Tenma 72-9355 User manual

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Digital Storage Oscilloscope
Model No. 72-9355, 72-9360 & 72-9365

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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 600V 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 channels; vertical deection width range : 5mV/div – 50V/div.
• Automatic waveform and status conguration.
• Storage of waveforms, setups and interfaces.
• Screen copy function.
• Fine window extension; precise analysis of waveform details and overview.
• Automatic measurement of 27 waveform parameters.
• Cursor measurement function.
• Unique waveform recording, storage and replay function.
• USB interface that supports USB2.0.
• Bright colour/mono 5.7 inch LCD panel at 320 x 240 pixel aspect ratio.
• Built-in FFT.
• Multiple waveform math functions (including add, subtract, multiply and divide).
• Edge, video, pulse width, and alternate trigger functions.
• Multimeter function.
• USB drive system software upgrade.
• Multilingual menu displays.

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WHAT’S INCLUDED
• 2 x 1.2m, 1:1/10:1 probe (conforms with EN 61010-031:2002+A1:2008)
• Power cable
• User Manual
• 2 x current-to-voltage converter module
• Multimeter pen
• DC adaptor
CONTROLS AND CONNECTIONS
OPERATING PARAMETERS
• User-friendly front panel with clear labelling to enable access to all basic functions
for easy operation.
• 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.
Model Bandwidth Sampling Rate Display
72-9355 60MHz 250MS/s Colour
72-9360 100MHz 500MS/s Colour
72-9365 200MHz 1GS/s Colour
• The oscilloscope comes with a front panel with at-a-glance functions for easy
operation.
• There are function keys and a special function jog dial on the front panel.
• The row of 5 keys at the bottom of the display panel are menu operation keys
(designated as [F1] to [F5] from left to right). With these 5 keys you can set up
different options of the current menu.
• The other keys are function keys. You can use them to enter different function
menus or access particular functions directly.
• Apart from the waveform display zone, the
display panel also features other details about
the waveform and the unit’s control setup. These
are explained by their sequence numbers in the
above gure:
1. Trigger source status display is as follows:
A. Select signals of Channel A as the trigger
signal source.
B. Select signals of Channel B as the trigger
signal source.
AB. Select signals of Channels A and B as the
alternate trigger signal source
2. Trigger coupling mode display is as follows:
~ AC trigger coupling mode, i.e. only AC quantities
larger than 10Hz of the trigger signals can
pass the coupling capacitor. The DC% will be
intercepted. This is a general trigger coupling
mode.

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Power on the unit
• You can select from two power supply methods : internal battery power or external
DC adaptor power. Power supply voltage of the DC adaptor is grid voltage. After
connecting to power, start the self calibration process by pressing the [USER]
button then [F3]. This will ensure optimal performance.
Accessing signals
• Press UTILITY button then F1 and the screen will display DEFAULT SETUP.
• Connect the probe to the ChA input.
• Set the probe attenuation switch to 10X position.
Note You have to set the probe attenuation factor of the
oscilloscope. This factor changes the vertical range multiple to
ensure the measurement result correctly reects the amplitude of
the signal being tested.
Set the attenuation factor of the probe as follows: Select other
menu in Channel A then set probe ratio to 10X with the jog dial.
• Return
• K-return
• Normal
• Invert
OPERATION
AUTOSET WAVEFORM DISPLAY
• 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%.
• Connect the probe tip and ground clamp to the output terminal of the function signal
generator. Select a square wave of 1kHz output frequency and 3Vpp amplitude.
Press [AUTO] and you will see a 1kHZ/3Vpp square wave in the display in a few
seconds, as shown in Figure 1-5. Repeat steps 2 and 3 to check Channel B.
• Input A : On
Coupling : DC
Bandwidth limit ; Full bandwidth
Bias Voltage : Others

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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
• Pressing the key to adjust the vertical range (V/div) of the oscilloscope, you can
adjust the signal to a size best suited to screen.
• Pressing the key adjusts the position of the reference waveform so you can
adjust the position on the screen display.
Horizontal control
• Pressing the key to change the horizontal time base range setup. Range of
horizontal scanning rate is 5ns-50s/div (72-9360) in steps of 1-2-5.
• Pressing the key adjusts the position of the reference waveform so you can
adjust the position on the screen display. You can observe more pre-trigger
information.
The Trigger System :
• Press [TRIGGER] to adjust the trigger setup of the waveform.
mV
V
S nS

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INSTRUMENT SETUP
Vertical system setup
Channel A, Channel B and shifting signals vertically
• Each channel has its own menu. Set up each item for each channel individually.
Press the [A] or [B] function key and the system will display the operation menu for
Channel A or Channel B.
Resetting the Instrument
• To use factory setup, follow the steps below :
• After connecting to power press [POWER] to turn the oscilloscope on. When the
power-on screen appears, press and hold the [CLEAR/MENU] key to select factory
setup. When setup is done, this screen will appear.
Using the Jog Dial Function
• The jog dial is a multifunction control that enables
easy operation and control of various menus. The
example below illustrates the use of this dial.
Making menu selection with the jog dial
• Press [SCOPE]. The menu in the gure below
appears at the bottom of the screen.
Parameter measurement
Frequency counter
Off
• Press F3 to select the display menu.
• With the jog dial, select the display type. The selected
menu will appear bold. Turn the jog dial to make a
selection, then press the jog dial once to conrm. The
screen will then enter the next menu. If you wish to
change the format repeat the above steps. Otherwise
press the jog dial to close this menu.
• Press F5 to return to a previous selection option and reset that page.
Input A On
Off
Channel A on
Channel A off
Coupling DC
AC
Ground
AC and DC quantities of input signal is allowed to pass.
This mode is for observing DC or exchange signals with DC
quantities.
DC quantities of the input signal are intercepted. This
mode is for observing exchange signals with DC quantities
intercepted.
DC level of the channel input terminal upon equivalent
grounding is displayed.
Bandwidth
Limit
Full
Bandwidth
20MHz
The oscilloscope’s frequency bandwidth is full bandwidth.
Limit bandwidth to 20MHz to reduce display noise.
Bias Voltage Voltage
Reset to zero
Return
Adjust the channel bias voltage with the jog dial. When the
DC quantities of the signal being tested are much larger
than the amplitude of the AC signal, you can offset the DC
quantities with bias voltage. In this condition, you can observe
the amplied AC signal.
Reset the bias voltage to zero.
Go back to the Channel A menu

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Others Probe ratio 1X
10X
100X
1000X
Select one of the values based on the probe
attenuation factor to keep the reading of the
signal being measured correct.
Polarity Normal
Invert
Normal waveform display
Waveform is inverted
Setting channel coupling
• To apply a signal to Channel A. The signal being
tested is a sine signal that contains DC quantities.
• Press [A] to select Channel A. Then press [F1] to set
A input to “ON”.
• Next press [F2] to select DC coupling. Both DC and
AC quantities of the signal being tested and input to
Channel A can pass through.
• Press [F2] to select AC coupling. DC quantities of
the signal being tested and input to Channel A will be
intercepted. Only AC quantities can pass through.
• Press [F2] to select ground coupling. The channel
input is now set to equivalent ground. The channel
input level appears on screen.
Note: In this mode, although waveform is not displayed,
the input signal remains connected to the channel circuit.
Setting the channel bandwidth limit
• Applying a signal to Channel B. The signal being
tested is a signal stacked with high frequency
quantities.
• Press [B] to turn Channel B on. Next press [F3] to
set channel bandwidth to full bandwidth. The signal
being measured can pass through even if it contains
high frequency quantities.
• Press [F3] to set bandwidth limit to 20MHz. All high
frequency quantities higher than 20MHz in the signal
being tested will be limited.

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Setting bias voltage
• Bias voltage is suitable for observing the following signals:
• The input signal is made up of relatively high DC quantities and relatively low AC
quantities.
• The input AC signal is very low in frequency and contains DC quantities. AC mode
is unsuitable.
• Duty ratio of the signal is too small. Waveform details are hard to observe even in
AC mode.
Setting the probe rate
• 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.
• Apply this principle to other values to ensure the
voltage reading is correct.
• Press [A] to turn Channel A on, then press [F5].
Select “Others” and select 10X probe ratio with the
jog dial, as shown.
• Next press the jog dial once to conrm, then press
the jog dial again to close the menu.
The screen shows the setup and vertical range
display when the probe is set at 10:1.
Setting the waveform polarity
• Inverted waveform : This indicates the signal is 180°
inverted in relation to the channel ground level. The
example below shows the setup for signal inversion
and the display for inverted signal.
• Press [A] to turn Channel A on.
• Press [F5]. Select “Others” and select inverted
polarity, as shown in Figure 2-13.
• Press the jog dial once to conrm, then press the jog
dial again to close the menu.
• The screen shows the channel polarity inverted.
Changing the signal time base and horizontal shift
• Accelerate or decelerate the oscilloscope’s scanning
rate by pressing from 5ns/div~50s/div (72-9360).
Note: Minimum horizontal time base range of the 72-93xx Series varies from model to
model.
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Trigger System Setup
• Triggering decides when the oscilloscope collects data and display waveforms.
Once the trigger is correctly set up, it can transform unstable displays into
meaningful waveforms.
• When beginning to acquire data, the digital storage oscilloscope rst collects
sufcient data required for drawing a waveform on the left side of the trigger point.
• While waiting for the triggering condition, the oscilloscope will continue acquiring
sufcient data to draw a waveform on the right side of the trigger point. You can set
trigger functions with the trigger function key [TRIGGER].
Trigger : Key for the trigger function setup menu.
Trigger level : Trigger level is set to a signal voltage that matches the trigger point (by
turning the jog dial).
Trigger types : Edge, Video, Pulse.
Edge trigger : Trigger is set to occur when the signal is at the rising or falling edge. You
can set the trigger level to change the trigger point’s vertical position on the trigger edge,
i.e. the intersection point of the trigger level line and the signal edge on the screen.
Function Setup Explanation
Trigger Edge Set edge as the trigger type
Trigger
source
A
B
Alternate
Set Channel A as the signal source trigger signal.
Set Channel B as the signal source trigger signal.
A and B trigger their individual signals alternately
Trigger
Setup
Trigger
Mode
Auto
Normal
Single
Waveform is acquired even when no trigger condition is
detected.
Acquisition takes place only when trigger condition is met.
One waveform is acquired when one trigger is detected.
Acquisition then stops.
Trigger
Coupling
AC
DC
H/F Suppression
L/F Suppression
Allow AC and DC quantities of the input signal to pass.
Intercept DC quantities of the input signal.
Reject low frequency quantities below 80kHz of the signal.
Reject high frequency quantities above 80kHz of the signal
Slew
Rate
Rise
Fall
Set to trigger at the signal’s rising edge.
Set to trigger at the signal’s falling edge.
Holdoff 40ns – 1.5s Adjust holdoff time.
Adjusting Hold-off Time
• You can adjust the hold-off time to observe complicated waveforms (e.g. pulse
string series). Hold-off time means adjusting the data acquisition cycle of the
digital storage oscilloscope. It is an exact multiple of the cycle of the complicated
waveform being tested, thus synchronization is possible.
For example: if the signals being tested are a group of wave signals, apply them to
Channel A then press [TRIGGER] to select edge trigger mode.
Next press [F5] to activate hold-off adjustment and adjust
hold-off time with the jog dial. Hold-off time will change
accordingly until waveform display is stable, as shown.
Note: Hold-off time is usually slightly shorter than
the “large cycle” time. When observing the RS-232
communication signal, it is easier to achieve stable
synchronization of hold-off time is slightly shorter than the
starting edge time of every set of data.

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Functions Menu Setup Notes
Trigger Video Set video trigger as trigger type.
Trigger source
A
B
Alternate
Set A as the signal source trigger signal.
Set B as the signal source trigger signal.
A and B trigger their individual signals respectively.
Standard trigger PAL
NTSC
Suitable for PAL video signals.
Suitable for NTSC video signals
Synchronisation
All lines
Specied lines
Odd eld
Even eld
Set the TV line to synchronize with trigger.
Set synchronized trigger on the specied line and
adjust with the jog dial.
Set the video odd eld to synchronized trigger.
Set the video even eld to synchronized trigger.
Pulse Trigger
• When the pulse width of the trigger signal reaches a preset trigger condition, trigger
occurs.
• Pulse trigger means determining the triggering time based on the pulse width. You
can acquire abnormal pulse by setting the pulse width condition.
Video trigger : Carry out eld or line trigger with NTSC or PAL standard video signals.
Function Setup Explanation
Trigger Pulse Set edge as the trigger type.
Trigger
source
A
B
Alternate
Set Channel A as the signal source trigger signal.
Set Channel B as the signal source trigger signal.
A and B trigger their individual signals alternately.
Trigger
setup
Trigger
mode
Auto
Normal
Single
Set to acquire waveform only if no trigger is detected.
Set to acquire waveform only if trigger condition is satised.
Set to acquire one waveform when one trigger is detected,
then stop.
Trigger
coupling
AC
DC
H/F Reject
L/F Reject
Intercept AC and DC quantities of the input signal.
Intercept DC quantities of the input signal.
Suppress low frequency quantities below 80kHz of the signal.
Suppress high frequency quantities above 80kHz of the signal.
Pulse
width 40ns – 6.40s Set pulse width with the jog dial.
Pulse
width
setup
Pulse width
condition
=
<
>
Trigger occurs when pulse width equals to the set value.
Trigger occurs when pulse width is smaller than the set value.
Trigger occurs when pulse width is larger than the set value.
Pulse width
polarity
Positive
Negative
Set the positive pulse width as the trigger signal.
Set the negative pulse width as the trigger signal.
• When PAL is selected for standard format and
synchronization mode is “specied line”, you will see
a screen display as shown.