SKILLS TO BE LEARNED AND DEMONSTRATED IN THIS LAB
For design problems, clarify the purpose and required performance before start, then find circuit and values, build, test, and fine-tune for best results
Given black-box electronic system and what is expected from it, determine possible measurements and come to the conclusion about what might be wrong with it
READ PRIOR TO THIS CLASS:
Textbook’s Chapters 12, 13 (Schmidt, B. 2014. An Engineer's Guide to Solving Problems)
WORK
1. Download this file and save it as “ETEC104 Lab7 YourFirst LastName” to your H drive ETEC104 folder. Be responsible for saving you work at all times.
2. Complete the following tables in teams as indicated. Follow professor’s instructions for groups, equipment, and timing.
TEXTBOOK READ: Chapters 12, 13
Recommended to be done individually - prior to the class!
QUESTION
YOUR ANSWER
Ch 12: If I Could See it, I Could Fix it
a) You see pin 8 on 74LS00 (Quad 2-input NAND gate) bent and not reaching breadboard metal socket. How would this be manifested in IC’s performance?
b) You hear hum from your desktop computer. What are the possible sources of it?
c) You smell burning rubber from the wall AC outlet you use for your computer, desk lamp and extra heater. What is happening?
d) When touching your cellphone, you feel it warmer than usual. What could be a problem?
e) If you taste both electrodes of a battery with your tongue, you feel tingling sensation: is the battery good or bad? (it’s an outdated foolish way to test batteries so don’t do it, just answer what you think would happen)
a) It going to give out wrong input signal or no signal at all.
b) It could be overheating of the entire system, over speeding of the cooling fan, or faulty disk drive, faulty optical drives or damage processor. c) It means that a short-circuit has occurred and has caused overheating of the PVC material
d) Then the phone is running on the too much applications and has caused the battery to overheat.
It’s till good.
Ch 13: Measurements
a) What instrument is used as #1 in the electrical product development and troubleshooting? Which one as #2?
b) Does your measurement affect the thing being measured?
c) Based on your experience with ETEC101/102/104/116 labs:
i. Write an example of problems you are able to see with your own eyes. ii. Write an example of problems a voltmeter helps you to “see”? iii. Write an example of problems an ohmmeter helps you to “see”? iv. Write an example of problems a digital probe helps you to “see”?
v. Write an example of problems an oscilloscope helps you to “see”?
d) You record your1.2345V measurement as 1.2V. What % error did you just add to the measurement?
A)
I. Multimeter and
II. Oscilliscope
B) No it doesn’t
C)
I. Melting of bread board
II. Calculation of voltages across a resistor
III. Obtaining total value of resistance in a circuit
IV. Correct measurements of properties of electricity
V. Helped in viewing waveforms of a DC source and also an AC source
D) 2.875% error
Internet Research: Black Box
Recommended to be done in discussion with others.
QUESTION
YOUR ANSWER
Define “black box” term as used in science and engineering.
In science, computing, and engineering, a black box is a device, system or object which can be viewed in terms of its input, output and transfer characteristics without any knowledge of its internal workings. Its implementation is "opaque" (black). Almost anything might be referred to as a black box: a transistor, an algorithm, or the human brain.
Define “potting” term as used in electronics engineering.
In electronics, potting is a process of filling a complete electronic assembly with a solid or gelatinous compound for resistance to shock and vibration, and for exclusion of moisture and corrosive agents. Thermo-setting plastics or silicone rubber gels are often used.
(the rest are hands-on problems that can be done only in the class so make sure you start them the latest 30
