Electronic Design

Bob's Mailbox

Dear Bob:

I really enjoy your pokes at Taguchi and Fuzzy Logic. To further emphasize how out-of-touch our engineering academics have gotten, I offer the following paragraphs for one of your "Mailbox" columns:

"Your critiques of Taguchi Optimization and Fuzzy Logic have been a great service to us engineering practitioners. Do not, however, interpret the dearth of practical applications to mean that these technologies have been less than successful. To the contrary, Taguchi's exuberant lectures to technologically defenseless managers about the hypothetical success of some ill-founded analytic hocus-pocus have certainly succeeded in putting high-priced bread on his table. With similar success, academics armed with Fuzzy Logic have transformed simple, low-gain, well-understood servo loops into esoterica, thereby hoodwinking the taxpayers out of $100K research grants.

More seriously, however, the failure of these promotions to produce the engineering efficiencies they tout points up a much more troubling problem than simple delusion. The academic community has become isolated from the engineering arts they profess to teach. I doubt that 1 in 50 American electrical-engineering professors could design a production-worthy product. They do not know what components and materials are available, what limitations and strengths these products have, what configurations and combinations are most practical, or what manufacturing efficiencies and problems their choices create. In short, all they know is mathematical analysis of idealized circuits----a very small part of the total design task.

Although they clearly lack the wisdom and knowledge essential for success in engineering, academics still wish the prestige of being considered industrial experts in the field their title professes. Just as medieval alchemists sought to concoct valuable gold from an incomplete understanding of chemistry, our modern university alchemists seek to concoct practical designs from an incomplete understanding of engineering. Having only analytic skills, the alchemists' naive and ill-targeted mathematical incantations serve as the modern mortar and pestle.

It is not that we don't appreciate the attempts of our monochromatic university brethren to shed light on the engineering process, it's just that we wish they would have more respect for the complexity of the total design problem."

There, Bob, now how's that for self-control and diplomacy?

JAMES A. KUZDRALL, P.E.

President

Intrel Service Co.

Nashua, N.H.

James, I think that most EE professors can contribute good stuff to a project team----just as most engineers in industry can----even though they are not all good at running the whole project.----RAP

Good Morning Bob,

...I don't think I ever told you about truck 2 (T2). I have encountered various mysteries in electronic equipment, usually small deviations from ideal behavior. I haven't solved every mystery, but usually I have a notion of the cause, such as nonlinearity, or noise or drift, or parasitic L, R, or C. But nothing that needed a magical explanation. That is, except good old T2.

I spent 1974 at McMurdo station, Antarctica. During the summer there are various trucks in the motor pool, but during the winter when there are only 3 permanent experiments, (riometers, cosmic ray counters, and satellite tracking) we had assigned trucks. My predecessors gave me a few tips (they laughed all the way to the plane), but they were most emphatic that I should insist on T2 during the winter.

That was good advice. I was able to start it even on the coldest days. I had to do without T2 for awhile, because one morning when there were only two vehicles moving in the base (my partner in T2 and a fork lift), they tried to occupy the same space at the same time. But we had a good mechanic, an ex-linebacker from USC, who intimidated T2 back into service. This was really fortunate.

I got to McMurdo just before the base was isolated for the winter. When summer came again, about 7 months later, and T2 was back in the motor pool, the guy running the riometer (two dipole antennas that measure RF noise from the sky at various frequencies in the 2-to-40 MHz bands) had been there a full year. He convinced the folks in charge and me that I could look after the riometer for a week while he took R&R in New Zealand (nearest civilization with an airport). He never came back.

Well, the old riometer was automated with relays and RTL logic. Every few minutes it scanned the frequencies and recorded the levels in a multipoint recorder, which was a wondrous mechanical thing that could make marks on chart paper with about 12 different colors. When things worked fine, there would be 12 smoothly varying curves on the chart.

I soon found out that things worked fine for about 30 hours at a stretch. After that, the multipoint recorder started scattering colored marks all over the chart. I never found out what was wrong, because in the process of opening panels and disconnecting cables to get into the thing, it would start working.

It was frustrating. The riometer was away from the base behind a hill to cut down on RF noise coming from the base, so I had to drive a truck out there. Sometimes, the riometer would start working just as I drove up. I could tell by looking at the chart when it had stopped working right and when it started.

Then I noticed an amazing thing. Every time I drove up to the riometer in T2, it started working. No other truck had this effect. After verifying this, I finagled T2 once a day and drove up to the riometer. It worked fine for the rest of my tour. I never did reveal to anyone why I was so insistent on driving T2. Sometimes the bureaucrats wouldn't give me T2, but I had a duplicate set of keys and just took it during the night.

There aren't many trucks that know how to make electronic equipment work. I suppose that T2 had really big ignition noise that somehow reset whatever was going nuts in the riometer, but magic is just as good an explanation.

ROY McCAMMON

3M Test and Measurement Systems

Austin, Texas

Roy, when you are troubleshooting an intermittent problem, an ability to chase away the problem is not necessarily more valuable that the ability to restart the trouble. Right?----RAP

Dear Bob:

I just received the February 7 issue of Electronic Design, and read your column on the relevance of Deming's stand on inspection to the integrated circuit business. Deming has stated explicitly his view of inspection in this field. I quote from page 29 of his book "Out of the Crises," published in 1986 by MIT: "We must note that there are exceptions, circumstances in which mistakes and duds are inevitable but intolerable. An example is, I believe, manufacture of complicated integrated circuits. Separation of good ones from bad ones is the only way out. Calculations and other paperwork in a bank or an insurance company is another example. It is important to carry out inspection at the right point for minimum total cost."

ARTHUR DAVIDSON

Senior Engineer

Westinghouse STC

Pittsburgh, Pa.

Mr. Deming's index said to look for "integrated circuits" on page 31. Those comments were not on page 31, but seem to have turned up later on page 29. Now, what is the explicit definition of a "complicated" IC? A quad op amp but not a 741? A dual flip-flop but not a quad gate? Would YOU like to buy op amps, gates, or transistors that have not been tested? Impossible----nobody will sell you one.----RAP

REUNION STUFF

All Alumni, Alumnae, and Survivors of (Teledyne) Philbrick Researches, plan for a Reunion at 5 P.M., April 20, at the Hilton Inn across from the Philbrick plant, Allied Dr., Dedham, Mass. For details, contact Cruise Director Joe LoSciuto, 510 Grove St., Norwell, MA 02061; (617) 659-4423. If you can't attend, send a letter to Joe. Keep the faith!----RAP

 

Hide comments

Comments

  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Publish