Tenma 72-2650 User manual

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Digital Storage Oscilloscope
Model No. 72-2650, 72-8705A, 72-8710A
72-8225A & 72-10510

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When using electrical appliances, basic safety precautions should always
be followed to reduce the risk of re, electric shock and injury to persons or
property.
Read all instructions before using the appliance and retain for future reference.
• This meter is designed to meet IEC61010-1, 61010-2-032, and 61010-2-033 in
Pollution Degree 2, Measurement Category (CAT II 150V when switched to 1X and
300V CAT II when switched to 10X) and double Insulation.
• Check that the voltage indicated on the rating plate corresponds with that of the
local network before connecting the product to the mains power supply.
• Do not operate this product with a damaged plug or cord, after a malfunction or
after being dropped or damaged in any way.
• Check the product before use for any damage. Should you notice any damage on
the cable or casing, do not use.
• This product contains no user-serviceable parts. All repairs should only be carried
out by a qualied engineer. Improper repairs may place the user at risk of harm.
• Take caution when voltages are above 60V DC and 30V ACrms.
• The earth probe must only be used to connect to ground, never connect to a
voltage source.
• This product must be earthed using the mains power cord ground connection.
• Do not disconnect from the mains supply and it’s ground connection when any item
is connected to this product for measurement.
• Children should be supervised to ensure that they do not play with the product.
• Always disconnect from the mains when the product is not in use or before
cleaning.
• Do not use the product for any purpose other than that for which it is designed.
• Do not operate or store in an environment of high humidity or where moisture may
enter the product as this can reduce insulation and lead to electric shock.
PRODUCT OVERVIEW
Main Features
• Dual analogue channels with HD colour LCD display
• Automatic waveform and status conguration
• Multi‐waveform mathematical operation function
• Automatic measurement of 28 waveform parameters
• Edge, video, pulse width and alternate trigger functions
• Supports plug and play USB storage devices and communication with PC
• Built‐in FFT software function
• Unique waveform recording and replay function
WHAT’S INCLUDED
• Digital Oscilloscope Unit
• Mains power lead
• User Manual
• Communications software CD
• USB lead
• 2 x selectable 1:1/10:1 passive voltage probes
Optional accessories
• LAN port module

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CONTROLS AND CONNECTIONS
OPERATING PARAMETERS
• The oscilloscope also has high performance index and powerful functions required
for faster measurements. Faster signals can be observed with the oscilloscope
via 500MS/s (or 1GS/s) real‐time sampling and 25GS/s (or 50GS/s) equivalent
sampling.
• Powerful trigger and analysis ability make it easier to capture and analyse
waveforms.
• Clear LCD and mathematical operating functions make it easy to use to observe
and analyse signal problems in a faster and clearer way.

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Accessing signals
• Power on the unit then allow the self test to complete.
• Press UTILITY button then F1 and the screen will display DEFAULT SETUP.
Note: The meter has dual input channels plus one external trigger input channel.
• Press CH1 to enter channel 1 menu.
• Connect the probe to the Ch1 input.
• Set the probe attenuation switch to 10X position.
Note: The oscilloscope attenuation has to be set as well.
• Press F4 until 10X displays. This changes the vertical range multiple to ensure the
measurement result correctly reects the amplitude of the measured signal.
• Connect both probe and ground clamp to the corresponding signal terminals.
• Press AUTO and a square wave of about 3V at 1kHz is displayed for a moment.
• Press OFF then CH2 and repeat for channel 2.
OPERATION
AUTOSET WAVEFORM DISPLAY
Probe compensation
• Perform this adjustment when connecting the probes to any input channel for the
rst time or errors in the measurement may result.
• Connect the probe tip to the probe compensator’s signal output connector and
connect the ground clamp to the earth wire of the probe compensator.
• Enable CH1 and press AUTO.
• Observe the shape of the displayed waveform.
• Adjust the variable capacitor on the probe with an insulated screwdriver until a
correct waveform is achieved.
• The oscilloscope features an AUTOSET function which automatically adjusts the
vertical deection factor, scanning time base and trigger mode based on the input
signal until the most appropriate waveform is displayed.
• This function only operates when the signal to be measured is 50Hz or above and
the duty ratio is larger than 1%.

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DISPLAY SETTING CONTROLS
Using the AUTOSET function
• Connect the signal to be measured to the signal input channel.
• Press AUTO and the oscilloscope will scan the time base and trigger mode and set
the vertical deection factor. You can manually adjust further after this process to
get the optimum display.
Vertical control panel
• Vertical position control centres the waveform display.
• As you adjust the position the GROUND channel indicator
moves in line with the waveform.
• Pressing SET TO ZERO resets the display to the centre point.
• Adjusting the vertical scale control adjusts the VOLT/DIV range.
The current status display changes accordingly.
• Press CH1, CH2, MATH or REFERENCE and the screen shows
the corresponding operation menu, sign, waveform and range
status information.
• Press OFF to disable the selected channel (72-2650).
Horizontal control panel
• Horizontal position control adjusts the position of the waveform window by
adjusting the trigger shift of the signal.
• The horizontal scale adjustment changes the SEC/DIV time base range
and the current status indicator will change accordingly.
• The horizontal scanning rate range is 5ns - 50ns in steps of 1-2-5-10.
Note: the horizontal scanning time base range varies between models - see
table in specication section.
• Pressing SET TO ZERO resets the display to the centre point.
Zoom display option
• Press MENU to display the ZOOM options.
• Press F3 to display further options including WINDOW EXPANSION and
HOLDOFF.
• Rotate the MULTI FUNCTION rotary control to make adjustments.
• Press F1 to quit the option and return to MAIN TIME BASE.
Trigger system
• The trigger level rotary control adjusts the trigger level. The display value changes
on the display as you make adjustment.
• Press MENU to select the trigger options.
• Press F1 and set EDGE TRIGGER
• Press F2 and set TRIGGER SOURCE to CH1
• Press F3 and set EDGE TYPE as RISING
• Press F4 and set TRIGGER MODE as AUTO
• Press F5 and set TRIGGER COUPLING as DC
• Press 50% to set trigger level at the range amplitude centre
point (trigger zero - highest sensitivity setting)
• Press COMPULSORY to generate a compulsory trigger signal
mainly used in normal and single trigger modes.

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INSTRUMENT SETUP
Vertical system setup
• Each channel CH1 or CH2 has it’s own vertical menu. Each channel should be set
up individually.
• Press CH1 or CH2 and the system will display the operation menu for that channel.
Channel coupling setup
• If for example a signal is applied to CH1
which has a sine signal that contains DC
quantities.
• Press F1 to select AC and set up as AC
coupling. Any DC quantities in the signal are
now intercepted.
• Press F1 to select DC.
• Both AC and DC quantities of the signal
being measured can now pass through.
• The waveform displays both AC and DC
quantities of the signal.
• Press F1 to select GROUND.
Both AC and DC quantities of the signal
being measured are now intercepted.
• The waveform is not displayed in this mode
but the signal remains connected to the
channel circuit.
Functions Menu Setup Notes
Coupling
AC Intercepts the DC quantities of the input signal.
DC Pass AC and DC quantities of input signal
GROUND Disconnect input signal
Bandwidth Limit On Limit bandwidth to 20MHz to reduce noise display.
Off Full bandwidth
Volts / DIV
Coarse tune Coarse tune in steps of 1-2-5 to set up the
deection factor of the vertical system.
Fine tune Fine tune is further tuning within the coarse tune
set up to improve the vertical resolution.
Probe
1X, 10X,
100X and
1000X
Select either value based on the probe attenuation
factor to keep the vertical deection factor reading
correct.
Invert On Waveform invert function on.
Off Normal waveform display.

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Channel bandwidth setup
• If for example a signal is applied to CH1
which is a pulse signal that contains high
frequency oscillation.
• Press CH1 to select Channel1.
• Press F2 to set the BANDWIDTH LIMIT
OFF so it is set up as full bandwidth.
• The signal being measured can now pass
through even if it contains high frequency
quantities.
• Press F2 to set BANDWIDTH LIMIT ON
so that frequency quantities higher than
20MHz in the signal being measured will be
limited.
Probe rate setup
• To match the probe attenuation
factor setup, it is necessary to set up
the probe attenuation factor in the channel
operation menu accordingly.
• For example when the probe attenuation
factor is 10:1, set the probe attenuation
factor at 10X in the menu. This principle
applies to other values to ensure the voltage
reading is correct.
Waveform inversion setup
• The displayed signal is inverted 180
degrees with respect to the ground level.
Vertical Volts/Div adjustment setup
• The VOLTS/DIV range of the vertical
deection factor can be adjusted either in
coarse or ne tune mode.
• In COARSE TUNE the VOLTS/DIV range is
2mV/div~5V/div. Tuning is in steps of 1-2-5.
• In FINE TUNE mode the deection factor
can be adjusted in smaller steps allowing
continuous adjustment within the range
2mV/div~5V/div without interruption.

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Operating Math functions
• Math functions are displays of +, -, x, ÷and
FFT mathematical results of CH1 and CH2.
The menu options are:-
FFT spectrum analysis
• Using FFT algorithm you can convert the domain signals (YT) into frequency
domain signals.
• With FFT you can observe the following types of signals:
1. Measure the harmonic wave composition and distortion of the system.
2. Demonstrate the noise characteristics of the DC power.
3. Analyse oscillation.
• Signals with DC quantities or DC offset will cause error or offset FFT waveform
quantities. To reduce DC quantities select AC coupling.
• To reduce random noise and frequency aliasing as a result of repeated or single
pulse event, set the acquired mode of the oscilloscope to average acquisition.
Functions Menu Setup Notes
Type Math To carry out +, -, x, ÷ functions
Signal source 1 Ch1
Ch2
Set signal source 1 as CH1 waveform
Set signal source 1 as CH2 waveform
Operator +
-
x
÷
Signal source 1+
Signal source 2
Signal source 1-
Signal source 2
Signal source 1x
Signal source 1
Signal source 1÷
Signal source 2
Signal source 2 Ch1
Ch2
Set signal source 2 as CH1 waveform
Set signal source 2 as CH2 waveform
Functions Menu Setup Notes
Type FFT To carry out FFT algorithm functions
Signal source Ch1
Ch2
Set CH1 as math waveform
Set CH2 as math waveform
Window
Hanning
Hamming
Blackman
Rectangle
Set Hanning window function
Set Hamming window function
Set Blackman window function
Set Rectangle window function

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Select the FFT window
• Assuming the YT waveform is constantly repeating itself, the oscilloscope will carry
out FFT conversion of time record of a limited length. When this cycle is a whole
number, the YT waveform will have the same amplitude at the start and nish.
There is no waveform interruption.
• If the YT waveform cycle is not a whole number there will be different amplitudes
at the start and nish, resulting in transient interruption of high frequency at the
connection point. In frequency domain this is known as leakage.
• To avoid leakage multiply the original waveform by one window function to set the
value at 0 for start and nish compulsively. See the following table:
Reference waveform
• Displays of the saved reference waveforms can be set on or off in thee REF menu.
• The waveforms are saved in non-volatile memory and identied with the following
names: Ref A, Ref B.
• To display (recall) or hide the reference waveforms use the following method:
1. Press REF menu button on the front panel
2. Press REF A (reference option)
3. Select the signal source and the position of the signal source 1~10 by use of the
multi-function rotary control.
4. Press RECALL to display the waveform stored in that location.
Note: If the stored waveform is on external disk press F2 to select between DSO and
USB and select USB having inserted the drive into the USB port.
5. The recalled waveform will be displayed on the screen.
6. Press CANCEL to go back to the previous menu.
FFT Window Feature Most suitable measurement item
Rectangle
The best frequency resolution,
the worst amplitude resolution.
Basically similar to a status
without adding window.
Temporary or fast pulse. Signal level is
generally the same before and after.
Equal sine wave of very similar frequency.
There is broad-band random noise with
slow moving wave spectrum.
Hanning
Frequency resolution is better
than the rectangle window but
amplitude resolution is poorer.
Sine, cyclical and narrow-band random
noise.
Hamming
Frequency resolution is
marginally better than Hanning
window.
Temporary or fast pulse. Signal level varies
greatly before and after.
Blackman
The best amplitude resolution
and the poorest frequency
resolution.
Mainly for single frequency signals to
search for higher-order harmonic wave.
Note: FFT resolution means the quotient of the sampling and math points. When the
math point value is xed, the sampling rate should be as low as possible relative to the
FFT resolution.
• Nyquist frequency: To rebuild the original waveform, at least 2f sampling rate
should be used for waveform with a maximum frequency of f.
• This is known as Nyquist stability criterion, where f is the Nyquist frequency and 2f
is the Nyquist sampling rate.

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7. Press REF B and select the second signal source for the math function repeating
step 3
Note: To measure and observe such waveforms you can compare the current waveform
with the reference waveform for analysis.
8. Press REF to display the reference waveform menu. See following table:
Functions Menu Setup Notes
Signal source selection 1~10 1~10 stands for positions of 10 groups of
waveforms respectively
Disk DSO
USB
Select an internal storage location
select an external storage position
(U disk must be connected)
Close -- Close the recalled waveform
Recall -- Recall the selected waveform
Cancel -- Go back to the previous menu
Functions Menu Setup Notes
Main time base --
1 - enable main time base
2 - if window extension is enabled, press main time
base to disable window extension
Window extension -- Enable time base
Holdoff -- Adjust Holdoff time
• To store to a selected location choose between 1 and 10. To use external USB, plug
in the U disk and press F2 to select the USB memory.
• To save a waveform press SAVE menu.
Horizontal system setup
• The horizontal rotary control is used to change the graticule (time
base) and trigger the horizontal position of the memory (triggering
position).
• The vertical centre point above the horizontal orientation of the
screen is the time reference point of the waveform. Changing the
graticule will cause the waveform to increase or decrease in size
relative to screen centre. When the horizontal position changes, the
position in respect to the waveform triggering point is also changed.
Horizontal position
• Adjust the horizontal positions of the channel waveforms (including
math waveforms). Resolution of this control changes with the time
base.
Horizontal scaling
• Adjusting the main time base i.e. sec/div. When time base extension
is on you can use the horizontal scaling control to change the delay
scanning time base and change the window width.

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Icon denitions
1. Represents the memory position of the current waveform.
2. Represents the memory position of the triggering point.
3. Represents the position of the triggering point in the current waveform window.
4. Horizontal time base (main time base) ie: sec/div.
5. Horizontal distance between the triggering position and the window centre point.
Denitions
• YT Mode: in this mode the y axis indicates voltage and the x axis indicates time.
• X-Y Mode: in this mode the X axis indicates CH1 voltage and the Y axis indicates
the CH2 voltage.
• Slow Scanning Mode: When the horizontal time base control is set at 50ms/div or
slower, the unit will operate in the slow scan sampling mode. When observing low
frequency signals in slow scanning mode, it is advised to set the channel coupling
as DC.
• Sec/Div: a horizontal scaling (time base) unit. If waveform sampling is stopped (by
pressing the RUN/STOP button) time base control can expand or compress the
waveform.
Window Extension
• Window extension can be use to zoom in or zoom out a band of waveform to check
image details. The window extension setting must not be slower than that of the
main time base.
• In the time base extension mode, the display
is divided into two zones as shown.
• The upper part displays the original
waveform. You can move this zone left or
right by turning the horizontal POSITION
control, or increase and decrease the
selected zone in size by turning the
horizontal SCALE control.
• The lower part is the horizontally extended
waveform zone.
• Please note that the resolution of extended
time base relative to the main time base is now higher as shown.
• Since the waveform shown in the entire lower part corresponds to the selected
zone in the upper part, you can increase the extended time base by turning the
horizontal SCALE control to decrease the size of the selected zone (increase the
multiple of waveform extension).
XY Mode
• This mode is suitable for CH1 and CH2 only. After
selecting the X-Y display mode, the horizontal axis will
display CH1 voltage, while the vertical axis will display
CH2 voltage.
Note: in the normal X-Y mode the oscilloscope can cause
the random sampling rate to acquire waveforms. To adjust
sampling rate and channel vertical range in the X-Y mode,
the omitted sampling rate is 100MS/s.

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• Generally adjusting the time base lower will result in appropriately Lissajous gures
of better display quality.
• The following functions have no effect in the X-Y display mode:-
1. Auto measurement mode
2. Cursor measurement mode
3. Reference or math waveform
4. Vector display type
5. Horizontal position control
6. Trigger control
Setting up the Trigger system
• Triggering decides when the oscilloscope collects data and displays waveforms.
Once the trigger is correctly set up, it can convert unstable display into signicant
waveforms.
• When beginning to collect data the oscilloscope rst collects sufcient data to draw
a waveform on the left of the triggering point.
• While waiting for the triggering condition to occur it will continuously collect data.
When sufcient data to draw a waveform on the right of the triggering point.
• The trigger control zone on the operation panel comprises a trigger level adjustment
control, a trigger MENU button, 50% button for setting up the trigger level at the
vertical centre point of the signal, and a COMPULSORY trigger button.
• Trigger level sets the signal voltage with respect to the triggering point.
• 50% sets the trigger level at the vertical centre point of the trigger signal amplitude.
• Compulsory used to generate a compulsory trigger signal, mainly used in the trigger
mode and normal and single modes.
• Menu button enables the trigger set up modes.
Trigger Control
• Trigger modes: Edge, Pulse, Video and Alternate.
Edge Trigger:
• When selecting edge trigger, you are triggering at the rising and falling edges of the
input signal.
Functions Menu Setup Notes
Type Edge
Signal source
selection
CH1
CH2
EXT
EXT/5
Set Ch1 as the signal source trigger signal
Set CH2 as the signal source trigger signal
Set the external trigger input channel as the signal source
trigger signal
Set the external trigger source divided by 5 to extend the
external trigger level range
Grid
Alternate
Set up as grid trigger
Ch1, CH2 trigger their own signals alternatively
Inclination Rising
Falling
Set to trigger on the signals rising edge
Set to trigger on the signals falling edge
Trigger Mode
Auto
Normal
Single
Set to sample waveform only if no trigger condition is detected
Set to sample waveform only if trigger condition is satised
Set to sample waveform once when detecting one trigger and
then stop

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Pulse Trigger
• Pulse trigger means determining the triggering time based on the pulse width. You
can acquire abnormal pulse by setting the pulse width condition.
• Adjust the pulse wit]width from 20ns~10s by turning the control on the upper front
panel.
Functions Menu Setup Notes
Type Edge
Trigger coupling
DC
AC
H/F reject
L/F reject
Intercept DC quantities of the input signal
Allow AC and DC quantities of the input signal to pass
Reject high frequency quantities above 80kHz of the signal
Reject low frequency quantities below 80kHz of the signal
Functions Menu Setup Notes
Type Pulse
Trigger source
CH1
CH2
EXT
Grid Alternate
Set Ch1 as the signal source trigger signal
Set CH2 as the signal source trigger signal
Set the external trigger input channel as the signal
source trigger signal
Set up as grid trigger
Ch1, CH2 trigger their own signals alternately
Pulse width
condition
Larger
Smaller
Equal
Trigger when pulse width is larger than default value
Trigger when pulse width is smaller than default value
Trigger when pulse width equals to default value
Trigger polarity Pos pulse width
Neg pulse width
Set positive pulse as the trigger signal
Set negative pulse width as the trigger signal
Trigger mode
Auto
Normal
Single
The system automatically samples waveform data
when there is no trigger signal input. The scan baseline
is shown on the display. When the trigger signal is
generates it automatically turns to trigger scan.
The system stops acquiring data when there is no
trigger signal. When the trigger signal is generated
trigger scan occurs.
One trigger will occur when there is an input trigger
signal. Then trigger will stop.

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Video Trigger
• By selecting video trigger you can carry out eld or line trigger with NTSC or PAL
standard video signals. Default trigger coupling is DC.
Alternate Trigger
• When alternate trigger is selected the trigger
signal will be present in two vertical channels. This
triggering mode is suitable for observing two signals
of unrelated signal frequencies.
Functions Menu Setup Notes
Type Video
Trigger source
CH1
CH2
EXT
EXT/5
AC Line
Set Ch1 as the trigger signal
Set CH2 as the trigger signal
Set the external trigger input channel as the trigger signal
Attenuate the external trigger source 5 times as the trigger
signal
Set AC power line as trigger signal
Standard PAL
NTSC
Suitable for video signals of low black level
Suitable for video signals of high black level
Synchronisation
All lines
Specied
lines
Odd eld
Even eld
Set the TV line to synchronise with trigger
Set synchronised trigger on the specied line and adjust by
turning the control on the front panel
Set video odd eld to synchronised trigger
Set video even eld to synchronised trigger
• When PAL is selected for STANDARD format and
SYNCHRONISATION mode is LINE you will see a
screen display similar to this:-
• When SYNCHRONISATION mode is FIELD you will
see a screen display similar to this:-

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Set up for Trigger Coupling mode
• Enter the trigger setup menu to set up the trigger coupling mode and achieve the
most stable synchronisation.
Adjusting the Holdoff time
• You can adjust the Holdoff time to observe
complicated waveforms. Holdoff time
means the waiting time for the trigger to be
ready for use again. During this time the
oscilloscope will not trigger until the Holdoff
is complete.
• Follow the normal signal synchronisation
procedure and select the edge, trigger
source and inclination in the trigger menu.
• Adjust the trigger level to make the
waveform display as stable as possible.
• Press the key in the horizontal MENU to display the horizontal menu.
• Adjust the multi-function control in the upper front panel. The hold-off time will
change accordingly until the waveform display is stable.
Functions Menu Setup Notes
Type Edge Set trigger mode to EDGE
Trigger source Alternate Set CH1 and Ch2 to alternate trigger
Inclination Rising Set trigger inclination as rising edge
Trigger mode Auto Set trigger mode to automatic
Trigger coupling AC Set trigger coupling mode to AC
Functions Menu Setup Notes
Type Edge Set trigger mode to EDGE
Trigger source Alternate Set CH1 and Ch2 to alternate trigger
Inclination Rising Set trigger inclination as rising edge
Trigger mode Auto Set trigger mode to automatic
Coupling
DC
AC
H/F reject
L/F reject
Intercept DC quantities.
Allow all quantities to pass.
Intercept high frequency quantities of the signal only allow low
frequency quantities to pass.
Intercept low frequency quantities of the signal only allow high
frequency quantities to pass.

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Trigger Source - Trigger can be obtained from various sources: Input channel (CH1 or
CH2), external trigger (EXT, EXT/5) or grid.
1. Input channel - the most common trigger source is input channel. The selected
trigger source can operate normally whether the input is displayed or not.
2. External trigger - this type of trigger source can trigger in a third channel while
acquiring data in two other channels. Both EXT and EXT/5 trigger sources use
external trigger signals from the EXT TRIG jack. EXT can use the signals directly.
You can use EXT within the trigger level range of -3V and +3V. EXT/5 divides the
trigger by 5. As a result trigger range is extended to -15V to +15V enabling the
oscilloscope to trigger at a large signal.
3. Grid - this trigger mode is suitable for observing signals related to the grid power
source eg: the correlation between lighting equipment and power source equipment
to achieve stable synchronisation.
Trigger Mode - determines the action of the oscilloscope when there is no trigger. There
are three trigger modes - auto, normal and single.
1. Auto Trigger - samples the waveform data when there is no trigger signal input.
The scan base is shown on the display. When the trigger signal is generated it
automatically turns to trigger scan for signal synchronisation.
Note: when the time base of the scan waveform is set to 50ms/div or slower, the auto
mode allows no trigger signal.
2. Normal Trigger - In this mode waveforms are only sampled when triggering
conditions are met. The system stops acquiring data and waits when there is no
trigger signal. When a trigger is generated, trigger scan occurs.
3. Single Trigger - In this mode press RUN button once and the oscilloscope will wait
for trigger. When one trigger is detected, it will sample and display the acquired
waveform, then stop.
Trigger coupling - determines which quantities of the signal are transmitted to the
trigger circuit. Coupling modes are DC, AC, low frequency reject and high frequency
reject.
1. DC - allowing all quantities to pass.
2. AC - intercepting DC quantities and attenuating signals under 10Hz.
3. Low Frequency Reject - Intercepting DC quantities and attenuating low frequency
quantities under 80kHz.
4. High Frequency Reject - Attenuating high frequency quantities over 80kHz.
Pre-Trigger/Delayed Trigger - data sampled before/after triggering. The trigger position
is typically set at the horizontal centre of the screen. You are able to view ve divisions
of pre-trigger and delayed trigger information. Use the horizontal position control to
adjust the horizontal shift of the waveform to see more pre-trigger information. By
observing pre-trigger data you can see the waveform before trigger occurs. You can
detect the glitch that occurs when the circuitry starts. Observing this data can help
identify the cause of this glitch.
OPERATION
Setting up the Sampling System
• The ACQUIRE button on the
control panel is the function key
for the sampling system.

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Functions Menu Setup Notes
Acquisition Mode
Sample
Peak detect
Average
Turn on the ordinary sampling mode
Turn on the peak detect mode
Set the average sampling and display the average number
of times
Average number of
times 2-256
Set the average number of times in multiples of 2 ie: 2, 4,
8, 16, 32, 64, 128, 256 To change the average number of
times use the multi-function control on the front panel.
Sampling mode Real time
Equivalent
Set sampling to real time
Set sampling to equivalent at a time base range of
5ns~100ns/div.
• By changing acquisition setup you can observe the
consequent changes in waveform display. If the
signal contains considerable noise, you will see this
waveform displays when average sampling is not
selected.
• When 32 time average sampling is selected you will
see this.
Note: Use Real Time Sampling to observe single
signals. In this mode the system makes full acquisition
to ll the memory. Maximum sampling rate is 500MS/s. At a setting of 50ns or faster,
the oscilloscope will automatically carry out interpolation ie: inserting a sampling point
between other sampling points.
Use Equivalent Sampling to observe high frequency cyclical signals. This is a
repeated sampling mode that allows detailed observation of repeated cyclical signals. In
the equivalent sampling mode, the horizontal resolution is 40ps higher than the real time
mode ie: 25GS/s equivalent.
Sampling Mode is when the oscilloscope reconstructs the waveform by sampling
signals at regular intervals.
To avoid mixed envelope, select Peak Detect. In this mode the oscilloscope identies
the maximum and minimum values of the input signals at each sampling interval and
use these values to display the waveform. In effect, the oscilloscope can acquire and
display narrow pulse which would otherwise be omitted in the sampling mode. Noise
seems to be more signicant in this mode.
Average Mode is when the oscilloscope acquires several waveforms and take the
average value to display the nal waveform. You can use this mode to reduce random
noise. To reduce random noise of the displayed signal, select average sampling and
increase the average number of times in multiples of 2 ie: selecting from 2 to 256.

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Setting up the Display System
• The DISPLAY button on the
control panel is the function key
for the display system.
Operating procedure
• Press STORAGE to go to the
type menu. There are three
types to select from:
1. WAVEFORM to go to the
waveform save menu.
2. SETUP to enter the setup save menu.
3. BITMAP to enter the position save menu
Note: this feature can only be recalled after connecting USB ram.
Functions Menu Setup Notes
Display type Vector
Dots
Sampling points are linked for display
Sampling points are directly displayed
Format YT
XY
Operating mode of the oscilloscope X-Y is the display mode
CH1 is X input CH2 is Y input.
Persist
Off
Innite
The waveform on the screen is refreshed at higher speed
The original waveform on the screen remains on display.
New data will be added continuously until this function is
disabled.
Contrast +, - Setting the waveform contrast
Display Type: Vector display lls the spaces between adjacent sample points. Dots
display only the sample points.
Refresh Rate: is the number of times the digital storage oscilloscope refreshes the
waveform display per second. The refreshing speed affects the capability to observe
signal movements.
Save and Recall: pressing the STORAGE button displays the setup menu from where
you can save or recall waveforms and setup documents stored in memory both internal
and in USB storage devices.
Functions Menu Setup Notes
Type Waveform Select the waveform save and recall menu
Signal source CH1
CH2
Select the waveform from CH1
Select the waveform from CH2
Save position 1~10
Set and select the position in which the waveform is saved in
the internal memory. Adjust using the multi-function control
Save -- Save the waveform
Disk DSO
USB
Select the internal memory
Select external USB memory
Depth Normal
Lengthy
Set normal saving depth of 250 dots
Set lengthy saving of 2.5k

19
Setting up Alternative Functions
• The UTILITY button on the
control panel is the function key
for alternative functions.
Functions Menu Setup Notes
Setup Select the front panel setup menu
Setup (save
position) 1~10
Maximum 10 front panel setups can be saved. Select with
the multi-function control on front panel
Save -- Save the setting
Recall -- Recall the setting
Functions Menu Setup Notes
Auto calibration Run
Cancel
Run auto calibration
Cancel calibration and return to previous menu
Recording
waveform
SEE TABLE
BELOW
Setup for recording waveform
Language
S Chinese
T Chinese
English
Select the language interface
Factory setup -- Setting up factory setup recall
Interface design
Design1
Design2
Design3
Design4
Setting up the interface design (colour display)
Two designs (mono display)
Functions Menu Setup Notes
Record CH1
CH2
Select CH1 as the recording signal source
Select CH2 as the recording signal source
Cancel Quit the current record menu and return to previous menu
n (F3)
Stop recording
u (F4)
Playback button - the system plays back and displays the
position reference in the lower RH corner. Use the multi-
function control to select the waveform to be displayed
repeatedly.
l (F5)
Record button - use to record. The position reference is
displayed in the bottom of the screen
Functions Menu Setup Notes
Bitmap Select the bitmap menu
Save position 1~10
Maximum 10 position data can be saved. Select with the
multi-function control on front panel
Recall Save graphic data

20
Setting up Auto Measurement
• The MEASURE button on the
control panel is the function key
for auto measurement.
Auto Calibration: you can correct measurement errors caused by environmental
changes with the auto calibration function. This process can be run selectively when
necessary. To make calibration more accurate, power on the oscilloscope and allow 20
minutes to warm up then press UTILITY button and follow the on screen instructions.
Choose your language: The Oscilloscope can be operated in several languages, press
UTILITY button and choose the desired language.
Automatic measurement of voltage parameters
• The DSO series oscilloscope can automatically measure the following voltage
parameters.
• Peak to peak value (Vpp) - the voltage value from the highest point to lowest point
of the waveform.
• Maximum value (Vmax) - the voltage value from the highest point to ground of the
waveform.
• Minimum value (Vmin) - the voltage value from the highest point to ground of the
waveform.
• Amplitude value (Vamp) - the voltage value from top to base of the waveform.
• Top value (Vtop) - the voltage value from the level top to ground of the waveform.
• Base value (Vbase) - the voltage value from the level base to ground of the
waveform.
• Overshoot - the ratio value of the difference between maximum value and top value
of the waveform to the amplitude value.
• Pre-shoot - the ratio value of the difference between minimum value and base value
of the waveform to the amplitude value.
• Average value - average amplitude of signals within 1 cycle.
• RMS value - the effective value. Energy generated by AC signal conversion during
one cycle with respect to the DC voltage that produces equivalent energy.
The oscilloscope is capable of measuring 20 waveform parameters.
• Press MEASURE to enter the parameter measurement display menu which has ve
zones for simultaneous display of measurement values assigned to function keys
F1 to F5 respectively. When selecting the measurement type of any zone, press the
corresponding function key to enter the type option menu.
• The measurement type option menu lets you choose voltage or time. You can enter
the voltage or time measurement by pressing F1~F5 for the corresponding type and
then return to the measurement display menu.
• Pressing F5 and select ALL PARAMETERS to show all measured parameters of
both voltage and time. Press F2 to select the channel (has to be enabled to take
measurements).
• Press F1 to return to the parameter measurement menu.