biomedical instrumentation lab

· Note 1 (Course Expectations): o The course expectations are in the syllabus. If you do not get one for some reasons, please check with your classmates to get a copy. Report templates will also be sent to students for preparing and writing the reports.

· Note 2 (Convention of Illustration Photos in Classnotes): Please notice that the convention in all classnotes of this course is that the displays on the instruments are the results after a button has been pushed or a selection has been made. Therefore, to find out what selection was made on a screen menu, a photo that precedes it should be checked. For example, if a menu item “Cardiac” is selected from a function generator, the screen of the function generator shows the result of the selection that may contain a new menu that may not have the option “Cardiac” anymore.

· Note 3 (Interferences from Your Electronics): Your electronics such as cell phone chargers may not be plugged into any of the lab power outlets to avoid interferences of your electronics with the circuits you are building or testing. This will not only affect you (you may take a lot of time just to find out that the reason why your circuits do not work is due to your electronic devices plugged into the power outlets) but also affect other students nearby.

· Note 4 (Margin of the Classnotes): The wide right margin (1.5 inches) of the classnotes is purposely left blank for students to add notes when the classnotes are printed out.

· Note 5 (Properly Naming Your Saved Files): For all the labs in this semester, you will find the item numbers such as “D1.001”, “D1.002”, and so on, where “D1” means that the items belong to the lab protocol of the Lab #1 classnote, and “.001” means the first item. The items will contribute to part of grade of your reports (please see the templates of the reports for details). Wherever applicable, please use the lower case of these item number as the names of the files to be saved. For example, use “d1.001.jpg” for a JPEG image file related to Item “D1.001”. This allows you to organize and find your results in the computer when you write your reports. It may also help TAs to check your results.

· Note 6 (Transfer Files to Your Personal Computer Accounts): You must transfer all of your saved files to your engineering account using WinSCP software and then delete the transferred files from the computer desktop. Two things to consider: (i) If your engineering account is out of space, you could email the files to your email accounts so that you do not have to look everywhere for files that you need or have the problems of your files being deleted or overwritten by others who use the same computers. In addition, periodical computer maintenances will wipe out everything by reformatting the hard disks. (ii) If the files are too big to email, as a last resort, you could save your files to other devices such as a USB thumb drive. (Notice that some USB drives will infect the computers with viruses and thus use them with care. In addition, frequent uses of USB drives may cause connection problems for the USB sockets of the computers due to wear and tear.)

· Caution on Using Oscilloscopes: o Please do not use the “Utility” button on the oscilloscope to adjust “I/O” setting from USB to GPIB. If you do so, your Intuilink software will no longer able to capture waveforms from the oscilloscope. o Please do not change the trigger “Mode/Coupling” to anything other than “Auto”. If you make such change, you would not be able to see scan lines on the oscilloscope when you push the button “Auto” on the oscilloscope and you may experience error message of “No Data”. o In short, there are numerous adjustments on oscilloscopes and thus if you try to make adjustments without knowing what you are doing, you may not be able to recover the oscilloscopes to their original settings and thus may affect experiments of yours and others. Please check on the web for the manuals of the oscilloscopes that you are using to know the meaning of the adjustments before you try to do “creative” adjustments!

· The goal of this lab is for students to be familiar with major instruments, devices, and software in the Lab.

· Save your computer captured oscilloscope files as .png files with IntuiLink.

· Transfer all of your saved files to your engineering account using WinSCP software and then delete the transferred files from the lab computer.

· TA(s) (Task #1): Do Lab First: TAs should complete the same lab before students start their labs so that TAs can anticipate the questions from the students and can help students better.

· TA(s) (Task #2): Guidance at Beginning of Lab: TAs should give a brief guide to students at the beginning of each lab to address lab specific issues such as identifying cables and their leads, and others.

· TA(s) (Task #3): Clean Up Files: TAs should make sure students have copied their saved files and then deleted the copied files from the computers before they leave the lab. Any files saved by students but have not been deleted after students leave should be deleted by TAs if students could not delete them for some reason. This is important to avoid confusing different groups of students and clustering the computers.

· TA(s) (Task #4): Check Student Files: TAs should check all the plots and figures saved to files by students. If there are some problems with the files, students may need to make corrections.

· There are three types of oscilloscopes in the lab. The type of oscilloscope for Station #1 to #6 is shown below (Agilent DSO6012A (60MHz)):

· The type of oscilloscope for Station #7 to #8 is shown below (Agilent DSO1002A (60MHz)):

· The type of oscilloscope for Station #9 is shown below (Agilent DSO54621A (60MHz)):

· There are two types of function generators in the lab. The function generators for Station #1 to #7 are shown below (Agilent 33220A (20MHz)):

· The function generators for Station #8 to #9 are shown below (Agilent 33210A (10MHz)):

• The power supplies for all stations are shown below (Agilent E3631A) – check to make sure the two black posts and one green post are connected together as a ground post (see green wire below for ground):

• There are two types of desk-top multimeters in the lab. The multimeters for Station #1 to #8 are shown below (Agilent 33401A) (the multimeter for Station #9 is Agilent 33405A and is not shown):

• The device you will use to digitize the signal from the circuits you will make is from a company called National Instruments (NI) as shown below (NI USB-6009):

• There are two types of HP GPIB to USB converters (Agilent 82357A for Stations #1 to #8 on the left and National Instruments GPIB-USB-HS for Station #9 on the right) for oscilloscopes:

• The box with organized jump wires is for you to construct electrical circuits:

• The screw driver tool is used for you to remove integrated circuit chip (such as the operational amplifier OP37G) and other devices and jump wires from prototyping breadboard:

· The prototyping breadboard is for you to build circuits.

· Notice that this particular board contains three vertical banks. Each bank is divided into the left and right sections. There is no electrical connection between the sections. There are multiple rows of a set of five holes in each section. The five holes in each row are electrically connected, but there are no electrical connections between rows. A horizontal strip on the top of the board contains two rows of holes. Each row is electrically connected but there is no electrical connection between the two rows. You may also notice that there are four strips in the vertical direction placed evenly from left to right and they are interleaved with the banks. The vertical strips are a rotation of 90 degrees from the horizontal strip described above.

· There are also breadboards of four vertical banks in the lab. But those are for making bigger circuits that need a larger board area. (The smaller boards will provide adequate spaces for our labs.)

· As a convention, the Green post is connected to ground. The red post is connected to +15V of the power supply and the yellow post is connected to the -15V in our experiments.

· Breadboard with three vertical banks of prototyping areas:

· Breadboard that shows all hidden electrical connections underneath the holes (blue lines):

· Breadboard with four vertical banks of prototyping areas:

• An example of operational amplifier or Op Amps (OP37G from Analog Devices). Pin #1 (indicated by the red circle) is the lower-left most position (when the semicircle groove is on your left side and you are looking from the top side of the device as shown):

• An example of potentiometer (shown on the picture is one that can vary from 0 to 10K Ohms) is shown below. The resistances between the center pin relative to the 1st (has a larger distance between the pins) and 2nd (has a smaller distance between the pins) outer pins are variable while the resistance between the two outer pins is fixed to 10K Ohms in this example. (“103” means 10 with 3 zeros followed, i.e., 10,000 Ohms that means

10K Ohms. In our labs, we will use 20K Ohm potentiometers.)

· An example of resistor (10 K Ohms) (brown, black, orange color bands):

· Resistor color codes for values of resistance:

· The resistor color codes that are used to determine the resistance of resistors:

• Examples of capacitors (1 micro Farad or 1 mF metallized polyester capacitors):

· The shelves on the back of the room are for you to put your breadboards and hanging cables:

· There are four types of cables. From left to right:

· (1) BNC-to-BNC,

· (2) BNC-to-alligator clips,

· (3) alligator-clip-to-alligator-clip, and

· (4) banana-plug-to-banana-plug:

· The rack drawers are for organizing your components:

· A closer view of the rack drawers:

· Turn on the monitor by pushing its power button once if it is not already on. Turn on the computer by pushing the button once near the USB sockets (lower part of the computer) if the computer is not already on:

· After login to the “Bioinstrumentation” account (the password will be given during the class), you will get a screen similar to the following (due to upgrades to computers, the screen layout may be a little different):

· There are several programs that you need to use for the lab. These programs can be started from the desktop or the Microsoft Shortcut bar on the upper right side of the screen.

These programs will be shown one-by-one as follows. The names of the programs are below the icons on the desktop. They can also be seen by placing the mouse over the icons of the Microsoft Shortcut bar on the upper-right corner of the screen for a couple of seconds.

· The following program is called “IntuiLink” that is used to transfer and save the waveforms that you see on the screen of the oscilloscopes (double click the icon to start the program and then click the “Get Data” icon in the program):

· An example of waveform (a test signal on oscilloscope) captured by the oscilloscope with IntuiLink (the use of the oscilloscope will be introduced in next sections). The front panel is an exact copy of the oscilloscope screen and the one behind it gives users some parameters of the waveform, such as the starting time and voltage and the ending time and voltage of the waveform). When saving the oscilloscope screen to a file, the top panel should be saved since it contains all the setting parameters of the oscilloscope. Click on File->Save As … >Desktop->Save as type “PNG” to save to computer desk top as a .png file.

· More example of the waveform (the oscilloscope test signal) captured with IntuiLink:

· The “Measurement and Automation” program is used to control the NI USB-6009 signal digitizing device to digitize signals from your circuits to be built later:

· Noise signal captured by the NI USB-6009 device when the inputs of the device are not connected to any signal sources (double click on “Devices and Interfaces” on the left panel, select the device NI USB-6009, open “Test Panels”, select “AI1” or “Dev1/ai1” from the Channel Name if it has not been selected yet, ensure Mode is “On Demand”, select “RSE” from the Input Configuration, and then click the green “Start” button for the test). Please (i) complete the test on the Test Panels and then (ii) close the Test panels and click “Self-Test” to complete a self-test.

• The “MultiSim” program from the National Instruments (NI) for circuit schematics and simulations is shown as follows by double-clicking on the icon on the computer desktop:

· The “LabView” program from the National Instruments is to make virtual instruments such as filters:

· Note: The LabView software is updated periodically. (1) Therefore, please start the LabView from the desktop or the Microsoft Short Cut Bar on the upper-right corner of your computer (do not start it from the Windows “Start” menu on the lower left corner). (2) Also, the screen shots of LabView programming steps are for illustration purpose only and they may be slightly different from what you see in the latest version.

• The Microsoft Photo Editor program is used to handle and manipulate screen captured images:

· The “winSCP” program allows you to copy files obtained from the lab experiments (saved on the desktop) to your Engineering Accounts in the College of Engineering at The University of Toledo for lab reports. Students are not allowed to leave files on the computers in the lab (the local machines) after each lab. Files on the lab computers may be deleted periodically through reformatting of the hard disk for maintenances. Or, other students may overwrite or delete your files since the lab computers are shared by different students.

· Open the winSCP program:

· Login screen:

· Enter your Engineering User Name:

· Enter Your Engineering Password:

· winSCP panel (files on the left are in this computer and files on the right are at your engineering account – drag files on the left (or from the desktop) to right panel will copy files):

· Change folder to desktop:

· Locate file “waveform1.jpg” or “waveform1.png” (or any filename that you have made) and then drag to copy the file:

· Confirm your copying action:

· Your copied file is now in your engineering account for use in your reports:

· Delete the file(s) from the desktop ot other locations:

• The irlab software (program) is used for image reconstruction in Labs #6 to #9. It will be introduced in detail later in Lab #6. The program can be started either from the desktop or the Microsoft Shortcut bar on the upper right of the screen.

• The Microsoft Word program for viewing and writing documents or reports:

• The Microsoft Excel program for spreadsheets:

· Agilent DSO6012A oscilloscope is used in Stations #1 to #6. Please follow the procedures of oscilloscope in your station.

· Note: Except in this section (“Use of Oscilloscope”), all illustrations in other sections are based on Agilent DSO6012A and thus appropriate modifications to the operations of oscilloscopes should be made if you are not using Agilent DSO6012A.

· Note: If you find that the voltages measured with the oscilloscope is not what you expected, for example, it is 2 times bigger, 5 times bigger, or 10 times bigger, you should check to see if the input settings of the channel you used for the measurement are set incorrectly. The problem can be solved by pushing the enabling button of the channel of concern and then go to the “Probe” option displayed on the menu of the oscilloscope screen. Adjust the input of the channel back to 1:1 ratio (this means that the input voltage displayed will not be multiplied by a number other than 1). Each type of the oscilloscopes may have a slightly difference menu but all oscilloscopes are similar. For safe, you should check at the beginning of each lab to ensure that the ratio of all the channels is set to 1:1 to avoid problems in case senior design students use the oscilloscope while the labs are not in session.

· Connect the oscilloscope input CH1 (Channel #1) to the test wave source produced by the oscilloscope with a BNC-toalligator-clips cable. (The BNC male and female connectors are connected by pushing the male connector into the female and then turning the male clockwise to lock it. To disconnect, do the opposite, i.e., turning the male connector counterclockwise while pushing it in to unlock it first, then, pulling the male connector out. The male BNC connector is on the cable and the female BNC connector is on the oscilloscope.)

· Make sure to connect the black alligator clip to the ground pin and the red alligator clip to the signal pin as shown to avoid shorting the output of the signal:

· Turn on the oscilloscope:

• Push the “Auto Scale” button to set appropriate amplitude and time scale ranges automatically:

· Adjust amplitude scale per division of the displayed waveform:

· Adjust the time scale per division to increase or decrease the number of cycles of the waveform displayed:

· Do a Quick Measurement:

· Press the button as shown to bring up the manual:

· Choose “Measure Frequency” from the menu by rotating the “rotation” knob or by pushing the same button a number of times as needed:

· Push the “Cursor” button:

· Select left cursor by pushing the button as shown:

· Adjust left cursor:

· Select right cursor by pushing the button as shown:

· Adjust right cursor to measure the period:

• D1.001. Record the period and then calculate the frequency of the waveform from the period for your report.

· Measure amplitude of the waveform by pushing the button as shown:

· Select the first cursor as shown:

· Adjust the first cursor:

· Select the second cursor as shown:

· Adjust the second cursor to record the peak-to-peak amplitude:

• D1.002. Record the peak-to-peak amplitude of the waveform for your report.

• D1.003. Capture the waveform on the screen and save it into a file with IntuiLink for your report. (The procedure to capture the waveforms displayed on the screen of the oscilloscope is given in Section 1.3.4.2 “IntuiLink”.)

· Select “Roll” mode in the following steps so that low frequency signals such as the electrocardiogram (ECG) can be displayed naturally:

· In the “Roll” mode (waveform is moving to the left):

· Agilent DSO1002A oscilloscope is used in Stations #7 to #8. Please follow the procedures of oscilloscope in your station.

· One noticeable difference is that when data on the screens of these oscilloscopes are captured with “IntuiLink” Software described in Section 1.4.2, the front panel keys of these oscilloscopes are locked up. To release the keys, one has to push the button “Force” on the right-hand-side of the front panel and then push the “Run/Stop” button.

· Note: Except in this section (“Use of Oscilloscope”), all illustrations in other sections are based on Agilent DSO6012A and thus appropriate modifications to the operations of oscilloscopes should be made if you are not using Agilent DSO6012A.

· Note: If you find that the voltages measured with the oscilloscope is not what you expected, for example, it is 2 times bigger, 5 times bigger, or 10 times bigger, you should check to see if the input settings of the channel you used for the measurement are set incorrectly. The problem can be solved by pushing the enabling button of the channel of concern and then go to the “Probe” option displayed on the menu of the oscilloscope screen. Adjust the input of the channel back to 1:1 ratio (this means that the input voltage displayed will not be multiplied by a number other than 1). Each type of the oscilloscopes may have a slightly difference menu but all oscilloscopes are similar. For safe, you should check at the beginning of each lab to ensure that the ratio of all the channels is set to 1:1 to avoid problems in case senior design students use the oscilloscope while the labs are not in session.

· Connect the oscilloscope input CH1 (Channel #1) to the test wave source produced by the oscilloscope with a BNC-toalligator-clips cable. (The BNC male and female connectors are connected by pushing the male connector into the female and then turning the male clockwise to lock it. To disconnect, do the opposite, i.e., turning the male connector counterclockwise while pushing it in to unlock it first, then, pulling the male connector out. The male BNC connector is on the cable and the female BNC connector is on the oscilloscope.)

· Make sure to connect the black alligator clip to the ground pin and the red alligator clip to the signal pin as shown to avoid shorting the output of the signal:

· Turn on the oscilloscope:

• Push the “Auto Scale” button to set appropriate amplitude and time scale ranges automatically:

· Turn off the on-screen menu:

· Adjust amplitude scale per division of the displayed waveform:

· Adjust the time scale per division to increase or decrease the number of cycles of the waveform displayed:

· Select Measurement:

· Select “Time” submenu:

· Select “Period” by turning the knob:

· Press the knob to confirm the selection:

· Select “Frequency” by turning the knob and then press the knob to confirm the selection. The period and frequency will be displayed.

· Push the “Cursor” button:

· Select “OFF” from submenu:

· Select “Manual” from the submenu:

· Push the knob to confirm the selection:

· Select left cursor:

· Adjust left cursor:

· Turn off the left cursor adjustment:

· Select right cursor:

· Adjust right cursor to measure the period:

• D1.001. Record the period and then calculate the frequency of the waveform from the period for your report.

· Push the “Cursor” button a number of times until “Auto” is displayed:

· Press the “Measurement” again and then select “Voltage” submenu:

· Turn the knob to select the “Vpp” peak-to-peak value:

· Press the knob to confirm the selection:

· Turn the menu off:

· The peak-to-peak amplitude, Vpp, will be displayed.

· Push the “Cursor” button a number of times until “OFF” is displayed:

· Select “OFF” from submenu:

· Select “Manual” from the submenu:

· Push the knob to confirm the selection:

· Press the button below as shown until “Amplitude” is displayed:

· Select the first cursor:

· Adjust the first cursor:

· Turn off the first cursor adjustment:

· Select the second cursor:

· Adjust the second cursor to record the peak-to-peak amplitude:

• D1.002. Record the peak-to-peak amplitude of the waveform for your report.

· D1.003. Capture the waveform on the screen and save it into a file with IntuiLink for your report. (The procedure to capture the waveforms displayed on the screen of the oscilloscope is given in Section 1.3.4.2 “IntuiLink”.)

· After using IntuiLink via a computer, DSO1002A oscilloscope may not return to equipment operating mode and thus may not respond to any key input. To release the keys, one has to push the button “Force” on the right-hand-side of the front panel and then push the “Run/Stop” button.

· Select “Roll” mode in the following steps so that low frequency signals such as the electrocardiogram (ECG) can be displayed naturally:

· Turn the knob to “Roll” in the submenu:

· Push the knob to confirm the selection:

· In the “Roll” mode (the waveform below was not displayed since the sampling rate is only 1KHz that is the same as the signal frequency for this particular oscilloscrope, i.e., the sampling rate is too low for the signal):

· Turn the menu off:

· Agilent 54621A oscilloscope is used in Station #9. Please follow the procedures of oscilloscope in your station.

· Note: Except in this section (“Use of Oscilloscope”), all illustrations in other sections are based on Agilent DSO6012A and thus appropriate modifications to the operations of oscilloscopes should be made if you are not using Agilent DSO6012A.

· Note: If you find that the voltages measured with the oscilloscope is not what you expected, for example, it is 2 times bigger, 5 times bigger, or 10 times bigger, you should check to see if the input settings of the channel you used for the measurement are set incorrectly. The problem can be solved by pushing the enabling button of the channel of concern and then go to the “Probe” option displayed on the menu of the oscilloscope screen. Adjust the input of the channel back to 1:1 ratio (this means that the input voltage displayed will not be multiplied by a number other than 1). Each type of the oscilloscopes may have a slightly difference menu but all oscilloscopes are similar. For safe, you should check at the beginning of each lab to ensure that the ratio of all the channels is set to 1:1 to avoid problems in case senior design students use the oscilloscope while the labs are not in session.

• A larger view of the 54621A digital oscilloscope:

· Connect the oscilloscope input CH1 (Channel #1) to the test wave source produced by the oscilloscope with a BNC-toalligator-clips cable. (The BNC male and female connectors are connected by pushing the male connector into the female and then turning the male clockwise to lock it. To disconnect, do the opposite, i.e., turning the male connector counterclockwise while pushing it in to unlock it first, then, pulling the male connector out. The male BNC connector is on the cable and the female BNC connector is on the oscilloscope.)

· Make sure to connect the black alligator clip to the ground pin and the red alligator clip to the signal pin as shown to avoid shorting the output of the signal:

· Turn on the oscilloscope:

• Push the “Auto Scale” button to set appropriate amplitude and time scale ranges automatically:

· Adjust amplitude scale per division of the displayed waveform:

· Adjust the time scale per division to increase or decrease the number of cycles of the waveform displayed:

· Do a Quick Measurement:

· Press the button as shown to bring up the manual:

· Choose “Measure Frequency” from the menu by rotating the “rotation” knob or by pushing the same button a number of times as needed:

· Push the “Cursor” button:

· Select left cursor by pushing the button as shown:

· Adjust left cursor:

· Select right cursor by pushing the button as shown:

· Adjust right cursor to measure the period:

• D1.001. Record the period and then calculate the frequency of the waveform from the period for your report.

· Push the “Quick Measurement” button again:

· Measure amplitude of the waveform by pushing the button as shown:

· Select “Measure Peak-to-Peak” from the menu:

· Push the “Cursor” button again:

· Select “Y” from the menu:

· Select the first cursor:

· Adjust the first cursor:

· Select the second cursor:

· Adjust the second cursor to record the peak-to-peak amplitude:

• D1.002. Record the peak-to-peak amplitude of the waveform for your report.

• D1.003. Capture the waveform on the screen and save it into a file with IntuiLink for your report. (The procedure to capture the waveforms displayed on the screen of the oscilloscope is given in Section 1.3.4.2 “IntuiLink”.)

• Select “Roll” mode in the following steps so that low frequency signals such as the electrocardiogram (ECG) can be displayed naturally:

· Note: The Microsoft Photo Editor program is used to capture images on computer screen.

· Important: Please notice that in our labs, the direct current (DC) offset of the function generator must be set to zero if this has not already been done. If this is neglected and your function generator has a DC offset that is not zero, the measurements and results of this and future labs will not be correct and it may take a lot of time to troubleshoot to find out this problem. (Notice that when you turn on the function generator, the option “Offset” will be shown on the display.) For safe, you should check at the beginning of each lab to ensure that the offset is set to 0 to avoid problems in case senior design students use the equipment while the labs are not in session.

· Connect the function generator to oscilloscope with a 50 Ohm BNC-to-BNC cable (the one provided in the lab is a 50 Ohm cable):

· Make the connection:

• Turn on the function generator and the output waveform depends on the selection of the previous user:

· Push the “Utility” button:

· Select the “Output Setup” from the menu:

· Select the “High Z” mode to let the output to have a higher impedance since our load has a high impedance (this will ensure a correct reading of the amplitude of the signal):

· Click “Done” from the menu to end the selection:

• Select the square wave mode and Set “Offset” to “0VDC” if it is not set already.

· Change the frequency of the wave:

· Make a change to the frequency (change to 100 Hz):

· Select “Hz” unit for the frequency of the square wave:

· Select “Amplitude” from the menu:

· Change the amplitude of the square wave to 1:

· Select the unit of the voltage to Vpp:

· Enable the output of the function generator if it is not already enabled:

· Push “Auto Scale” on the oscilloscope to let it to determine an appropriate amplitude and time scales for the square wave signal from the function generator:

· Push the “Quick Measure” button:

· The frequency and amplitude values are shown on the lower part of the screen as indicated by the fingers below:

• D1.004. Compare the frequency and peak-to-peak amplitude of the waveform between what you set on the function generator and what you measured with the oscilloscope for your report.

· Produce a sine wave having 1 KHz frequency and 2 Vpp voltage (the subscript “pp” means peak-to-peak amplitude of the wave) instead of a square wave with the function generator, and then display it with the oscilloscope. Check the frequency and amplitude on the oscilloscope.

· D1.005. Compare the frequency and peak-to-peak amplitude of the waveform between what you set on the function generator and what you measured with the oscilloscope for your report.

· Produce the simulated (Pseudo) ECG signal built-in in the function generator by pressing “Arb” button:

· Select the “Select Waveform” from the menu:

· Select “Built-In” from the menu:

· Select “Cardiac”:

· Select “Frequency” from the menu:

· Type in the frequency (1 Hz):

· Select the unit “Hz” from the menu:

· Select “Amplitude” from the menu:

· Set the amplitude (1Vpp):

· Select the unit “Vpp” of the voltage from the menu:

· Push the “Main/Delayed” or “Menu/Zoom” button on the oscilloscope:

· Select the “Roll” mode from the menu:

• D1.006. (i) Capture the waveform on the screen and save it into a file with IntuiLink for your report. (ii) Compare the frequency and amplitude set on function generator with those measured.

· Produce a pseudo-ECG signal with 2 Hz frequency and 60 mVpp voltage, and then use the oscilloscope to display it using the “Roll” mode of the oscilloscope.

· D1.007. (i) Compare the frequency and peak-to-peak amplitude of the waveform between what you set on the function generator and what you measured with the oscilloscope for your report. (ii) If you see a higher noise as compared to 1Hz and 1Vpp pseudo ECG signal, please explain why.

• Turn off the oscilloscope:

• Note: After the “Output On/Off” button is pushed to turn on the output, the voltages and current limits cannot be adjusted.

• Turn on the power of the power supply (this power supply has three sets of outputs: (1) 6V, (2) 0 to 25V, and (3) 0 to -25V):

• Select +25V adjustable power:

· Push “Display Limit” to display the voltage and current limit of this the +25V adjustable power output:

· Adjust the voltage to +15V:

BIOE 4140 Biomedical Instrumentation Jian-yu Lu, Professor, Instructor

BIOE 4140 Biomedical Instrumentation Jian-yu Lu, Professor, Instructor

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· Toggle the “Voltage/Current” button to adjust the current limit:

Push the arrow:

· Continue to push the arrow:

Adjust the current to 0.035A or 35 mA that is to be used in all of our lab experiments to reduce the chance of burning out devices in the circuits and/or burning out the breadboards:

· Select the -25V adjustable power:

Adjust the voltage to -15V:

· Select current limit for adjustment:

Push the arrow:

BIOE 4140 Biomedical Instrumentation Jian-yu Lu, Professor, Instructor

BIOE 4140 Biomedical Instrumentation Jian-yu Lu, Professor, Instructor

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· Continue to push the arrow:

· Adjust the current limit to 0.035A or 35mA that is to be used in all of our lab experiments to reduce the chance of burning out devices in the circuits and/or burning out the breadboards:

· Connect a BNC-to-alligator-clips cable to the multimeter (make sure that the BNC connector on the banana-to-BNC adaptor plug is to the right hand side as shown below so that the polarity of the voltage measured is correct):

· Turn on the multimeter:

· Set the multimeter to measure direct current (DC) voltage:

· Connect the alligator clips to the power supply 25V adjustable power to measure voltages (black color to black and red to red):

· Set the output of the power supply to 15V if it is not already set:

· Enable the output of the power supply:

· Measuring the output voltage of the power supply:

· Disable the output of the power supply. You notice that the voltage displayed on the multimeter is changed:

· D1.008. Compare the voltage set on the power supply with that measured with the multimeter for your report.

· Produce +12 and -12V voltages with the power supply and then use the multimeter to measure the voltages of both the positive and negative outputs. Ensure that the current limit for both +12 and -12V are set to 0.035A.

· D1.009. Compare the voltages set on the power supply with those measured with the multimeter for your report.

· When measuring a current that flows through a resistor, the multimeter must be in series with the power supply that is also in series with the resistor to avoid damaging the multimeter and to be able to carry out the measurement.

· Disable the output of the power supply if it is not already disabled.

· Disconnect the alligator clips from the output of the power supply:

· Connecting yellow and black alligator-to-alligator cables to the output of the power supply (connecting yellow to red and black to black to the power supply as shown):

· Get a 10K Ohm resistor in series with the output of the power supply:

· Complete the circuit with the multimeter and the output of the power supply:

· Summary: The circuit connections are shown below (the yellow alligator-to-alligator cable is connected to the red post of the power supply at one end and is connected to the resistor at the other end, the black alligator-to-alligator cable is connected to the black alligator clip of the BNC-to-alligator-clips cable at one end and is connected to the black ground post of the power supply at the other end, and the red alligator clip of the BNCto-alligator-clips cable is connected to the other end of the resistor):

· Remove the banana-to-BNC adaptor plug and then plug it into the position for measuring currents (please rotate the banana-toBNC adaptor plug by 180 degrees and then insert it into the lower two holes to ensure that the ground remains the same):

· Connecting black to black and red to red for the banana-toBNC adaptor. I.e., the BNC connector on the banana-to-BNC adaptor plug should now be on the left hand side to ensure a correct polarity of the measurements, see the figure below:

· Press the “Shift” button for current measurement on the multimeter:

· Select the DC current measurement:

· Set the voltage of the power supply to +15V. Enable the output of the power supply and the current value is shown on the display panel of the multimeter (check to make sure that the circuit connections are correct before you enable the power supply and also ensure that the current limit of the power supply is set to 0.035A or 35mA to minimize the chance of damaging devices and equipments):

• D1.010. (i) Draw a circuit diagram of the circuit above using the electronic symbols given in Wikipedia

(https://en.wikipedia.org/wiki/Electronic_symbol ) and a small square with “+” and “-” leads to represent the multimeter. (ii) Measure the DC current with the multimeter. (iii) Calculate the current determined by the Ohm’s Law (V=+15V and R=10 KOhm). (iv) Compare what you measured with what you calculated and do analysis for your report.

• Disable the output of the function generator if it is not already disabled. Produce a sine wave having 60 Hz frequency and 1 Vpp voltage, and set the output of the function generator to “High Z”.

· Make sure that the position of the plug to the multimeter is set back to the position for measuring voltage (upper position), otherwise damage to the multimeter may occur. Press “AC V” button to measure alternating current (AC) voltage:

· Connect the BNC-to-BNC cable from multimeter to the function generator:

· Enable the output of the function generator (notice that the multimeter will measure the root-mean-square (RMS) value of the AC voltage, which is different from the peak-to-peak value of the voltage measured on an oscilloscope - please visit website at

http://www.learningaboutelectronics.com/Articles/What-ispeak-to-peak-voltage.php for an explanation of RMS value of an AC voltage):

• D1.011. (i) Measure the AC voltage with the multimeter. (ii) Calculate the RMS voltage with the formula for sine wave in Wikipedia above (V=1Vpp sine wave). (iii) Compare what you measured with what you calculated and do analysis for your report.

· Turn off the power supply:

· Remove the cables from the power supply and the multimeter:

· Turn off the function generator:

· Remove the cable from the function generator:

· Attach the BNC-to-Alligator-clips cable to the multimeter:

· Set the multimeter for resistance measurement:

· Measure the resistance of a 10K Ohm resistor (brown, black, orange color bands – see Section 1.3.3):

· Replace the 10K Ohm resistor with a 220 Ohm resistor (red, red, brown bands – see Section 1.3.3) and then do the measurement again.

· D1.012. (i) Record what you have measured for both the 10K Ohm and 220 Ohm resistors, and (ii) do analyses on any discrepancies of what you have measured and what you expect for your report. (iii) Are the errors within the tolerance of the type of resistors (carbon film resistors – see Section 1.3.3).

· Get a 20K Ohm potentiometer. With the help of the multimeter, set the resistances between the center pin and the 1st outer pin (has a larger distance between the pins) to (i) 0k Ohms, (ii) 5k Ohms, (iii) 10k Ohms, (iv) 15k Ohms, and (v) 20k Ohms, respectively, by rotating the screw of the potentiometer (clockwise to increase the value while counterclockwise to decrease the value). For each resistance value measured above, measure the corresponding resistance between the center pin and the 2nd outer pin (has a smaller distance between the pins). (See Section 1.3.3 for details of potentiometers.) Create Table D1.013 below.

· D1.013. (i) Record the results in Table D1.013 below (also calculate the column sum of each column), and (ii) do analyses on what you find for your report.

Table D1.013. Measurement Results.

• Turn off the multimeter. Disconnect the BNC-to-Alligator-clips cable from the banana-to-BNC adaptor plug by turning counterclockwise the BNC connector while pushing it in to unlock first, and then pull out the cable to remove it.

• D1.014. The electrical connections of the breadboard is shown in Section 1.3.3. Please use the knowledge to indicate all of the points (labeled by “A”, “B”, “C”, and so on) that are connected electronically for your report.

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

• Use the “winSCP” program to: (i) save your files to your engineering account and then (ii) delete the saved files from your desktop. Deleting from your computer desktop the files that you produced and transferred to your account would avoid confusing the groups that do the same lab using the same computer after you and also would prevent your results be misused by others. (Please follow Section 1.3.4 “Software to Use” above for steps to use winSCP if you forget how to do this.)

• After completing the lab, turn off (i) power supply, (ii) function generator, (iii) multimeter, (iv) oscilloscope, (v) computer, and (vi) monitor if they have not been turned off already. Disconnect the cables that you have used and put them on the hangers at the back of the room.

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