Additional Information

Model	Channels	Bandwidth	Sample Rate
GAO-MSO-101A	2	200 MHz	Max. 1 GS / s
GAO-MSO-101B	2	100 MHz	Max. 1 GS / s
GAO-MSO-101C	2	60 MHz	Max. 1 GS / s

Getting Started Guide

Installation

To keep proper ventilation of the oscilloscope in operation, leave a space of more than 5cm away from the top and the two sides of the product.
Power Supply
Use a power supply that delivers 90 VRMS to 240 VRMS, 45 Hz to 440 Hz.
Power Cord
Use only power cords designed for this product.

Functional Check
Follow the steps below to perform a quick functional check to your oscilloscope.
Power on the oscilloscope
Plug in the oscilloscope and press the ON/OFF button. Then push the DEFAULT SETUP button. The default Probe option attenuation setting is 10 X.

Connect the oscilloscope

Set the switch on the probe to 10X and connect the probe to Channel 1 on the oscilloscope. First, align the slot in the probe connector with the protuberance on the CH1 BNC and push to connect; then, turn to right to lock the probe in place; after that, connect the probe tip and reference lead to the PROBE COMP connectors. There is a mark on the panel: Probe COMP ~5 V@1 KHz.

Observe the waveform

 Press the AUTOSET button and you should see within a few seconds a square wave of about 5 V peak-to-peak at 1 kHz in the display. Press the CH1 MENU button twice to remove Channel 1. Push the CH2 MENU button and repeat Step 2 and Step 3 to observe Channel 2.

Probe Examinations

 Safety

When using the probe, keep your fingers behind the guard on the probe body to avoid electric shock. Do not touch metallic portions of the probe head while it is connected to a voltage source. Connect the probe to the oscilloscope and connect the ground terminal to ground before you start any measurements.

Use of Probe Check Wizard

Every time you connect a probe to an input channel, you should use the probe check wizard to verify that this probe is operating correctly. There are two ways to do this:

1. Use the vertical menu (for example, push the CH1 MENU button) to set the Probe option attenuation factor.
2. Press the PROBE CHECK button to use the Probe Check Wizard and configure the probe option attenuation factor properly following menu prompts.

Manual Probe Compensation

 Upon the first connection of a probe and an input channel, you should manually perform this adjustment to match the probe to the input channel. Uncompensated or miss-compensated probes may lead to errors or faults in measurement. To adjust the probe compensation, follow the steps below.

1. Set the Probe option attenuation in the channel menu to 10 X. Set the switch on the probe to 10 X and connect the probe to Channel 1 on the oscilloscope. If you use the probe hook-tip, ensure it is firmly inserted onto the probe. Attach the probe tip to the PROBE COMP ~5 V@1 KHz connector and the reference lead to the PROBE COMP Ground connector. Display the channel and then press the AUTOSET button.
2. Check the shape of the displayed waveform.
   
3. If necessary, use a non-metallic screwdriver to adjust the variable capacity of your probe until the shape of the waveform turns to be the same as the above figure. Repeat this step as necessary. See the figure below for the way of adjustment.
   

Probe Attenuation Setting

Probes are of various attenuation factors which affect the vertical scale of the signal. The Probe Check function is used to verify if the Probe attenuation option matches the attenuation of the probe.As an alternative method to Probe Check, you can push a vertical menu button (such as the CH 1 MENU button) and select the Probe option that matches the attenuation factor of your probe.Make sure that the Attenuation switch on the probe matches the Probe option in the oscilloscope. Switch settings are 1 X and 10 X.When the Attenuation switch is set to 1 X, the probe limits the bandwidth of the oscilloscope to 6 MHz. To use the full bandwidth of the oscilloscope, be sure to set the switch to 10 X.

Self Calibration

 The self-calibration routine helps optimize the oscilloscope signal path for maximum measurement accuracy. You can run the routine at any time but should always run it if the ambient temperature changes by 41 °F (5 ℃) or more. For a more accurate calibration, please power on the oscilloscope and wait for 20 minutes until it has adequately warmed up. To compensate the signal path, disconnect any probes or cables from the front-panel input connectors. Then, push the UTILITY button, select the Do Self Cal option and follow the directions on the screen.

Logic Analyzer Flat Input Cable
GAO-MSO-101 series has logic analyzer function, and its logic signal input port is shown as follows:

The flat terminal connection cable is shown as below.

1. Digital Input Terminal The total of digital signal input terminals is 18, arranged as two rows, GND, D0-D7 and GND, D8-D15.
2. Flat Cable Plug the flat cable into the logic signal input port in accordance with the sequence of the input port. Note: When connect with device, please insert input terminals gently to avoid damaging cable socket or other components.

Main Feature Description

 Oscilloscope Setup

While operating the oscilloscope, you may often use three features: Auto-set, saving a setup and recalling a setup. Hereinafter they are introduced one by one.

Auto-set: This function can be used to adjust the horizontal and vertical scales of the oscilloscope automatically and set the trigger coupling, type, position, slope, level and mode, etc., to acquire a stable waveform display.

Saving a Setup: By default, the oscilloscope will save the setup each time before being closed, and automatically recall the setup once being turned on.
(Note: If you modify the setup, please wait for more than 5 seconds before turning off the oscilloscope to ensure the proper storage of new settings.) You can save 10 settings permanently in the oscilloscope and reset them as necessary.

Recalling a Setup: The oscilloscope can recall any of your saved setups and the default factory setup.

Default Setup: The oscilloscope is pre-set for normal operations when it is shipped from the factory. This is the default setup. You may recall this setup at any time for your requirements.

Trigger

The trigger determines when the oscilloscope begins to acquire data and display a waveform. Once a trigger is properly set up, the oscilloscope can convert unstable displays or blank screens to meaningful waveforms. Here introduce some basic

Trigger Source:

The trigger can be generated with multiple sources. The most common one is the input channel (alternative between CH1 and CH2). Whether the input signal is displayed or not, it can trigger normal operations. Also the trigger source can be any signal connected to an external trigger channel or the AC power line (only for Edge triggers). The source with the AC power line shows the frequency relationship between the signal and the AC commercial power.

Trigger Type:

The oscilloscope has six types of triggers: Edge, Video, Pulse Width, Slope, Overtime and Swap.

• Edge Trigger uses the analog or digital test circuits for triggering. It happens when the input trigger source crosses a specified level in a specified direction.
• Video Trigger performs a field or line trigger through standard video signals.
• Pulse Width Trigger can trigger normal or abnormal pulses that meet trigger conditions.
• Slope Trigger uses the rise and fall times on the edge of signal for triggering.
• Overtime Trigger happens after the edge of signal reaches the set time.
• Swap Trigger, as a feature of analog oscilloscopes, gives stable displays of signals at two different frequencies. Mainly it uses a specific frequency to switch between two analog channels CH1 and CH2 so that the channels will generate swap trigger signals through the trigger circuitry.

Trigger Mode: You can select the Auto or Normal mode to define how the oscilloscope acquires data when it does not detect a trigger condition.
Auto Mode performs the acquisition freely in absence of valid trigger. It allows the generation of un-triggered waveforms with the time base set to 80ms/div or slower.
Normal Mode updates the displayed waveforms only when the oscilloscope detects a valid trigger condition. Before this update, the oscilloscope still displays the old waveforms. This mode shall be used when you want to only view the effectively triggered waveforms. In this mode, the oscilloscope displays waveforms only after the first trigger. To perform a single sequence acquisition, push the SINGLE SEQ button.
Trigger Coupling: Trigger Coupling determines which part of the signal will be delivered to the trigger circuit. This can help to obtain a stable display of the waveform. To use trigger coupling, push the TRIG MENU button, select an Edge or Pulse trigger, and then select a Coupling option.
Trigger Position: The horizontal position control establishes the time between the trigger position and the screen center.
Slope and Level: The Slope and Level controls help to define the trigger. The Slope option determines whether the trigger point is on the rising or falling edge of a signal. To perform the trigger slope control, press the TRIG MENU button, select an Edge trigger, and use the Slope button to select rising or falling. The TRIGGER LEVEL knob controls the trigger point is on which position of the edge.

Data Acquisition

 When you acquire an analog signal, the oscilloscope will convert it into a digital one. There are two kinds of acquisition: Real-time acquisition and Equivalent acquisition. The real-time acquisition has three modes: Normal, Peak Detect, and Average. The acquisition rate is affected by the setting of time base.

Normal: In this acquisition mode, the oscilloscope samples the signal in evenly spaced intervals to establish the waveform. This mode accurately represents signals in most time. However, it does not acquire rapid variations in the analog signal that may occur between two samples, which can result in aliasing and may cause narrow pulses to be missed. In such cases, you should use the Peak Detect mode to acquire data.

Peak Detect: In this acquisition mode, the oscilloscope gets the maximum and minimum values of the input signal over each sample interval and uses these values to display the waveform. In this way, the oscilloscope can acquire and display those narrow pulses that may have otherwise been missed in Normal mode. However, noise will appear to be higher in this mode.

Average: In this acquisition mode, the oscilloscope acquires several waveforms, averages them, and displays the resulting waveform. You can use this mode to reduce random noise.

Equivalent Acquisition: This kind of acquisition can be utilized for periodic signals. In case the acquisition rate is too low when using the real-time acquisition, the oscilloscope will use a fixed rate to acquire data with a stationary tiny delay after each acquisition of a frame of data. After repeating this acquisition for N times, the oscilloscope will arrange the acquired N frames of data by time to make up a new frame of data. Then the waveform can be recovered. The number of times N is related to the equivalent acquisition rate.

Time Base: The oscilloscope digitizes waveforms by acquiring the value of an input signal at discrete points. The time base helps to control how often the values are digitized. Use the SEC/DIV knob to adjust the time base to a horizontal scale that suits your purpose.

Waveform Scaling and Positioning

 The display of waveforms on the screen can be changed by adjusting their scale and position. Once the scale changes, the waveform display will increase or decrease in size. Once the position changes, the waveform will move up, down, right, or left. The channel reference indicator (located on the left of the gratitude) identifies each waveform on the screen. It points to the ground level of the waveform record.

Vertical Scale and Position: The vertical position of a waveform can be changed by moving it up and down on the screen. To compare data, you may align a waveform over another. When you push the VOLTS/DIV button to change the vertical scale of a waveform, the waveform display will contract or expand vertically to the ground level.

Horizontal Scale and Position: Pre-trigger Information

 You can adjust the HORIZONTAL POSITION control to view waveform data before the trigger, after the trigger, or some of each. When you change the horizontal position of a waveform, you are actually changing the time between the trigger position and the screen center.

For example, if you want to find out the cause of a glitch in your test circuit, you should trigger on the glitch and make the pre-trigger period long enough to capture data before the glitch. Then you can analyse the pre-trigger data and perhaps find the cause. You are allowed to change the horizontal scale of all the waveforms by turning the SEC/DIV knob.

For example, you may want to see just one cycle of a waveform to measure the overshoot on its rising edge. The oscilloscope shows the horizontal scale as time per division in the scale readout. Since all active wav’] performs use the same time base, the oscilloscope only displays one value for all the active channels.

Waveform Measurement

The oscilloscope displays graphs of voltage versus time and can help to measure the displayed waveform. There are several ways to take measurements, using the graticule, the cursors or performing an automatic measurement.

Graticule: This method allows you to make a quick, visual estimate and take a simple measurement through the graticule divisions and the scale factor. For example, you can take simple measurements by counting the major and minor graticule divisions involved and multiplying by the scale factor. If you counted 6 major vertical graticule divisions between the minimum and maximum values of a waveform and knew you had a scale factor of 50mV/division, you could easily calculate your peak-to-peak voltage as follows:

  6 divisions x 50 mV/division = 300 mV.

Cursor: This method allows you to take measurements by moving the cursors. Cursors always appear in pairs and the displayed readouts are just their measured values. There are two kinds of cursors: Amplitude Cursor and Time Cursor. The amplitude cursor appears as a horizontal broken line, measuring the vertical parameters. The time cursor appears as a vertical broken line, measuring the horizontal parameters.When using cursors, please make sure to set the Source to the waveform that you want to measure on the screen. To use cursors, push the CURSOR button.

Automatic Measurement: The oscilloscope performs all the calculations automatically in this mode. As this measurement uses the waveform record points, it is more precise than the graticule and cursor measurements. Automatic measurements show the measurement results by readouts which are periodically updated with the new data acquired by the oscilloscope.

Basic Operation

The front panel of the oscilloscope is divided into several functional areas. In this chapter we will give a quick overview of all control buttons and knobs on the front panel as well as the displayed information on the screen and relative testing operations. The figure below illustrates the front panel of the digital oscilloscope.

Display Area

Display Format

Gray indicates auto persistence; Green means persistence display is enabled. When the icon is set to green, the time for persistence display will be shown behind it.

Acquisition Mode: Normal, Peak Detect or Average

Trigger Status:

The oscilloscope is acquiring pretriggered data.
  All pretriggered data have been acquired and the oscilloscope is ready to accept a trigger
T   The oscilloscope has detected a trigger and is acquiring the post trigger information
 The oscilloscope works in auto mode and is acquiring waveforms in the absence of triggers.
 The oscilloscope is acquiring and displaying waveform data continuously in scan mode
  The oscilloscope has stopped acquiring waveform data
   S  The oscilloscope has finished a single sequence acquisition

Tool Icon:

: If this icon lights up, it means the keyboard of the oscilloscope is locked by the host computer via USB control.
If this icon lights up, it means the USB disk has been connected.
This icon lights up only when the USB slave interface is connected with the computer.

Readout shows main time base setting.
Main Time Base Window
Display of window’s position in data memory and data length.
Window Time Base
Operating Menu shows different information for different function keys.
Readout shows frequency count.
Readout points out horizontal waveform position
Trigger Type:

Edge trigger on the rising edge.
Edge trigger on the falling edge.
Video trigger with line synchronization.
Video trigger with field synchronization.
Pulse Width trigger, positive polarity.
Pulse Width trigger, negative polarity.

X-Y Format

The XY format is used to analyse phase differences, such as those represented by Lissajous patterns. The format plots the voltage on CH1 against the voltage on CH2, where CH1 is the horizontal axis and CH2 is the vertical axis. The oscilloscope uses the un-triggered Normal acquisition mode and displays data as dots. The sampling rate is fixed at 1 MS/s.The oscilloscope can acquire waveforms in YT format at any sampling rate. You may view the same waveform in XY format. To perform this operation, stop the acquisition and change the display format to XY.

Horizontal Controls

Use the horizontal controls to change the horizontal scale and position of waveforms. The horizontal position readout shows the time represented by the center of the screen, using the trigger time as zero. When you change the horizontal scale, the waveform will expand or contract to the screen center. The readout near the upper right of the screen shows the current horizontal position in second. M represents ‘Main Time Base’, and W indicates ‘Window Time Base’. The oscilloscope also has an arrow icon at the top of the graticule to indicate the horizontal position.

HORIZONTAL POSITION Knob: Used to control the trigger position against the screen center. Push this button to reset the trigger point back to the screen center.Used to set the horizontal position as zero.

Each option in HORIZ MENU is described as follows:

• Window Control: Major and Minor Window
• Mark: Right arrow, Left arrow, Set/Clear, Clear All
• Hold Off: None
• AutoPlay: None

Single-window Mode

Dual-window Mode (Full Screen)

SEC/DIV Knob: Used to change the horizontal time scale so as to magnify or compress the waveform horizontally. If the waveform acquisition is stopped (by using the RUN/STOP or SINGLE SEQ button), the SEC/DIV control will expand or compress the waveform. In dual-window mode, push this knob to select major or minor window. When the major window is selected, this knob provides the same functions as it provides in single-mode window. When the minor window is selected, turn this knob to scale the waveform whose magnification is up to 1000.

Notes: Major Window Minor Window (Expanded Window) Location of expanded window data in memory Multi-Functional Knob

1. For more information of the trigger hold-off, see Section Trigger Controls.
2. In single-window mode, press F0 to hide or show the menus on the right side. The dual-window mode does not support the menu hiding function.

Scan Mode Display (Roll Mode)

With the SEC/DIV control set to 80ms/div or slower and the trigger mode set to Auto, the oscilloscope works in the scan acquisition mode. In this mode, the waveform display is updated from left to right without any trigger or horizontal position control.

Vertical Controls

Vertical controls can be used to display and remove waveforms, adjust vertical scale and position, set input parameters and perform math calculations. Each channel has a separate vertical menu to set. See below for menu description.

VERTICAL POSITION Knob:

Move the channel waveform up and down on the screen. In dual-window mode, move the waveforms in both windows at the same time in a same direction. Push this knob to return waveforms to the vertical center position on the screen. Two channels correspond to two knobs.

Ground Coupling

Used to display a zero-volt waveform. Internally, the channel input is connected with a zero-volt reference level.

Fine Resolution

In the fine resolution setting, the vertical scale readout displays the actual VOLTS/DIV setting. The vertical scale changes only after you adjust the VOLTS/DIV control and set to coarse.

Remove Waveform Display

To remove a waveform from the screen, first push the menu button to display the vertical menu, then push again to remove the waveform. A channel waveform which is unnecessary to be displayed can be used as a trigger source or for math operations.

VOLTS/DIV Knob

Control the oscilloscope to magnify or attenuate the source signal of the channel waveform. The vertical size of the display on the screen will change (increase or decrease) to the ground level. Also you may use this knob to switch between coarse and fine.

Math FFT

You can use the Math FFT mode to convert a time-domain (YT) signal into its frequency components (spectrum), and to observe the following types of signals:

• Analyse harmonics in power cords;
• Measure harmonic content and distortion in systems
• Characterize noise in DC power supplies
• Test impulse response of filters and systems
• Analyse vibration.

To use the Math FFT mode, perform the following tasks:

•  Set the source (time-domain) waveform;
• Display the FFT spectrum;
•  Choose a type of FFT window;
•  Adjust the sample rate to display the fundamental frequency and harmonics without aliasing;
•  Use zoom controls to magnify the spectrum;
• Use cursors to measure the spectrum.

Setting Time-domain Waveform

It is necessary to set the time-domain (YT) waveform before using the FFT mode. Follow the steps below.

1. Push the AUTOSET button to display a YT waveform.
2. Turn the VERTICAL POSITION knob to vertically move the YT waveform to the center (zero division) so as to ensure the FFT will display a true DC value.
3. Turn the HORIZONTAL POSITION knob to position the part of the YT waveform to be analysed in the center eight divisions of the screen. The oscilloscope uses the 2048 center points of the time-domain waveform to calculate the FFT spectrum.
4. Turn the VOLTS/DIV knob to ensure the entire waveform remains on the screen. If the entire waveform is invisible, the oscilloscope may display wrong FFT results by adding high-frequency components.
5. Turn the SEC/DIV knob to provide the resolution you need in the FFT spectrum.
6. If possible, set the oscilloscope to display multiple signal cycles. If you turn the SEC/DIV knob to select a faster setting (fewer cycles), the FFT spectrum will display a larger frequency range and reduce the possibility of FFT aliasing.

To set the FFT display, follow the steps below.

1. Push the MATH MENU button
2. Set the Operation option to FFT
3.  Select the Math FFT Source channel. In many situations, the oscilloscope can also generate a useful FFT spectrum despite the YT waveform not being triggered. This is especially true if the signal is periodic or random (such as noise).

Note: You should trigger and position transient or burst waveforms as close as possible to the screen center.

Nyquist Frequency 

The highest frequency that any real-time digital oscilloscope can measure without errors is half of the sample rate, which is called the Nyquist frequency. Frequency information beyond the Nyquist frequency is under sampled which brings about the FFT aliasing. The math function can convert the center 2048 points of the time-domain waveform to an FFT spectrum. The resulting FFT spectrum contains 1024 points from DC (0Hz) to the Nyquist frequency. Usually, the screen compresses the FFT spectrum horizontally to 250 points, but you can use the FFT Zoom function to expand the FFT spectrum so that you can clearly view the frequency components at each of the 1024 data points in the FFT spectrum.

Note: The oscilloscope’s vertical response is a little bit larger than its bandwidth (60 MHz; or 20 MHz when the Bandwidth Limit option is set to Limited). Therefore, the FFT spectrum can display valid frequency information above the oscilloscope bandwidth. However, the amplitude information near or above the bandwidth will not be accurate.

Displaying FFT Spectrum

Push the MATH MENU button to display the Math menu. Use the options to select the Source channel, the Window algorithm and the FFT Zoom factor. Only one FFT spectrum can be displayed at a time.

1. Displaying FFT Spectrum
2. Push the MATH MENU button to display the Math menu. Use the options to select the Source channel, the Window algorithm and the FFT Zoom factor. Only one FFT spectrum can be displayed at a time.
3. Frequency at the center graticule line
4.  Vertical scale in dB per division (0 dB=1 VRMS)
5. Horizontal scale in frequency per division
6.  Sample rate in number of samples per second
7.  FFT window type

Selecting FFT Window

Using windows can eliminate the spectral leakage in the FFT spectrum. The FFT algorithm assumes that the YT waveform repeats all the time. When the number of cycles is integral (1, 2, 3 …), the YT waveform starts and ends at the same amplitude and there are no discontinuities in the signal shape.

If the number of cycles is non-integral, the YT waveform starts and ends at different amplitudes and transitions between the start and end points will cause discontinuities in the signal that introduces high-frequency transients.

Applying a window to the YT waveform changes the waveform so that the start and stop values are close to each other, which reduces the discontinuities.

The Math FFT function has three FFT Window options. There is a trade-off between frequency resolution and amplitude accuracy for each type of window. You shall determine which one to choose according to the object you want to measure and the source signal characteristics.

Window	Measurement	Characteristics
Hanning amplitude accuracy than Flattop	Periodic Waveform	Better frequency, poorer amplitude accuracy than Flattop
Flattop	Periodic Waveform	Better amplitude, poorer frequency accuracy than Hanning
Rectangular	Pulse or Transient Waveform	Special-purpose window applicable to discontinuous waveforms. This is actually the same as no windows.

FFT Aliasing

 Problems occur when the time-domain waveform acquired by the oscilloscope contains frequency components higher than the Nyquist frequency. The frequency components above the Nyquist frequency will be under sampled and displayed as lower frequency components that ‘fold back’ from the Nyquist frequency. These erroneous components are called aliases.

To eliminate aliases, use the following methods.

• Turn the SEC/DIV knob to set a faster sample rate. Because the Nyquist frequency increases as you increase the sample rate, the aliased frequency components will be displayed correct. If too many frequency components appear on the screen, you may use the FFT Zoom option to magnify the FFT spectrum.
• If there is no need to observe the frequency components above 20 MHz, set the Bandwidth Limit option to Limited.
• Filter the signal input from outside and limit the bandwidth of the source waveform to lower than the Nyquist frequency.
• Identify and ignore the aliased frequencies.
• Use zoom controls and cursors to magnify and measure the FFT spectrum.

Magnifying and Positioning FFT Spectrum

 You may scale the FFT spectrum and use cursors to measure it through the FFT Zoom option which enables the horizontal magnification. To vertically magnify the spectrum, use the vertical controls.

Horizontal Zoom and Position

 You can use the FFT Zoom option to magnify the FFT spectrum horizontally without changing the sample rate. The available zoom factors are X1(default), X2, X5 and X10. When the zoom factor is set to X1 and the waveform is located at the center graticule, the left graticule line is at 0Hz and the right is at the Nyquist frequency.

You magnify the FFT spectrum to the center graticule line when you change the zoom factor. That is, the axis for horizontal magnification is the center graticule line. Turn the Horizontal Position knob clockwise to move the FFT spectrum to the right. Push the SET TO ZERO button to position the center spectrum at the center of the graticule.

Vertical Zoom and Position

 When the FFT spectrum is being displayed, the channel vertical knobs become the zoom and position controls corresponding to their respective channels. The VOLTS/DIV knob provides the following zoom factors: X1(default), X2, X5 and X10. The FFT spectrum is magnified vertically to the marker M (math waveform reference point on the left edge of the screen). Turn the VERTICAL POSITION knob clockwise to move up the spectrum.

Using Cursors to Measure FFT Spectrum

 You may use cursors to take two measurements on the FFT spectrum: amplitude (in dB) and frequency (in Hz). Amplitude is referenced to 0 db that equals 1 VRMS here. You may use cursors to measure at any zoom factor.

Push the CURSOR button, choose the Source option and then select Math. Press the Type option button to select between Amplitude and Frequency. Click the SELECT CURSOR option to choose a cursor. Then use the V0 knobs to move Cursor S and Cursor E. Use the horizontal cursor to measure the amplitude and the vertical cursor to measure the frequency. Now the display at the DELTA menu is just the measured value, and the values at Cursor S and Cursor E.

Delta is the absolute value of Cursor S minus Cursor E.

Trigger Controls

 The trigger can be defined through the Trigger Menu and front-panel controls. There are six types of trigger: Edge, Video, Pulse Width, Swap, Slope and Overtime. Refer to the following tables to find a different set of options for each type of trigger.

1. Level It sets the amplitude level the signal must cross to cause an acquisition when using the Edge or Pulse Width trigger.
2. Set to 50 % the trigger level is set to the vertical midpoint between the peaks of the trigger signal.
3. Force Trigger It is used to complete an acquisition regardless of an adequate trigger signal. This button becomes useless if the acquisition is already stopped.
4. TRIG MENU Push this button to display trigger menus. The edge trigger is in common use. See the table below for details.

Options:

• Edge Video Pulse Slope Swap Overtime
• Source: CH1 CH2 EXT EXT/5 AC Line
• Mode: Auto
• Coupling: AC DC  HF Reject  LF Reject

NOTE: Trigger coupling only affects the signal passed through the trigger system. It does not affect the bandwidth or coupling of the signal displayed on the screen.

Pulse Width Trigger

You can use it to trigger on aberrant pulses.

• Pulse: With Pulse highlighted, the trigger occurs on pulses that meet the trigger condition (defined by the Source, When and Set Pulse Width options).
• Source: CH1, CH2, EXT, EXT5
• When: =, ≠, <, >
• Set pulse width: 20ns to 10.0sec
• Polarity: Positive, Negative
• Mode: Auto, Normal
• Coupling: AC, DC, HF Reject, LF Reject

Trigger When: The pulse width of the source must be ≥5 ns so that the oscilloscope can detect the pulse.

＝, ≠: Within a ±5 % tolerance, triggers the oscilloscope when the signal pulse width is equal to or not equal to the specified pulse width.

＜, ＞: Triggers the oscilloscope when the source signal pulse width is less than or greater than the specified pulse width.

Slope Trigger: Judges trigger according to the time for rising or falling, more flexible and accurate than the Edge trigger.

Options:

• Source: CH1 CH2 EXT EXT5
• Slope: Rising Falling
• Mode: Auto, Normal
• Coupling: AC, DC, Noise Reject, HF Reject, LF Reject
• Vertical: V1, V2
• When: = ≠ < >
• Time: 20ns to 10.0sec

Swap Trigger: As a feature of analog oscilloscopes, it gives stable displays of signals at two different frequencies. Mainly it uses a specific frequency to switch between two analog channels CH1 and CH2 so that the channels will generate swap trigger signals through the trigger circuitry.

Options:

• Mode: Auto, Normal
• Channel CH1, CH2

Sub Menu:

• Type: Edge
• Slope: Rising, Falling
• Coupling: AC, DC, HF Reject, LF Reject
• Type: Video
• Polarity: Normal, Inverted
• Standard: NTSC, PAL/SECAM
• Sync: All Lines, Line Number, Odd Field, Even Field, All Fields
• Type: Pulse
• Polarity: Positive, Negative
• When: = ≠ < >
• Set Pulse Width: Pulse Width
• Coupling: AC, DC, Noise Reject, HF Reject, LF Reject
• Type: Slope
• Slope: Rising, Falling
• Mode: Auto, Normal
• Coupling: AC, DC, Noise Reject, HF Reject, LF Reject

Next Page:

• Vertical: V1, V2
• When: = ≠ < >
• Time: 20ns to 10.0sec

Overtime Trigger: In Pulse Width trigger, you may sometimes be puzzled with the long time for trigger, as you do not need a complete pulse width to trigger the oscilloscope, but want the trigger occurs just upon the overtime point. This is called Overtime Trigger.

• Type: OT
• Source: CH1, CH2
• Mode: Auto, Normal
• Polarity: Positive, Negative
• Overtime: t
• Coupling: AC, DC, HC Reject, LF Reject

Hold-off: To use Trigger Hold-off, push the HORIZONTAL Menu button and set the Hold-off Time option by pressing F4. The Trigger Hold-off function can be used to generate a stable display of complex waveforms (such as pulse trains). Hold-off is the time between when the oscilloscope detects one trigger and when it is ready to detect another. During the hold-off time, the oscilloscope will not trigger. For a pulse train, the hold-off time can be adjusted to let the oscilloscope trigger only on the first pulse in the train.

 

 Menu and Option Buttons

As shown below, these six buttons at the top of the front panel are used mainly to recall relative setup menu.

SAVE/RECALL: Displays the Save/Recall menu for setups and waveforms.

MEASURE: Displays the Measure menu.

ACQUIRE: Displays the Acquire menu.

UTIILITY: Displays the Utility menu.

CURSOR: Displays the Cursor menu.

DISPLAY: Displays the Display menu.

SAVE / RECALL

Press the SAVE / RECALL button to save or recall oscilloscope setups or waveforms. The first page shows the following menu.

• Source: CH1, CH2, OFF, MATH OFF
• REF: RefA, RefB
• Operation: Save, Ref on Ref off

Press ‘Next Page’ to recall the following menu Press ‘Next Page’ to recall the following menu

• Operation Source: Flash memory , USB Disk
• Memory: 0-9
• Operation: Save, Recall

See below for waveform menus.

Note: The oscilloscope will save the current settings if you wait 5 seconds after the last modification, and it will recall these settings the next time you power on the oscilloscope.

MEASURE

Push the MEASURE button to perform auto measurements. There are 11 types of measurements and up to 8 can be displayed at a time. Turn the V0 knob to select an unspecified option. Press V0 or F6 when the red arrow icon stops on it. Then the following menu appears. Options:

• Source: Select the measure source
• Memory: 0 to 9, Period, Mean, Pk-Pk, Cyc RMS, Min, Max, Rise Time, Fall Time, Positive Width, Negative Width, OFF

Use the knob V0 or the functional keys F3, F4 to select the type of measurement.

Taking Measurements:

For a single waveform (or a waveform divided among multiple waveforms), up to 8 automatic measurements can be displayed at a time. The waveform channel must stay in an ‘ON’ (displayed) state to facilitate the measurement. The automatic measurement cannot be performed on reference or math waveforms, or in XY or Scan mode.

ACQUIRE

Push the ACQUIRE button to set the acquisition parameter. Option are as follows:

• Category: Real Time, Equ-Time
• Mode (Real Time): Normal, Peak, Detect, Average
• Averages (Real Time): 4, 16, 64, 128
• Memory Depth (Real Time): 4K, 40K, 512K, 1M

Normal: For the oscilloscope model with the bandwidth of 100 MHz, the maximum sample rate is 1 GS/s. For time base with insufficient sample rate, you may use the Sine Interpolation Algorithm to interpolate points between sampled points to produce a complete waveform record (4 K by default).

Peak Detect:

 Use this mode to detect glitches within 10 ns and to limit the possibility of aliasing. This mode is valid at the SEC/DIV setting of 4 µs/div or slower. Once you set the SEC/DIV setting to 4 µs/div or faster, the acquisition mode will change to Normal because the sample rate is fast enough that Peak Detect is unnecessary. The oscilloscope does not display a message to tell you that the mode has been changed to Normal.

Average:

Use this mode to reduce random or uncorrelated noise in the signal to be displayed. Acquire data in Normal mode and then average a great number of waveforms. Choose the number of acquisitions (4, 16, 64 or 128) to average for the waveform.

 Stopping the Acquisition:

When you are running the acquisition, the waveform display is live. Stop the acquisition (press the RUN/STOP button) to freeze the display. In either mode, the waveform display can be scaled or positioned by vertical and horizontal controls.

 Equivalent Acquisition:

Just repeat the Normal acquisition. Use this mode to take a specific observation on repeatedly displayed periodic signals. You can get a resolution of 40 ps, i.e. 25 GSa/s sample rate, which is much higher than that obtained in real-time acquisition.

 The acquisition principle is as follows.

 

 As shown above, acquire input signals (cycle repeatable) for more than once at a slow sample rate, arrange the sample points by the time they appear, then recover waveforms.

 UTILITY

Push the UTILITY button to display the Utility Menu as follows:

• System – Info Display the software and hardware versions
• Update Program – Insert a USB disk with upgrade program and the disk icon at the top left corner is highlighted. Press the Update Program button
• Save Waveform – Insert a USB disk and the disk icon at the top left corner is highlighted. Click on this icon and you can see the waveform pause for a while, being saved.
• Self-Calibration – Press this option and the Self Calibration dialog pops up. Press F6 to perform the self – calibration.
• Advance – Buzzer and time setups Press this button to see the dialog for buzzer and time setups.

 Self-Calibration:

The self-calibration routine can optimize the precision of the oscilloscope to fit the ambient temperature. To maximize the precision, you should perform the self- calibration once the ambient temperature changes by 41 °F (5 ℃) or more. Follow the instructions on the screen.

Tip: Press any menu button on the front panel to remove the status display and enter a corresponding menu.

CURSOR

Push the CURSOR button to display the Cursor Menu.

• Type: Off, Voltage, Time
• Source: CH1, CH2, MATH, REGA, REFB
• Select Cursor: S, E
• Delta: Display the difference (delta) between the cursors.

Moving Cursors:

 Press the key near Select Cursor to select a cursor and turn V0 to move it. Cursors can be moved only when the Cursor Menu is displayed.

DISPLAY

The waveform display is affected by settings of the oscilloscope. A waveform can be measured once it is captured. The different styles to display a waveform on the screen give significant information about it.

There are two modes to display waveforms Single-window and Dual-window.Push the DISPLAY button and the following menu appears.

• Type: Vectors, Dots
• Persist: OFF 0.2 S-8 S Selectable Infinate
• Format: YT, XY
• Contrast: 0-15 16 ranks adjustable, with progress bar to display
• Grid: Dotted Line, Real Line, OFF
• Grid Intensity: 0-15 16 ranks adjustable, with a progress bar to display.

  Fast Action Buttons

AUTOSET: Automatically set the oscilloscope controls to generate a usable display of the input signals. Refer to the following table for relative content.
SINGLE SEQ: Acquire a single waveform and then stop the acquisition.
RUN/STOP: Continuously acquire waveforms or stop the acquisition. HELP: Display the Help menu.
DEFAULT SETUP: Recall the factory setup. Refer to the following table for relative content. Save to USB Disk: Save all displays on the screen to a USB device, just like the screen capturing function of a computer.

AUTOSET

Autoset is one of the advantages digital oscilloscopes have. When you push the AUTOSET button, the oscilloscope will identify the type of waveform (sine or square wave) and adjust controls according to input signals so that it can accurately display the waveform of the input signal.The Auto-set function examines all channels for signals and displays corresponding waveforms. Auto-set determines the trigger source according to the following conditions.

• If multiply channels get signals, the oscilloscope will use the channel with the lowest frequency signal as the trigger source.
• If no signals are found, the oscilloscope will use the lowest-numbered channel displayed in Auto-set as the trigger source.
• If no signals are found and no channels are displayed, the oscilloscope will display and use Channel 1 as the trigger source.

Sine Wave: When you use the Auto-set function and the oscilloscope determines that the signal is similar to a sine wave, the oscilloscope displays the following options.

• Multi-cycle Square
• Single-cycle Square
• FFT
• Undo Setup

Square Wave or Pulse: When you use the Autoset function and the oscilloscope determines that the signal is similar to a square wave or pulse, the oscilloscope displays the following options

• Multi-cycle Square
• Single-cycle Square.
• Rising Edge
• Falling Edge
• Undo Setup

Help

Push the HELP button to display the Help menu which provides topics covering all the menu options and controls of the oscilloscope.

Default Setup

When you push the DEFAULT SETUP button, the oscilloscope will display the CH1 waveform and remove all the others. When you are at the default setup, press F1 to Undo Pre-set. Then the oscilloscope returns to the status before default setup. The table below gives the options, buttons and controls that change settings at default setup.

The following settings do not change when you push the DEFAULT SETUP button.

• Language Option
• Saved Settings
• Saved Reference Waveforms
• Display Contrast
• Calibration Data

 Multi-functional Knobs and Buttons

 V0: Multi-functional knob. Under different menu options, it supports selecting menu options (MEASURE), moving cursors and levels (Slope Trigger). Press this knob to reset data (trigger hold-off, overtime of the overtime trigger and slope trigger), select menu options and so on. Easy to operate.

F7: Push this button in single-window mode to switch between dotted line display and cross display. Push it in dual-window mode to perform auto-cruise.

F0: Hide/Show button. Push it to hide the menu options on the right side of the screen and give a full screen display of waveforms. Push it again to show the menu options.

F1-F5: These five buttons are all multi-functional. They are in charge of selecting corresponding menu options on the screen in different menu modes. For example, in the UTILITY menu, F1-F5 respectively correspond to ‘System Info’ – ‘Advance’.

F6: This functional button is mainly used to turn pages and confirm a selection, such as ‘next page’, ‘previous page’, and ‘press F6 to confirm’ appearing when you push Self Calibration option.

Signal Connectors

See the figure below to find the three signals connectors and a pair of metal electrodes at the bottom of the oscilloscope panel.

1. CH1, CH2: Input connectors for waveform display, through which to connect and input the signal to be measured.
2. EXT TRIG: Input connector for an external trigger source, though with to connect and input the external trigger signal.
3. Probe Compensation: Voltage probe compensation output and ground, used to electrically match the probe to the oscilloscope input circuit. The probe compensation ground and BNC shields connect to earth ground and are considered to be ground terminals. To avoid damages, do not connect a voltage source to any of these ground terminals.

 Logic Analyzer Channels Setup

The mixed signal oscilloscope equipped with 16 channels logical analyzer, which provides 16 logical channels, is able to carry out the measurement on mixed signals with the other 2 analog oscilloscope channels. You may open (or close) a single channel or a group of channels (8 channels), set the size of waveforms, change the display position of digital channels on the screen and select threshold type.

Press F7 button twice, the system will display the menu of logic analyzer channel. Please see the description in following table.

Function Menu	Settings	Description
D7-D0		Setup the channel group:
D7-D0 D15-D8		Setup the channel group: D15-D8
Current	<D15- D0>	Select the removable current digital channel
Threshold	TTL CMOS ECL User	Select the threshold types for all the digital channels. To setup the level value of threshold when select the User type.
User		Setup the threshold level value in user-defined type.

1． Display and Rearrange the Digital Channels

• Press F7-> F7->D7-D0 or D15-D8 to enter the channel group setup menu and open or close the display of the digital channels.
• (2) Press F7-> F7->Current to enable the multifunction knob to select digital channels. Turn the multi-function knob to select the digital channels and the number of the selected channel will be displayed in red.
• (3) Press multi-function knob, and turn it to make the selected channel reposition on the screen.

Menu display as follows.

2． Setup the Threshold Type of the Digital Channels Press F7-> F7->Threshold Type, select the pre-set threshold type or select the user-defined type to set your own threshold level. Menu display as follows.

• Threshold Description Threshold type: TTL CMOS ECL User-defined
• Threshold level changes between 2.6 V 2.5 V -1.3 V -8 V to +8 V.
• Setup the Channel Group
• Press F7-> F7->D7-D0 or D15-D8, the system will display D7-D0 or D15-D8 channel group setup menu, open or close a single channel or a group channel (with 8 channels for a group) and setup the size of the waveforms

 Open and close single digital channel

Press F7-> F7->D7-D0->channel setup, turn the multifunction knob to select the digital channel you want to open or close. Press the no. 1 menu operating key of channel setup or the multifunction knob to open or close the channel. When the channel is open, the box of the operating key of the channel setup menu is in green; When close, the box is in white.

 Compulsively open or close all of the digital channels

Press F7-> F7->D7-D0->D7-D0 to open all or close all, or push D15-D8->D15-D8->open all or close all to Compulsively open or close all the selected digital channels. Open or close a channel, turn the multifunction knob to select the channel, then press channel setup-F1 button or the multi-function knob.

Setup the size of digital channel waveforms

Press F7-> F7->D7-D0->waveform size, or push D15-D8->waveform size to select the size of the digital channel waveforms.

Reset the display of the digital channel waveforms

Press F7-> F7->D7-D0->reset, or push D15-D8->reset to make the digital channel display reset

Troubleshooting

Problem Settlement

If the oscilloscope does not start up at power on, follow these steps:

• Check the power cord to verify it has been connected properly;
• Check the power on/off button to ensure it has been pushed;
• Then restart the oscilloscope

If there is no display of waveforms on the screen when the oscilloscope is turned on, follow these steps:

• Check the probe to assure its proper connection to the input BNC;
• Check the channel switch (such as CH1, CH2 menu buttons) to make sure it has been turned on;
• Check the input signal to verify it has been connected to the probe correctly;
• Affirm that all measured circuits have signals to output;
• Turn up the magnitude for DC signals with large magnitude;
• In addition, you may press the Auto Measure button to perform an automatic detection of signals at first.

If the waveform of the input signal is distorted seriously, follow these steps:

• Check the probe to assure its proper connection to the channel BNC;
• Check the probe to assure its good connection to the measured object;
• Check the probe to verify it has been well calibrated. Otherwise, refer to the content about calibration described in this manual.

If the waveform is rolling continuously on the screen but cannot be triggered, follow these steps:

• Check the trigger source to make sure it consistent with the input channel;
• Check the trigger level to assure its correct adjustment. You may push the TRIGGER LEVEL knob or press the SET TO 50% button to reset the trigger level back to the center of the signal;
• Check the trigger mode to confirm it is a right choice for the input signal. The default trigger mode is edge trigger. However, it is not suitable for all kinds of input signals

Accessories

 Standard Accessories

Sketch	Description
	X1, X10 two passive probes. The passive have a 6 MHz bandwidth (rates 100 Vrms CAT III) when the switch is in the X1 position, and a maximum bandwidth (rates 300 Vrms CAT II) when the switch is in the X10 position. Each probe consists of all necessary fittings.
	A power cord special for this product. In addition to the power cord shipped with your instrument, you may purchase another one certified for the country of use.
	A USB A-B line, used to connect external devices with USB-B interface like a printer or to establish communications between PC and the oscilloscope.
	16 channel cable for logic analyser
	A software installation CD.

General Care and Cleaning

General Care

Do not put or leave the device in a place where the LCD display will be exposed to direct sunlight for long periods of time.
Note: To avoid damage to the oscilloscope or probes, do not expose them to sprays, liquids, or solvents.

Cleaning

Examine the oscilloscope and probes as often as operating conditions require. To clean the exterior surface, perform the following steps:

1. Use a lint-free cloth to remove floating dust on the outside of the oscilloscope and probes. Take care to avoid scratching the display filter.
2. Use a soft cloth dampened with water to clean the oscilloscope. For more efficient cleaning, you may use an aqueous solution of 75 % isopropyl alcohol.

Note: To avoid damage to the surface of the oscilloscope or probes, do not use any corrosive or chemical cleaning agents.