
instrument and probe regularly according to its operating
conditions.
Notice:
Hazardous
Voltage
Warning Protective
Earth Ground
Earth
Ground
Chassis
Ground
SIGLENT
1. Disconnect the instrument from all power sources, and
then clean it with a soft wet cloth.
2. Clean the loose dust on the outside of the instrument
and probe with a soft cloth. When cleaning the LCD,
take care to avoid scarifying it.
To avoid damages to the surface of the instrument and
probe, please do not use any corrosive liquid or chemical
cleanser.
Make sure that the instrument is completely dry before
restarting it to avoid short circuits or personal injuries.
To avoid damages to the instrument or probe, please
do not leave them in fog, liquid, or solvent.
Do not store or leave the instrument in direct sunshine for
long periods of time.
II SDS2000 Quick Start
Contents
General Safety Summary I
Safety Terms and Symbols
General Care and Cleaning II
1Quick start
General Inspection
Appearance and Dimension
1
Adjust the Supporting Legs 2
Connect to AC Power Supply 2
Power-on Inspection 3
Connect the Probe 3
Function Inspection 3
Probe Compensation 4
The Front Panel 5
The Rear Panel 6
Introduction of Front Panel 7
Horizontal Control 7
Trigger Control 7
Vertical Control 11
SIGLENT
SDS2000 Quick Start III
II
1

Contents
General Safety Summary I
Safety Terms and Symbols
General Care and Cleaning
II
1Quick start
General Inspection
Appearance and Dimension 2
Adjust the Supporting Legs 2
Connect to AC Power Supply 2
Power-on Inspection 3
Connect the Probe 3
Function Inspection 3
Probe Compensation 4
The Front Panel 5
The Rear Panel 6
Introduction of Front Panel 7
Horizontal Control 7
Trigger Control 7
Vertical Control 11
Run Control 13
Universal Knob 14
Function Menus 14
User Interface 16
Using Security Lock 18
2 Troubleshooting 18
SIGLENT
IV SDS2000 Quick Start
General Inspection
1. Inspect the shipping container
Keep the damaged shipping container or cushioning
material until the contents of the shipment have been
completely checked and the instrument has passed
both electrical and mechanical tests.
The consigner or carrier will be responsible for
damages to the instrument resulting from shipment.
SIGLENT would not provide free maintenance or
replacement.
2. Inspect the instrument
If there are instruments found damaged, defective or
failure in electrical and mechanical tests, please
contact SIGLENT.
3. Check the accessories
Please check the accessories according to the packing
list. If the accessories are incomplete or damaged,
please contact your SIGLENT sales representative.
Appearance and Dimension
Quick start
Figure 1 Front View
Figure 2 TopView
SIGLENT
352mm
224mm
128mm
SDS2000 Quick Start 1

Adjust the Supporting Legs
Adjust the supporting legs properly to use them as stands
to tilt the oscilloscope upwards for stable placement as
well as easier operation and observation of the
instrument.
Connect to AC Power Supply
The oscilloscope accept 100-240V, 45-440Hz AC power
supply. Please use the power cord provided as
accessories to connect the instrument to the power
source as shown in the figure below.
Before adjusting After adjusting Power
Socket
Note: In want of replacing the fuse, please return the
instrument to the factory that produced it to have
it repaired by qualified service personnel authorized
by SIGLENT.
SIGLENT
2 SDS2000 Quick Start
Function Inspection
1. Press to restore the oscilloscope to its default
setup.
Power-on Inspection
When the scope is energized, turn on the power switch at
the lower left corner on the front panel. During the
start-up process, the instrument performs a series of
self-test items and you can hear the sound of relay
switching. After the self-test completed, the User
Interface displays immediately.
Connect the Probe
SIGLENT provides passive probe for the SDS2000 series
oscilloscope. Please refer to corresponding Probe User
Manual for detailed technical information.
Connect the probe:
1. Connect the BNC terminal of the probe to one of the
channel BNC connector of the front panel.
SIGLENT
2. Connect the probe tip to the circuit point to test and the
ground alligator clip of the probe to the ground terminal
of the circuit.
2. Connect the ground alligator clip of the probe to the
Ground Terminal on the front panel.
3. Use the probe to connect the CH1 Input Terminal and the
Compensation Signal Output Terminal on the front panel.
4. Press
5. Observe the waveform on the screen. In normal condition,
the display should be a square waveform as shown in the
below:
Ground Terminal
Compensation Signal Output Terminal
SDS2000 Quick Start 3

Power-on Inspection
When the scope is energized, turn on the power switch at
the lower left corner on the front panel. During the
start-up process, the instrument performs a series of
self-test items and you can hear the sound of relay
switching. After the self-test completed, the User
Interface displays immediately.
Connect the Probe
SIGLENT provides passive probe for the SDS2000 series
oscilloscope. Please refer to corresponding Probe User
Manual for detailed technical information.
Connect the probe:
1. Connect the BNC terminal of the probe to one of the
channel BNC connector of the front panel.
Probe Compensation
You should properly compensate the probe at first use of
it. Non-compensated or inadequate compensated probe
may cause inaccurate measurement. The following steps
are about probe compensation:
1. Perform step 1, 2 , 3 and 4 of “Function Inspection”.
2. Check the displayed waveforms and compare them
with the following figure.
Note: To avoid electric shock when using the probe,
please firstly make sure that the insulated wire
of the probe is in good condition, and do not touch
the metallic part of the probe when it is connected
to a high voltage.
Under
Compensated
Compensated
Correctly
Over
Compensated
SIGLENT
6. Test the other channels in the same method. If the
actual square waveforms does not match that in the
figure above, please perform “Probe Compensation”.
3. Use a nonmetallic driver to adjust the low-frequency
compensation adjustment hole on the probe until the
waveform changes to be correct as the figure above.
4SDS2000 Quick Start
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4
5
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18
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9
1. Horizontal Control
2. Auto Setup
3. Run/Stop
4. WaveGen
5. Default Setup
6. Universal Knob
7. Trigger Control
8. Decode Control
9. Digital Channel Control
10.MATH/Ref Vertical Control
11. Function Menus
12. MATH Function
13. Ref
14. Channel Vertical Control
15. WaveGen Output
16. Probe Compensation/Ground Terminal
17. USB Host
18. Digital Channel Inputs
19. Function Menu Softkeys
20. Analog Inputs 21. Power On/Off
SIGLENT
The Front Panel
SDS2000 Quick Start 5

The Rear Panel
1
2
3
4
5
6
7
1. Handle
Pull up the handle vertically for easy
carrying; press it down if you do not
need the handle.
2. EXT TRIG Connector
3. Pass/Fail or Trig Out Output
Via this interface the oscilloscope can
output a signal that can reflect the
current capture rate of the instrument
at each trigger or a Pass/Fail pulse.
4. LAN Interface
The instrument can be connected to
network via this interface to perform
remote control.
5. USB Device
PictBridge printer or PC can be connected via this interface to print the current interface of the oscilloscope
or control the instrument through PC software.
6. Lock Hole
You could lock the instrument in a fixed location using a security lock (please buy it yourself) via the lock hole.
7. AC Power Socket
The standard power supply for the instrument is 100~240V，45~440Hz. Please use the power cord provided
as accessories to connect the instrument to AC power.
SIGLENT
6 SDS2000 Quick Start
SIGLENT
Front Panel Function Brief
Horizontal Control
Trigger Control
Horizontal POSITION
Horizontal Time Base
：Press the button to open trigger menu. This
oscilloscope provides various trigger types: Edge, Slope,
Pulse, Video, Window,Interval, DropOut, Runt, Pattern
and Serial Bus（I2C/SPI/UART/RS232/CAN/LIN）.
We will introduce Video, Interval, Runt, Pattern and
Serial Bus trigger in the following.
HDTV Video Trig ger
Analog video signal includes NTSC and PAL and HDTV
signal are supported in SDS2000 oscilloscopes. In video
operation, you can select Custom to set any line and field.
nss
：Modify the trigger position.
The waveform will move left or right when you revolve
the knob. Meanwhile, the Delay value will also increase
or decrease as the the waveform moves. Press down
the knob to return the waveform to horizontal center
of the screen.
：Modify the horizontal
time base.Turn it clockwise or counterclockwise to
reduce or increase the time base. The waveform will
display expanded or compressed and the time base
message at the upper left of the screen will change
as the time base changes.
：Press
the button to open
waveform display
mode menu. The
selectable modes
include: X-Y/Y-T/ROLL.
：Press the button to open delay sweep function.
Press again to turn it off.
SDS2000 Quick Start 7

Interval Trigger
The time interval from the rising edge (or falling edge) of
input signal passes through the trigger level to the next
rising edge(or falling edge) passes through the trigger
level and the currently set time satisfy the Limit Range
（＜，＞，＜ ＞，＞ ＜）selected.
In the figure below, the time interval between two
continuous rising edge and the currently set time satisfy
the limit range (＜＞).
SIGLENT
Runt Trigger
Runt trigger includes positive runt trigger and negative
runt trigger.This trigger mode is used to trigger pulses
that pass through one trigger level but fails to pass
through the other trigger level as shown in the figure below.
High Level
Low Level
Negative runt pulse
Positive runt pulse
In the figure below, the trigger signal are positive runt pulse.
8 SDS2000 Quick Start
Pattern Trigger
Identify a trigger condition by looking for a specified
pattern. This pattern is a logical combination
(AND/OR/NAND/NOR) of the two channels. Each
channel can be set a value among High, Low or Invalid.
In the figure below, the selected logic is “AND”, both
channel 1 and 2 are set “High”.
SIGLENT
I2C Trigger
After setting the serial 1 or 2 to I2C type in trigger menu,
you can use universal knob to set to trigger on start/stop
condition, restart, no ack,EEPROM, or on the read/write
frame with specific device address and data value. During
I2C trigger settings, it is essential to set source channel
previously in decode menu.
In the figure below,the trigger condition is set to “start”,
channel 1 is set as Data signal, channel 2 is set as
Clock signal.
SDS2000 Quick Start 9

SPI Trigger
After setting the serial trigger to SPI type in trigger menu,
you can select to trigger on MISO data or MOSI data.
The data length are variable to set from 4 to 96.
UART/RS232 Trigger
After setting the serial trigger to UART/RS232 type in
trigger menu, you can select to trigger on start , stop,
checksum error or data. The data width are variable to
set from 5 to 8bits.
CAN Trigger
After setting the serial trigger to CAN type in trigger
menu, you can select to trigger on start, remote, ID,
ID+DATA or Error of CAN-H or CAN-L signal.
LIN Trigger
After setting the serial trigger to LIN type in trigger menu,
you can select to trigger on Start, ID, ID+DATA or
Data+Error.
SIGLENT
Level
：Press the button to set to Normal trigger mode.
：Press the button to set to Single trigger mode.
：Press the button to set to Auto trigger mode.
Notes：for more trigger types and corresponding operation
information, please refer to the trigger chapter of
User Manual.
：Modify the trigger level. Turn it clockwise
or counterclockwise to make the level move up or down.
In the meanwhile, the level value displayed at the upper
right of the screen will increase or decrease. Press it
down to quickly reset the trigger level to the vertical center
of corresponding waveforms.
10 SDS2000 Quick Start
Vertical Control
SIGLENT
POSITIONVertical
：Analog input channels. The four channels
are marked by different colors which are also used to
mark both the waveforms on the screen and the
channel input connectors. Press channel button to
open the corresponding channel and press again to
turn it off.
：Modify the vertical position
of current waveform. Turn clockwise to increase the
position while turn counterclockwise to decrease.
During the modification, the waveform will move up
and down and the position message at the lower part
of the screen will change along. Press down the knob
to quickly reset the vertical position to zero.
Vertical Scale
mVV
：Modify the vertical scale of current
waveform. Turn clockwise to decrease the scale while
turn counterclockwise to increase it. During the modification,
the amplitude of the waveform will enlarge or reduce and
the scale message at the right side of the screen will also
change. Press down the knob to quickly switch the vertical
scale adjustment modes between “Coarse” and “Fine”.
：Decoding function button.
Press it to open decode menu.
SDS2000 supports two serial buses
including 1 and 2 for analog signal
(CH1/CH2/CH3/CH4) decoding.
The protocols includes I2C, SPI,
UART/RS232, CAN and LIN.
SDS2000 Quick Start 11

SIGLENT
Vertical POSITION
：Modify the vertical position of
Math/Ref waveform. Turn clockwise to increase the
position while turn counterclockwise to decrease. During
the modification, the waveform will move up and down
and the position message at the lower part of the screen
will change along. Press down the knob to quickly reset
the vertical position to zero.
：Digital channel function button. Press the
button to open digital channel menu. SDS2000 supports
8 integrated digital channels.
：Press the button to open math operation menu
under which the operation of adding, subtracting,
multiplying, dividing, FFT, integral, differential and sqare
are supported.
：Press the button to enable the reference
waveform function, thus to compare the current waveform
with the reference waveform to decide circuit failures.
SDS2000 supports 4 reference waveforms saving.
Vertical Scale
：Modify the vertical scale of
Math/Ref waveform. Turn clockwise to decrease the
scale while turn counterclockwise to increase it.
During the modification, the amplitude of the waveform
will enlarge or reduce and the scale message at the
middle of the screen will also change. In addition, the
knob can be used to select a digital channel.
Decoding for I2C signal of 7 address is described in
the following figure.
12 SDS2000 Quick Start
Run Control
SIGLENT
：Press the button to enable the waveform auto
setting function. The oscilloscope will automatically adjust
the horizontal time base, vertical scale and trigger mode
according to the input signal to make the waveform
displays in a perfect state.
：Press the button to set the state of the
instrument to “RUN” or “STOP”.
In “RUN”state, the indicator light displays yellow;
In “STOP”state, it displays red.
：Press the button to open the WaveGen menu.
SDS2000 provides built-in signal generator function. Ten
types of signal including Sine, Square, Ramp, Pulse, DC,
Noise, Cardiac, Gaus Pulse, Exp Rise and Exp Fall are
supported.The most output frequency is 25MHz
In addition, the insrtument can output any waveforms by
connecting EasyWave software through remote conrtol.
SDS2000 Quick Start 13
Press the button to reset the oscilloscope to its
default setup. The default voltage scale and timebase are
respectively 1V/div and 1us/div.

Universal Knob Function Menus
Universal Knob:
In menu operation,when the light below the knob is lighted,
you could revolve the knob to select between submenus
under the current menu and press it down to select the
current submenu. In addition, it can also be used to modify
parameters and input filename.
SIGLENT
：Press the button to enter the cursor measurement
menu. The instrument provides Time and Voltage measure.
：Press the button to enter the display menu to
set waveform Type, Color, Persist , Clear Display, Grid,
Intensity, Brightness and Transperancy.Transperancy
indicates the display transperancy of any popup messagebox.
For instance, you could use universal knob to adjust
transperancy of the messagebox when Cursor Measurement
is on.
：Press the button to enter the utility menu to set
system-related functions or parameters, such as IO Set,
Sound, language. In addition, some advanced functions
(such as Pass/Fail test, Print Setup, Do Self Test and Update)
are also supported.
Adjust Waveform Intensity/Grid Brightness/Transpanrency
In non-menu-operation mode, (menu is hidden),turn this
knob to adjust waveform intensity (0% ~ 100%). Turn
clockwise to increase the brightness and counterclockwise
to reduce. You can also press Display → Intensity and
use the knob to do adjusting. To adjust grid brightness
(0% ~ 100%）or transparency(20% ~ 80%）,please
operate in the same way as waveform intensity.
14 SDS2000 Quick Start SDS2000 Quick Start 15
SIGLENT
：Press the button to enable HELP function,and
then press down any menu to display corresponding help
information.To display the submenus help information of
the current menu, firstly you should open the current menu,
and then press down the “HELP” button, the last step is to
select any submenu you want.
：Press the button to enable print function. If the
instrument is connected to a printer which is usable, press
it to perform print function.
：Press the button to enter the measurement
setting menu. You could set measurement setting,
statistic function and all measure. In measurement
setting, you could select as many as five parameters
and display them simultaneously on the screen. In
statistic function,the curent value, Mean value,
Min value, Max value, Std-Dev and Counts are
displayed on the screen. In all measure, you could
display all Voltage/Time/Delay parameters by pressing
the corresponding softkey.
：Press the button to enter the sample setting
menu to set the acquisition mode (Normal/Peak Detect/
Average/High Res), dot inserting mode and memory
depth (7K/14K/70K/140K/700K/1.4M/7M/14M).
：Press the button to enter the file save and
recall function menu. the storable file types includes
Setups, Waveforms, Picture and CSV.

User Interface
SIGLENT
1
2
8345
6
7
9
10
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5. Trigger Position
Use horizontal POSITION knob to modify the parameter. Turn clockwise or
counterclockwise to make the waveform move right or left, which will respectively
cause the Delay parameter to decrease or increase. Press down the knob to
automatically reset the parameter to zero as well as make the waveform return to
horizontal center of the screen.
1. Product Logo
SIGLENT is the registered
trademark of our company.
2. Channel Label/Waveform
Different channels are marked
by different colors and the color
of the waveform complies with
the color of the channel.
3. Working state
Available states include Arm、
Ready、Trig’d、Stop、Auto.
4. Horizontal Time Base
Represent the time of each grid
on the horizontal axis of the
screen. You could revolve
to modify the parameter which
is variable from1ns ~ 50s.
sns
16 SDS2000 Quick Start
6. Trigger position
Display the trigger position of the waveform on the
screen.
7. USB Device Interface Mark
Indicate the current set of USB Device Interface. If the
icon displays , the interface is set to USBTMC，
if the icon display , the interface is set to Printer.
8. Frequency Counter
Display the firmware frequency of current waveform.
9. Sample Rate/Memory Depth
Display the current sample rate and memory depth of
the oscilloscope. Use horizontal SCALE knobe to
modify the parameter.
10. Trigger Setting
Trigger Source Display the trigger source
currently selected. Different labels are displayed when
different trigger source are selected and the color of
the trigger parameter area will change accordingly.
Coupling Mode Display coupling mode
(DC/AC/LF Reject/HF Reject) of the current trigger
source.
Trigger Level Display the trigger level
value of the current waveform. Press down the knob
to reset the parameter to zero.
For example: means triggered on Slop side in edge trigger.
11. Channel Setting
Probe Attenuation Factor Display currently selected
probe attenuation factor.All factors are: 1X/5X/10X/50X
/100X/500X/1000X.
Channel Coupling Display the selected coupling
mode of the current channel.All modes are: DC/AC/GND.
Voltage Scale Represent the voltage value of
each grid on the vertical axis of the screen.Use POSITION
knobe to modify the parameter which is variable from
BW Limit If the current “BW Limit” is “On”, then the
mark displays. When the vertical scale is 2mV/div, the
“BW Limit” turns on automatically.
Impedance Display currently selected
impedance(1MΩ/50Ω) of the channel.
12. Trigger Level Position
Display position of the current channel trigger level. Press
down the konb to reset the level to vertical center of the
screen.
13. Menu
Display menus of the currently selected function module.
Press any menu softkey to perform corresponding setting.
CH1
DC
L 0.00mV
Edge
1X
DC
1MΩ
B
B
1.00V/div
SIGLENT
Trigger Type Display the currently selected trigger
type and trigger condition setting. Different labels are
displayed when different trigger types are selected.
SDS2000 Quick Start 17

Using Security Lock
If needed, you could use the security lock (please buy it
yourself) to lock the instrument in a fixed location. The
method: align the clock with the clock hole and plug it into
the lock hole vertically, turn the key clockwise to lock the
instrument and then pull the key out.
The general failures and consequential solutions are
listed below. When you find them, please deal with them
in the following corresponding ways. If the problem
proves to be unsolvable by yourself, please contact with
SIGLENT as soon as possible.
1. The screen remains dark after power on:
（1）Check if the power is correctly connected.
（2）Check if the power switch is faulted.
（3）Check whether the fuse is burned out. If the fuse
needs to be changed, please contact with
SIGLENT as soon as possible and return the
instrument to the factory to have it repaired by
qualified personnel authorized by SIGLENT.
（4）Restart the instrument after completing inspections
above.
（5）If it still does not work normally, please contact
SIGLENT.
2. After the signal is sampled, there is no corresponding
waveform displaying:
(1) Check if the probe is correctly connected to the
signalconnecting cord.
Security
lock hole
Troubleshooting
SIGLENT
18 SDS2000 Quick Start
5. No display after pressing :
Check whether the trigger Mode is “Normal” or “Single”,
and if the trigger level exceeds the waveform range. If
yes, set the trigger level to the middle or change the
trigger Mode to “Auto”.
Note: press “Auto Scale” could automatically replace the
above setting.
6. The waveform displays like ladder:
（1）The horizontal time base may be too low, you can
increase it to improve the horizontal resolution so as to
make a good waveform displaying.
（2）The lines between the sample points may also cause
ladder-like displaying if the “Type” in menu of
“DISPLAY” is “Vectors”. Please turn the “Type” to
“Dots” to solve the problem.
7. USB storage can’t be recognized:
（1）Check if the USB flash disk can work normally.
（2）Check if the USB Device Host can work normally.
（3）Make sure the USB disk being used is of flash type,
the instrument does not support USB of hardware type.
（4）Make sure the system format of used USB disk is FAT32.
（5）Restart the instrument and then insert the USB to check it.
（6）If it is still in abnormal use, please contact with SIGLENT.
SIGLENT
（2）Check if the signal connecting cord is correctly
connected to BNC.
（3）Check if the probe is correctly connected to the
item under test.
（4）Check if there are signal generated from the item
under test.
（5）Resample the signal.
3. The voltage amplitude measured is higher or lower
than the actual value (the error usually occurs in use of
the probe):
Check if the attenuation coefficient of the current channel
matches with the attenuation ratio of the probe.
4. There is waveform displaying but not stable:
（1）Check the trigger source: check whether the “Source”
in menu of “TRIG” is the actual operating channel.
（2）Check if the waveform is wrong: it is easy for us to
regard the wrong waveform as the real when a high
frequency signal is connected to the instrument.
You’d better make sure that the current time base is
correct.
（3）Check the trigger type: “Edge” trigger suits to general
signal and “Video” trigger suits to video signal. Only in
correct trigger type can the waveform stably displays.
（4）Change the setting of trigger holdoff.
SDS2000 Quick Start 19