Archive for the ‘education’ category

Notes on the ham exams

April 26th, 2010

I really like reading KB6NU’s blog.  He is a good writer and he has a positive enthusiasm for amateur radio which balances some of the other outlets I peruse.  But, a recent post (largely sourced from a guest) left me scratching my head.

It’s more or less billed as the foolproof guide to passing the FCC’s Amateur Extra examination for the highest class of license.  I tend to look at the ham exams as having two components:  necessary information to bootstrap your ham operating career (to the next level) and trivia questions that for most purposes amount to hazing.  There is considerable overlap between the categories and once a question loses relevance to the point of being 100% hazing, it should be removed.  Although I was not happy about it at the time, this is why the Morse code requirement was dropped.  (I might add here that the Morse code exam should have been retained for the Extra, but I have my opinions.  Mode-specific examination should also include the “sound card modes” and SSB.  But, I digress.)

So, where is this going?  The point is that anyone who is an active ham should be able to pass the Extra with minimal study.  You need to know the rules and how to hook up your station.  Some of the math formulas are important to help diagnose problems or set up your station.  The rest are trivia and can be memorized.  It’s not rocket science (or brain surgery, as rocket scientists like to remind each other; don’t ask what the surgeons say).

Ok.  Done ranting.

How Things Work

January 3rd, 2010

flying

As a part of my employment, I occasionally have the opportunity to talk to students in the local schools about my work.  I tend to treat these talks as a “choose-your-own-adventure” for the students, weaving some of my stories and demonstrations into the discourse along the way.  The students love it because they are participating; the host teacher and I don’t get bored hearing/saying the same thing over and over.  It’s a win-win for everybody.  Plus, I get to explore the creativity, imagination, and mental models of the students.  This is one of those stories.

About a month ago, I was talking to some 8th graders about electromagnetic radiation and radio.  When we were talking about the speed of light, I asked the class if anybody knew how GPS works.  One student raised his hand and I called on him.

“You type in the address of your destination.  Then, a satellite moves over that spot and it directs you in.”

These answers always surprise me.  “If there was a satellite for every GPS user, ” I asked, “how many GPS satellites do you suppose that there are?”  He speculated that there had to be quite a few.  Then, I asked, “How much do you suppose a satellite costs?  Do you think that would be cost-effective?”  The discussion continued for a minute or two until we converged on the time-of-arrival method.

Later, I was reminded of watching the movie Enemy of the State with my dissertation advisor when we were on a field installation trip.  We chuckled when a spy satellite was repositioned to track Will Smith’s character.  It’s a good movie, but it’s a bit fanciful at times.  The movies might be the most education the average person gets about satellites—a sobering thought.  On the other hand, there are dozens of things (such as biology, I tell my wife, who did her B.S. in biology) that I treat like black boxes.  There’s just too much to know about to have specialist understanding of it all.  How much is enough?

Since today is Epiphany Sunday (the day that celebrates the magi visiting the baby Jesus) in most Christian churches, I also add the following:  A week ago when we were home for Christmas, I was telling Dad how I always enjoy questioning students about how technologies they take for granted operate to cultivate their creativity and curiosity.  I mentioned the model of the GPS satellites hovering over destinations.  He quickly replied, “Well, that’s how the wise men found Jesus with the star, isn’t it?” These people keep me on my toes!

Hacking Engineering Education

October 25th, 2009
Bell System Manhole Cover

Bell System Manhole Cover

While browsing my local public library a few weeks ago, I stumbled across the book The Best of 2600: A Hacker Odyssey by one Emmanuel Goldstein.  Despite my own youthful adventures (perhaps chronicled in a future post) with computers and networks, I never got into reading 2600, probably for the better.  But, the book represents the best of the magazine and it’s worth reading through more mature eyes.  Why?

The hackers are playful.  They are creative under duress and with limited resources at their disposal.  They tell stories.  They share mental models of the networks they’ve compromised.  They are the explorers of the networked world.  They are social—they understand that networks connect people.

Of course, this assessment glosses over the criminal and arrogant aspects of hacking.  But, the concepts of exploring, building, and sharing knowledge and models are valuable skills for the innovators of tomorrow.  Perhaps we can learn something from the hackers?

Reading other peoples’ poetry

May 17th, 2009
Mobile Carwash, San Juan, PR

Mobile Carwash, San Juan, PR

This entry is dedicated to my brother Seth, who recently bemoaned his declining creativity.

Seth makes a lot of interesting points about things that may or may not have affected his creativity—resource-poor, idea-rich; lack of peer pressure (this one is brilliant, by the way); risk-averse grown-up life; personal disorganization; time-poor; adverse affects of education; etc…

I would like to counter that none of these things necessarily impede thinking creatively, although they might impede acting on that thinking to various degrees. At some earlier point in my life, an English teacher proposed that in order to be a good poet, you had to read other peoples’ poetry. I scoffed at the idea at the time. After all, poets disregarded normal rules of communication. What did it matter that you read anyone else’s work?

It turns out that it matters a great deal. Poetry forces you think about things in a different way. For me, the idea of poetry is fascinating: a “word bargain,” as another teacher once described it. But, have you ever read poetry? It’s like medicine: it might be good for you but they can’t hide the true flavor. I digress. The good news for scientists, engineers, designers, tinkerers, and people who just don’t read, is that we are surrounded by wonderful poetry written on everything we see and do. We must merely notice it and read it.

Carry a notebook, carry a camera, look with a critical and curious eye…

Are you reading other peoples’ poetry?

About the photograph: A mobile carwash system at Parque Barbosa in subbarrio Ocean Park, barrio Santurce, San Juan, PR. The red van contains a large polyethylene water tank and a pump. What problems does this solve? Create? Note locally-available materials. Definitely OPP.

» Read more: Reading other peoples’ poetry

Resume of a Master Dumpster Diver: the Early Years

February 21st, 2009
Dumpster

Dumpster

With transition imminent in our lives, I have begun packing up some of my things that I don’t use much right now. It’ll save some time and headaches when we finally figure out where we’re going and begin the moving process. Coincidentally, my good friend Matt recently moved cross-country and elected to dispatch the majority of his tinkering resources via Craigslist. You see, Matt and I share a common vice: we are master dumpster divers.

I was reminded of this reality as I have been trying to center myself with respect to what’s important in life last week week. I have a lot of stuff, frankly, an embarassing amount of stuff. And, although I use a surprising amount of it, I really don’t need it. But, this post is about collecting the stuff, not getting rid of it. I’ll save that for a later post.

As I began sifting through some of the goodies tonight, a confluence of thoughts began to swirl in my head. I’ve had resumes and vitae on my mind for quite a few months now since I’ve been looking for employment (if you hire engineers or scientists, particularly for RF/signal processing/remote sensing/upper atmospheric/space research and development, I’m your man). And, I was poking through the rubble of my home “office,” which is actually my office, hamshack, and workshop, plus Sarah’s desk and books and the place that Sarah and I cram stuff into when company comes. Suddenly, it hit me: my entire resume can be read through my collection of odds and ends.

Dumpster diving, to borrow the analogy from Nelson Muntz, is like “kicking butt” in the sense that it might not involve any kicking at all. Likewise, you have to get to the stuff before it gets to the dumpster. This is the first rule of dumpster diving: Know who to ask, how to ask, and when to ask. The second rule is don’t get greedy. I learned both of these rules at a tender young age.

You see, the house I lived in between the ages of three and nine was next to the Village of Millersburg’s street department garage. Of course, this was a great boon for a child of my age to see all of the equipment and workers coming and going. Mom and Dad may remember this story differently; but, this is my recollection.

Although I was fascinated by all aspects of construction work, the one thing that I obsessed over more than anything else was signage. Some kids are experts on dinosaurs, I was fascinated by road signs. I coveted the road sign poster on the wall at the BMV. Mom had inquired about obtaining one for me to no avail. The other thing I coveted was a road sign or two of my own. A friend had a stop sign in his room; but, I was looking for something more exotic, maybe a yield sign. My poor mother worked some connection she had at the Street Department to get a discarded sign. She told me that we could go down to the sign depot and pick one out in the morning, which was probably a mistake.

I rose particularly early the next morning and, after locating the sign depot, collected a few signs for myself. When you’re a kid, street signs don’t look big and heavy on their posts. But, when you get up close, they rival your personal geometry. So, I left a trail of signs I couldn’t carry back up to the house. I don’t remember the details of what happened next, other than that we had to return all of the signs and get “approved” ones. I hope somebody thought it was funny; goodness knows I learned a lesson that day about the difference between dumpster diving and theft of city property.

A few years later, Mom had an antique dealer come through the barn behind the house and the signs caught his eye. She let him have them for a song. I was incensed at the time, although in retrospect, it was probably better to not profit too much on them.

The basement of the Inventor’s Hall of Fame once hosted an area where kids could dismantle old hardware. We were fortunate to visit when some racks of AT&T Long Lines hardware had been recently donated. I think I carried a half-dozen plastic sacks of relays, waveguide, transistors, meters, and other assemblies out of there that day. Although I have sifted through most of that by now, the juiciest pieces still remain in my inventory, ready for use. I still don’t think that the docents knew what hit them when the budding master dumpster diver rolled in.

Although I dabbled off and on in the barter of used electronics and such in high school, the dumpster diving began in earnest again in college, where I met guys who weren’t afraid to actually climb into real dumpsters to fish things out. Those were good times. Most of the stuff we pulled out of the dumpsters was building materials, which we used to spruce up our living spaces. Blocks from a demolished (the Young Building of Philosophy and Relgion, a grievous sin against architecture and HVAC) academic building allowed us to put an “upper deck” couch behind the regular couch in our apartment for stadium seating. This was great for watching movies, or at least watching my roommates play Mario Kart 64 with their pharmacy notes on their laps…right.

One of the other great successes was DuddiNet and the Tower of Power. I dragged an 8-foot relay rack (rescued from the scrap heap at a summer job) into my dorm room and filled it full of computers and networking equipment. I asked the university IT people if they had any leftover rolls of CAT5 cable and they gave me as much as I wanted. We pulled our own network in the dorm. At that time, the dorms were 10baseT with hubs. So, it was a real bottleneck if you wanted to move some data (use your imagination here) around. We put in a private switched 100baseT network that connected four rooms on two floors.

In more recent years, I’ve scored some terrific stuff just by paying attention when spaces are being cleaned-up. For instance, that’s how I got my HP vector voltmeter and my oscilloscope. And, indirectly, through Dad, it’s how I got some more Greenlee punches and a set of metal-marking stamps. Anyhow, in order to protect “sources and methods,” I’ll decline from disclosing too many details about my more recent activities…I haven’t swiped anything from a forbidden dumpster, though. Promise.

» Read more: Resume of a Master Dumpster Diver: the Early Years

Playing Pool: Implications for Engineering Education

November 4th, 2008
3 ball

3 ball

As I have written before (in the old WordPress version of the blog which I will eventually import into the present one), I have spent about the last six months learning to play pool. This has been a fascinating experience.  We have a player in our league who is almost always disruptive and socially a misfit.  But, he’s a phenomenal shooter.  He throws three sheets to the wind, takes absurdly low-probability shots, and makes them with frightening regularity.  Why?  I suspect it’s because he not only has the skill to make shots, he’s confident that it’s the right shot to take.  In the Scientific American article The Expert Mind, Philip Ross quotes chess master José Raúl Capablanca as saying, “I see only one move ahead, but it is always the correct one.”  This is also the root of the “don’t second-guess yourself” on standardized tests and the thesis of Malcolm Gladwell’s book Blink.

It would be hubris to suggest that confidence alone yields success (look no further than the White House for a counterexample).  However, the combination of experience, analysis, and confidence, act in synergy to produce results.  The challenge is to create an environment or a curriculum that prepares confident students without watering-down the process.  Confidence in engineering education is not limited to simply being confident that you can solve a given homework problem.  Confidence is understanding how you and your education fit into the engineering process.

Perhaps the most important take-home lesson for engineering educators is to subject yourself to humbling learning experiences from time-to-time.  This would make all of us better teachers.

» Read more: Playing Pool: Implications for Engineering Education

Design Matters: Donald Norman

October 29th, 2008
Don Norman slide

Don Norman slide

Donald Norman spoke as a part of the Design Matters lecture series at UIUC on Tuesday. Here are a few notes from his talk.

The traditional design approach creates a one-to-one mapping between user(s) and a machine or service. However, it neglects the environment. One particularly egregious example is what Norman calls “machines that moon us.” For instance, computers are designed to look good from the user standpoint. However, if the back of the computer faces the customers or a glass wall, more people can see the mess of wires behind the computer than the well-designed part.

“Social signifiers” are trails that people leave behind. For instance, if we arrive at a subway station and the platform is full of people, it is likely that we are early for the next train. On the other hand, if we arrive and the platform is vacant, it is likely that we are late. Fascinating.

Organic processes tend to be asynchronous. Therefore, waiting is unavoidable in the real world. The goal is to make the wait interesting and engaging for the user. More on this at a later date.

In other news, two interesting Design Matters lectures are on the horizon. David Goldberg of the iFoundry initiative to modernize engineering education at UIUC is speaking on 4 November. The second one is actually someone I considered suggesting to the series but dismissed as a long shot…Nokia designer/ethnographer/anthropologist Jan Chipchase, whose fascinating blog is in my blogroll, is coming on 2 December!

» Read more: Design Matters: Donald Norman

False Precision: A Life Lesson from Tinkering

July 12th, 2008

hp3310a-web.jpg

I’m a tinkerer.  I’ve collected some basic test equipment and tools that allow me to work on many things, mostly electronic and mechanical.  I have a cheap digital multimeter; but, the rest of my test equipment, like the HP 3310A function generator pictured above, is analog.  Unlike digital equipment, where it’s no big deal to add extra digits to a read-out, analog equipment usually offers no more precision in its read-out than it’s capable of resolving.

Recently, I was talking to the guy who was the grader for an RF circuits class I took a few years ago.  He was telling me how amazed he was that students would calculate the required inductance for an inductor to five digits of significance.  And, they would write it in scientific notation: 3.1562E-6 Henries.  We laughed.  Nobody can make an inductor that precisely!  Yet, we can calculate (and often measure) it that precisely.    Tinkering, the process of getting something working, often does not require great precision.  Sometimes that’s easy to forget when you have a powerful computer and a lab full of pricey test equipment.

It turns out that a lot of things in life do not demand immense precision.  Heck, we might be better off without digital precision…

Performance enhancement for the thinking man

April 11th, 2008

Recently the popular news has picked up a story about a paper in the journal Nature from December 2007.  The article invokes a crude online survey of academics and scientists about their use of prescription medications like Ritalin as concentration aids.  One of the respondents thought that it was his duty to be as “productive” as possible during his lifetime of “humane service.”  My diagnosis is an acute case of self-importance.

Medication is often prescribed or taken as a substitute for lifestyle changes.  While lifestyle doesn’t always help, it deserves more credit than it gets.  For instance, a friend from college always used to wait until the last possible minute to complete his assignments.  Invariably, he did as well or better than the rest of us.  He spent most of his time doing whatever it was that interested him at the moment and then blitzed the homework.  Brilliant.  If what you’re doing isn’t important enough to capture your focus, you’re not doing the right thing.

Case in point: contesting with SO2R.  You need contact volume to win a contest.  But, pushing F1 isn’t that interesting after the rate slows.  You also need multipliers to win a contest.  This is hard work; but, it’s more engaging than running.  If you do both at the same time, it increases your overall productivity.  A fundamental shift in strategy produces a performance gain.

Improvement requires effort and creativity, not a pill.

Henry Petroski at Design Matters

March 12th, 2008

Noted engineer and failure analyst Henry Petroski spoke recently as a part of the Design Matters series of lectures at UIUC.   He has distilled millenia of human innovation into the following short sentences:

Perfection does not exist.
Form follows failure.
Criticism leads invention.
Design begets design.
Good betters best.
Problems persist.
Invention thrives.
Technology evolves.

I’m not sure there’s much I can possibly add to that…