ADH 2/15/2014 Oscilloscope and Function Generator Operation Instructions
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Channel Selection
BNC Cable Ports
Figure 1. Oscilloscope front panel
1.)
After making sure that the power, mouse, and keyboard cables are plugged in, turn the
Oscilloscope on by pressing the “Power Switch” in the lower left corner of the
Oscilloscope’s front panel (Fig. 1). (The Oscilloscope will take a few minutes to boot up.)
2.)
After the Oscilloscope has booted up completely it should directly go to the measurement
screen. Using the mouse, click on the “mouse” icon in the top right corner of the screen
(this will enable you to use the mouse on the graphical interface).
3.)
Check to make sure the BNC cable from the Channel “1” port on the Oscilloscope (Figs. 1,
3) is connected to the port labeled “Sync Out 2Vpp” on the F31 Function Generator (Fig.
2) (This is the sync pulse which triggers the Oscilloscope to record data). Check to make
sure the BNC cable from the Channel “4” port on the Oscilloscope is connected to the port
labeled “Output 50 Ω” on the F31 Function Generator.
Frequency
FREQUENCY
WAVEFORM
2.0
1.0
3.0
0
PWR
ON
OFF
x 1M
x 100K
x 10K
x 1K
x 100
x 10
DC
OUTPUT LEVEL
OFFSET
+
Sync Out
2Vpp
‐
Output
50 Ω
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2
1
0
Figure 2. F31 Function Generator
Vertical scale AC/DC coupling
Vertical offset
Channel selection
Input resistance Figure 3. Vertical settings control and channel selection for Oscilloscope
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Horizontal offset
Horizontal scale
Figure 4. Horizontal settings control for Oscilloscope
Figure 5. Trigger settings control
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4.)
Make sure the “Output Level” knob on the Function Generator is set below 3 (Fig.
2). Turn the Function Generator on by pushing the top side of the “PWR” switch in.
5.)
Turn on the channel 1 input by pressing the “1” “Channel Selection” button once (Fig. 3).
It should light up green. This channel can also be turned off by pushing the same button
again.
6.)
Push the “Coupling” button until the “DC” LED lights up. Push the “Input” button until
the “50Ω” LED lights up (see figure 3). (Do this for both channel “1” and “4”).
7.)
In the trigger panel on the Oscilloscope (Fig. 5), push the “Mode” button until the “Edge”
LED is lit (this tells the Oscilloscope to begin acquiring data at the edge of the trigger
signal). Push the “Source” button until the “1” LED is lit (this tells the Oscilloscope to use
channel 1 as a trigger which is the sync pulse from the Function Generator). Push the
LED is lit (this tells the Oscilloscope to begin acquiring
“Slope” button until the
data when the trigger signal rises above the trigger level). Push the “Sweep” button until
“Trig’d” LED is lit, and push the “Coupling” button until the “DC” LED is lit.
8.)
Use the mouse to click on the “Setup” drop-down menu, click on “Acquisition”. A dialog
box should appear. Check the settings. In the “Sampling Mode” section choose “Real
Time”. In the “Memory Depth” section choose “Automatic”. In the “Sampling Rate”
section choose “Automatic. In the “Configuration” section choose 4 GSa/s (gigasamples/
second). In the “Averaging” section choose “Enabled” and change the “# of Averages” to
50 by clicking on the number and typing 50 (This means that the waveform on the screen
is actually an average of 50 laser shots). In the “Digital Filtering” section choose “Sin(x)/x
Interpolation”. Hit close to apply the settings.
9.)
On the Function Generator change the small knob (coarse adjustment) labeled
“Frequency” to the “x 1K” setting (Fig. 2). Turn the Large knob on the left of the
“Frequency” label to “1.0” (this is the fine adjustment of the frequency). Turn the “Output
Level” knob to “2”.
10.) Using the horizontal scale settings on the Oscilloscope (Fig. 4) turn the large “Horizontal
Scale” knob until the “Horizontal Scale” reading on the Oscilloscope is 500 μs/div (Fig.
6). Using the vertical scale settings (Fig. 3) turn the vertical scale knob for channel 1 until
the “Vertical Scale” reading on the Oscilloscope is 200 mV/div (Fig. 6). (At this point a
waveform resembling Fig. 6 should be on the Oscilloscope screen, with a frequency of 1
kHz).
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Vertical scale settings for each enabled channel (1‐4) Quick Measurements Horizontal scale setting (same for all channels)
Figure 6. Oscilloscope graphical interface screen showing Function Generator sync pulse output.
11.) If you do not see a waveform on the screen adjust the “Trigger Level” knob counter
clockwise until the waveform appears. (This sets the necessary voltage to trigger data
acquisition by the Oscilloscope).
12.) Press the channel “1” button once until the “1” button light is out. Press the channel “4”
button once to turn it on. Push the “Input” button until the “50Ω” LED lights up. Set the
vertical scale for channel “4” to 500 mV/div.
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13.) Select the different type of waveforms and observe their shapes on the Oscilloscope screen
using the “Waveform” selection knob on the Function Generator (Fig. 2). Choose the
selection knob = Square wave,
, = Triangle wave,
, = Sine wave,
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14.) Use the “Waveform” selection knob on the Function Generator to produce a Sine wave.
Use the coarse adjustment “Frequency” knob on the Function Generator to set the
frequency to “x 100K”. To view this wave properly you must change the horizontal scale
setting to ~5 μs/div (turning the horizontal scale clockwise will decrease the timescale).
(This should allow you to see a Sine wave with only a few wavelengths on the screen.)
15.) On the Oscilloscope click the “Measure” drop-down box at the top of the screen, click
“Markers”, and choose “Track Waveforms”. Change “Marker A” and “Marker B” to
“Channel 4”, hit close. Two pairs of markers should appear on the screen on the channel 4
waveform.
16.) The values of the X and Y coordinates are shown at the bottom of the screen (You may
have to click on the “Markers” tab in this area to view the markers readings). On the
“Markers” measurement screen there is a row marked “Δ” which gives the difference
between the “Marker A” and “Marker B” positions.
17.) Use the markers to measure the period of the wave (the period is the time it takes for the
wave to repeat its pattern). For the sine wave you can do this by clicking and dragging
“Marker A” until it intersects with a 0V ± 20 mV point on the wave (you must click on the
vertical line corresponding to “Marker A” and you can only drag markers horizontally).
You can use the “Y” measurement on the “Markers” measurement screen to get an exact
measurement of the Y-coordinate of the marker. Click and drag “Marker B” until it is one
wavelength away from “Marker A”. (There should be one minimum amplitude and one
maximum amplitude part of the wave between the two markers). Use the “Markers”
measurement screen to get close to this 0V point. Record the “Δ” value in the “X”
column. This is the period of the wave. Use this value to calculate the frequency of the
wave. Record these values in your lab notebook.
18.) Move Markers “A” and “B” to a minimum and maximum position on the wave,
respectively. Record the “Δ” value in the “Y” column. This is the peak-to-peak amplitude
of the wave (commonly the amplitude of a wave is reported as half this value and is called
the peak amplitude). Record these values in your lab notebook.
19.) On the left hand side of the Oscilloscope screen there are a number of buttons
corresponding to the Oscilloscope’s built in “Quick Measurements” (Fig. 6) functions. If
you hold the cursor over each button it will tell you which measurement it will perform.
Press the 4th button from the top which will measure the frequency of the wave in Hz. The
output of this measurement is shown in the bottom portion of the screen under the
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measurements tab. The button below that “V p-p” will give you the peak-to-peak
amplitude of the wave in volts. The bottom button “V avg” (choose “Channel 4” and the
“Single Cycle” measurement) will give you the average amplitude of the wave in volts.
Record these measurements in your Lab Notebook and comment on how they compare to
the Function Generator “Frequency” and “Output Level” settings as well as the
measurements you took using the markers.
20.) To save this waveform, first make sure the USB flash drive is plugged into the USB hub
cable (Do not plug flash drive directly into the oscilloscope). Save this waveform for
further analysis by clicking the “File” drop-down menu, click “Save”, click “Waveform”.
Under destination choose “drive e”. Under the “Source” choose “channel 4”. Under
“Type” choose “XY Pairs (.csv)”. Choose a file name that will be easily recognizable
since each file will only contain a list of X and Y values. To save the data HIT ENTER.
DO NOT HIT OK. Doing anything else frequently freezes Windows.
21.) On the Oscilloscope click the “Analyze” drop-down box and choose “Math/FFT…”.
Click “f1”, click the “Display On” button, choose “Invert” under the “Operator” dropdown menu, and choose “Channel 4”, then hit “Close” (this will display the inverted form
of the wave, i.e. finv(x) = - forig(x)).
22.) On the Oscilloscope click the “Analyze” drop-down box and choose “Math/FFT…”.
Click “f1”, and make sure the “Display On” button is checked. Choose “Differentiate”
under the “Operator” drop-down menu, and choose “Channel 4”, then hit “Close” (this
will display the derivative of the waveform, i.e. fdiff(x) = df(x)/dx).
23.) On the Oscilloscope click the “Measure” drop-down box at the top of the screen, click
“Markers”, and choose “Track Waveforms”. Change “Marker A” and “Marker B” to
“function 1”, hit close. You can now use the markers to make measurements on the
differentiated waveform. In your lab notebook comment on the shape of the differentiated
waveform and its relationship to the original waveform (e.g., where is the maximum and
minimum of the derivative with respect to the original waveform? What is the frequency
and amplitude of the derivative waveform?). Save the differentiated waveform the same
way you saved the actual waveform but make sure to change the source to “function 1.”
24.) Repeat steps 15-23 for a Square wave with a frequency of 500 Hz, and a Triangle wave of
2 MHz. You will have to adjust the horizontal scale settings to view these waves properly.
You should calculate the approximate scale setting by determining the period of each wave
and then setting the horizontal scale setting ~2-3 times that number so that you will be able
to view a few cycles of the wave. Make sure to save a copy of each waveform and the
differentiated waveform. Also, make comments on the differentiated waveform of both
new waveforms in your lab notebook.
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25.) When you are finished with these measurements, turn off the Function Generator, then
press the “Clear Display” button on the Oscilloscope located at the top row of buttons
(Fig.1, “Acquisition and General Controls) to clear the screen, lastly press and hold the
“Default Setup” button (in the same row of buttons as the “Clear Display” button) until the
Oscilloscope returns to its default settings.
26.) Leave the Oscilloscope on so that the TA can take the USB flash drive and transfer the
files to your USB flash drive.
27.) (For the TA), to eject the flash drive hit CTRL+ESC on the keyboard to access the
windows “Start Menu”, click on “Programs”, click on “Windows Explorer”, find the USB
flash drive (drive e), right click on it and choose “Eject” (There will not be any message
telling you that it is safe to remove). Then remove the flash drive from the USB hub cable.
Turn off the Oscilloscope by momentarily pushing the power button in the lower left
corner. Turn off the monitor. After transferring the files return the CHEM 343 flash drive
to the oscilloscope’s USB hub cable.
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