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dip
sticks
ECE480
Case Histories
-- Case
Herstories --
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The Dip Stick Brothers
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December 1996
This is about two graduating, Electrical Engineering seniors in ECE
480. (not CPEs but EEs) One is a 30 year old WEM (White European Male),
the other is approximately 26 years old and of middle eastern extraction.
Introduction:
Their circuit consists of one modified "Fuzz-buster" Doppler Radar
transceiver in an aluminum housing (waveguide), one 7808 voltage regulator,
and one 741 opamp connected to the detector diode in the fuzz-buster.
(1) The first building of their circuit: they had wire warped the connections
with BARE WIRES SHORTING OUT, in at least six different places. I asked
if they saw anything wrong--they did not! The concept of bare wires touching
eluded/eludes them!
(2) They thought that the (sticky-on-one-side) press-on copper shielding
tape made electrical connection to what ever it was stuck to.
(3) They spent more than two weeks trying to get a 7808 voltage regulator--a
three terminal device--to work?
(4) When measuring the 8 volts from their regulator at the GUNN diode
terminal with one voltmeter lead on power supply "ground" and the other
lead on the diode, they measured 8 volts; and they also measured 8 volts
on the aluminum housing of the transceiver that housed the GUNN diode--which
should also be ground. This was a puzzlement to them.
(5) It was suggested that they use an audio amplifier on the output
of their circuit as a method of testing. They connected a 4 inch, eight
ohm loud speaker across the very fragile detector diode that at best might
furnish tens of microvolts of AF voltages.
(6) They finally connected a battery powered audio amplifier to the
detector diode using a SINGLE 30 gauge wire-wrap WIRE. That's it. No second
ground return wire!
(7) They had never heard of a "shielded cable" or a twisted pair. The
concept of two wires being required for the circuit to work, absolutely
eluded/eludes them!
(8) They were proud
to show me that they had been listening to me about shielding: they had
put a small 1/2" square patch of plastic electrical
tape on the detector (30_GHz) diode terminal. They said, it was
"to shield it from noise." (note: no
exclamation marks follow--not enough file space)
______________________________________________________________
When you read this you will immediately think that I'm exaggerating
or there must have been very poor communications... Nobody could be this
Stupid!
It is all true! "You really had to be there..."
To meet and talk with these guys, they seem like decent (I'm sure they
are), intelligent young men; there is no hint to their absolute incompetence.
When you ask the WEM a question, he immediately looks at his partner
--for the answer? Apparently they have often "partnered" in their various
classes, and they both seem to have the same level of comprehension.
If you told me that they both had a bad drug experience when they were
young--that I would believe. But that doesn't explain how they could get
through 4 years of Engineering and know... << 0.00.
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--------------- Case Histories (Herstories) ---------------
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| 1.. This is about a person (senior) who, having spent ~4 years attending
class, graduated with an Electrical and Computer Engineering degree.
He/she was a member of a group, of three in ECE480, whose project was
the design of the "Coed Panic Button." This Student's part of the project
was the RF portion. I cannot even start to cover this particular group's
many and varied SINS, however, this one Student's "episode with the Oscilloscope,"
is worthy of your time.
His/Her task was to measure a signal on an IC which was in a portable
phone. He/She had a schematic of the circuit. I wheeled an oscilloscope
over to his/her work position, and laid the scope's probe on the table
and walked away. Twenty minutes later I returned, he/she was turning all
the knobs on the scope, and said that he/she was not getting any signal.
I looked down, and the scope probe was lying where I had put it: attached
to the ground clip of the probe was a series of "daisy-chained"
clip-leads to one of the IC's pins; the probe tip was not attached to anything!
I said, "____," you must have a "return" connection in any measurement."
He/She said, "Oh." "Of course!"
I again walked away and returned ten minutes later: this time he/she
had a second connection to the IC: a second set of "daisy-chained"
clip-leads from another pin of the IC to the frame of the oscilloscope;
the scope probe was where I had originally placed it, and the probe tip
was still not connected to anything!
Only one conclusion can I draw: this Student had never used an oscilloscope--ever!
Having said that, it was obvious that that was the least of his/her deficiencies.
At a design review, this same person was asked to draw a simple circuit
that used a transistor shunting a switch which acted as a switch. He/She
had the base grounded, and the collector and emitter connected, one to
the other; he/she didn't know the symbol for either an NPN or a PNP transistor;
and he/she could not explain the circuit's operation--he/she was "clueless!"
Question:
How in the Hell did this person get through 4 years of Engineering
School and end-up Knowing: Absolutely Nothing?
Hint:
This student had long black hair; a lost "please-help-me" look; an
attractive body, and large breasts.
Answer: _________________________
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Progress Assessments, excerpts from:
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| IVHS Group: Student J, Student K & Student L
1.. They have chosen to not take direction from their sponsor, nor their
advisor--me.
2.. All three people work on the same thing:
As a group they work on the same circuit that would normally require
only one designer (as in a lab problem). It's like three people playing
the same violin at the same time--they will never sound any better. If
they each had their own violin, they, each one, stand the possibility of
sounding better--someday.
3.. No global approach.
They did not: first, create a "Shell," and then proceed to flesh-it-out,
i.e., they are working in serial, not in Parallel!
4.. They have completely ignored the OPTICS aspect of this project,
i.e., the very crux of this approach.
5.. They are "playing with fun circuits," at the expense of the project
(as described by their contract).
6.. If they were working for a small company, which was relying on their
work output to stay in business, they would quickly be "brought-up-short"
by management and fired! --if the company didn't go Out of business
First!
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| Progress Assessments, excerpts from: |
| Child Finder Group #1, Student-A
& Student-B
1.. They do not read data sheets, nor do they read texts!!!
2.. They do not document their work: there are few drawings and these
are not up to date.
3.. When you ask where they are, they cannot show you schematics, they
must describe the circuit.
4.. They have not done a global approach: they have progressed in a
serial fashion and at any one time--if asked--do not know where they are.
5.. Examples: a. Student-A built
a PLL with no gain stage in the feedback loop, even though the phase detector
chip had a Darlington pair for that purpose--as all the design examples
in the data sheets show.
b. It came as a surprise to Student-A
that the chaperone's device required a limiter stage in its
FM Receiver.
c. In spite of our many discussions and my suggestions to read up on
the subject (ARRL Amateur Handbook): their layout and building practices
are just adequate for low frequencies, but Fail for system frequencies
(~ 50_MHz to 75_MHz).
6.. When he/she needed to send a signal from the test VCO (75_MHz) he/she
used only one (1) wire: no transmission line.
7.. When their 5 volt regulator (7805) put out only 3 volts from a 9
volt battery, they never questioned it!
8.. Student-A gives the illusion
of competence: however he/she is anything but competent! Student-B
seems--and is--clueless.
9.. Both Student-A and Student-B
have put in as much effort as any group, but have proportionately less
to show for it. ________________________________________
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| Progress Assessments, excerpts from: |
| Automatic Target Group Student A, Student B & Student C
1.. They have, in effect, done almost nothing. They have many ready-excuses--
some valid--most are not.
2.. Student C has spent more than 8 weeks on a single 555 timer circuit
for the shot sound to trigger a mouse port or serial port pin. The
circuit is crushingly simple, yet, to this day he/she has no idea how it
works! The mouse port expects an active low: his/her circuit outputs a
high. He/She will not put an inverter in his/her circuit to correct this
mistake, and will argue the point: his/her solution is to change the microphone.
How-in-the-world did this person ever become a senior in the ECE Department
at NCSU?
3.. Student A, (computer engineering) while playing, crippled the AMIGA's
operating system by moving device drivers, etc. out of the root directory:
"because it looked better." This prevented proper operation of the parallel
port, hence the video digitizer, for many weeks.
4.. Student B is the most vocal about wanting to "get the job done,"
but has done no visible work.
5.. The wake-up call of the last week, has caused them to put in more
effort than previously. It is too-little, too-late!
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| Progress Assessments, excerpts from: |
| Co-Ed Panic Button #1, Student X, Student Y, Student Z
1.. They have left the hardest part until last: the WIRELESS part!
2.. They have spent most of their time and efforts doing the obvious,
an easy cookbook approach to the network: a network is a network. However,
their network does not handshake. They have avoided the real essence
of the job.
3.. Student Z ended up with the Wireless portion of the project. Student
Z is the most clueless person in the group, and maybe in the whole 480
class.
How-in-the-world did this person ever become a senior in the ECE Department
at NCSU? --There's an Echo in here!
4.. Student X is impossible to deal with: he/she is bright, but he/she
will be limited by his/her inability to learn from others--which is not
much.
5.. Student Y gives the appearance of knowing what he/she is doing,
but I've seen no real evidence that in-fact he/she does.
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| Progress Assessments, excerpts from: |
| Hall-Effect Glove Student F & Student
G
1.. How-in-the-world did these people ever become seniors in the ECE
Department at NCSU? --There's that Echo again.
And even more important, why were they ever let in to the ECE program?
2.. Neither knew the difference between insulated and unnsulated wire!
3.. Neither had ever seen a soldering iron, and did not know how to
use one. They both--on two different occasions --grabbed the wrong end
and burned themselves.
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| There are so many many more such Stories: |
| Sorry, I can't finish. --I must go off and HURL! |
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