Gas station without pumps

2016 May 26

Not so proud of UCSC undergrads this year

Last year I wrote a post, I’m proud of UCSC undergrads, in which I praised UCSC undergrads for rejecting a fee to subsidize the approximately 250 Division III athletes on campus:

  • Measure 62. Athletics Operations Enhancement Fee: Shall the undergraduates of UCSC provide funding for the operations for Intercollegiate Athletics by implementing a compulsory fee of $117 per student, per quarter, starting in the fall of 2015? FAILED: 60.33% No, 39.67% Yes.

This year, I’m not so proud of the students. After enduring an unrelenting propaganda barrage by the athletics staff, the students voted on an opinion poll that just allows them to vote on a fee measure next year:

Would you support a new student fee of approximately $90 per quarter ($270 per year) to retain the current NCAA Athletics program at UC Santa Cruz?
Votes Percent
Yes 3976 63.53%
No 2282 36.47%
Total Turnout 6258 40.89%


On other parts of the ballot, the students voted overwhelmingly to support fees for maintaining the Office of Physical Education, Recreation, and Sports (OPERS) facilities (about 80% in favor of each of two measures), which I approve of—these are facilities open to all students and which encourage students to participate in physical activity, both individual exercise and social team sports.

I’m not so happy with their theoretical support for subsidizing elite athletes—I have no patience for spectators—sports should be something students do, not pay to watch other people do. In the past UCSC students understood this distinction, with the result that intramurals were far more important to students than interscholastic sports.  When I came to UCSC, 30 years ago, there were no NCAA Division III teams—all sports were intramurals or club sports, and students recognized that participation in sports was something one did for pleasure (and paid for, if needed), not something that was a “service” or for the benefit of others.

It makes sense for students to pool their money to pay for services and facilities that many will use, but not to pay for coaches, trainers, and separate locker rooms for the varsity teams (who make up less than 2% of the student body).

I have been bothered by the Admistration’s $1 million a year subsidy for NCAA athletics for the past couple of years (and for next year). That money could have paid lecturers for about 100 more courses, benefiting several thousand students who can’t get into the courses they need.

I was very bothered by the Academic Senate’s response to this boondoggle, actually encouraging the Administration to continue pouring money into something that really has no reason for existing at UCSC, when basic needs like adequate classroom space and sufficient faculty and TAs to reduce classroom sizes are not being funded.

Oh, well, maybe the students will come to their senses when the athletes actually ask for money next year, as they have done in prior years.

(All that said, the UCSC student elections look much more reasonable than the dysfunctional student government at UCSB, which seems to consist almost entirely of political infighting, if the UCSB student newspapers are to be believed.)


2016 May 22

Disappointing class-D amplifier reports

Filed under: Circuits course — gasstationwithoutpumps @ 15:59
Tags: , , ,

I have a huge stack of grading to do this weekend (about 20 new design reports and about 30 redone reports from earlier labs). I was rather disappointed with the reports for the class-D amplifiers, not because the amplifiers didn’t work (they mostly did), but because about 80% of the class is getting a REDO for errors in their schematics, which means I’ll be having to grade the reports again.  I consider 20% REDO an acceptable level, but not 80%.

The most common error in the schematics was one that I had seen a fair amount in previous years: getting the source and drain of the pFETs swapped.  It is a fairly serious error, as putting the transistors in backwards would cause a lot of shoot-through current from the body diode conducting.  Students were wiring their transistors correctly (after some false starts), but documenting their designs wrong.  A number of students also used the depletion-mode instead of enhancement-mode FET symbol, but I consider this a much less serious error (as long as they included the right part number), and would not have triggered an automatic redo for that mistake.

I warned the students about the source and drain orientation repeatedly, both as a class and (in many cases) individually.  I was very careful to point out the convention for the source and drain notation in class and in the book, and they had it on their data sheets as well.  I don’t know what else I can do, other than instituting in-class quizzes, which I may have to do next year.

There were a number of other documentation problems in the reports this week:

  • Using their loudspeaker models, but not including the model in the report.  In many cases, it was clear from their plots that they had screwed up the model somehow, but without any formulas or parameter values, it was impossible to figure out what they had screwed up.
  • Oscilloscope pictures that did not say what the probes were connected to, or had incorrect labeling of the probes. This was mainly really bad lab technique, where they failed to write down what they were doing, and couldn’t reconstruct it from their memories.  That is one aspect of the labs that I’ve not put much emphasis on this year—writing down what they are doing as they do it.  I may have to emphasize that more next year, especially since the labs will be broken up into 4 95-minute sections instead of 2 3-hour sections, which will make memory even more unreliable.
  • Not reporting the PWM frequency.
  • Not remembering to include their bypass capacitors in their schematics. Some students may not have had bypass capacitors, though it was very difficult to get the amplifiers to work without them, as the H-bridge dumps a lot of high-frequency energy into the power lines, which gets coupled back to the comparator and the preamp.
  • Generally bad copy editing.  The spelling and grammar problems in some reports are just common non-native problems with articles, plurals, and verb tense, but a lot of the reports had huge numbers of spelling errors, duplicate words, missing words, comma problems, and incomplete sentences.  I’ll be addressing this problem next year by giving students a bit more time to complete the reports (though that didn’t seem to help on the one report that students had more time on this year).

2016 May 20

2016 T-shirts ordered

Filed under: Circuits course — gasstationwithoutpumps @ 20:53
Tags: , , ,

I’ve just placed my T-shirt order from my Applied Electronics course:

    The 2016 shirt is an exclusive class-only shirt.The 2016 shirt is an exclusive class-only shirt.

The shirt this year has a couple of differences from previous years’ shirts:

  1. The slug now as a beard, at the request of the class.
  2. The shirt is exclusive to the class this year, with “I survived” added at the beginning of the text, again at the request of the class.  In previous years I was willing to let anyone buy a shirt, to lower the prices for the students in the class, by amortizing the setup fees.

I’m also dealing with a different T-shirt company this year, at the suggestion of one of the students.  I’m using BroPrints, a Santa Cruz company since 1994 (or 2000, depending on whether you count the start of the business or their opening a storefront). Their prices are considerably lower than The Print Gallery, who I used last year. I’m hoping the quality is good (the student who recommended them said that she had used them for several different orders and had good durability of the printing).  I stopped using Sports Design after two sets of shirts (one in 2011 and one in 2014) had bad cracking of the printing, and an order was miscounted in 2014.

Broprints has lower setup fees and lower per-shirt charges than the other companies I’ve dealt with, and the order is a little larger this year (35 shirts), so the per-shirt price should be the lowest yet (about $12 a shirt, and $15 for long sleeve).

I’ve now got the slug design as an SVG file as a master, but what I communicate to the printer is a layered Photoshop file (created with Photoshop Elements from an Inkscape png output), with each silk screen mask on a separate layer.  The SVG file is only 85,868 bytes, while the layered Photoshop file is 11,075,976 bytes.  Obviously the vector format of the SVG file is going to be smaller than a 600dpi raster image, but I’ve found that T-shirt companies can’t deal with Inkscape-created SVG files—especially not when I use non-standard fonts like Optima. The photoshop file is quite inefficiently stored even for a raster image, as a PNG file with essentially the same information (except for splitting the different colors into different layers) created by Photoshop Elements is only 201,677 bytes.

2016 May 16

DASL Updated

Filed under: Uncategorized — gasstationwithoutpumps @ 08:25
Tags: ,

Tim Erickson, a statistics teacher, announced in his blog, A Best-Case Scenario DASL Updated. Mostly improved.

The Data and Story Library, originally hosted at Carnegie-Mellon, was a great resource for data for many years. But it was unsupported, and was getting a bit long in the tooth. The good people at Data Desk have refurbished it and made it available again.

Here is the link. If you teach stats, make a bookmark:

It looks like there are a number of good small data sets there, suitable for toy problems in statistics classes.

2016 May 12

Sprockets closed again

Filed under: Uncategorized — gasstationwithoutpumps @ 21:43
Tags: , ,

I reported in 2012 that one of my favorite bike shops (Sprockets on Mission Street in Santa Cruz) had closed without any fanfare, and a couple of months later that they had reopened under new ownership.

Unfortunately, they seem to have gone out of business again—my wife went there on Monday to get a new floor pump for the soda-bottle rockets, and they weren’t there. I don’t know the reason, but I suspect that they were not moving enough product to make their payroll—bike shops are a tough business, and there are two others within 0.7 miles on Mission Street, as well as one downtown (about a mile away).  That doesn’t count the two (or is it three) on the Eastside, just a mile further away, nor the one near the beach, about a mile away.

The City of Santa Cruz can support 7 or 8 bike shops, but only marginally—it is more a labor of love than a profitable business enterprise.  (Note: one bike shop per 7,000–8,000 residents is a high concentration for the US. There were supposedly only 3790 specialty bike shops in the USA in 2015 [], which is a ratio of one shop per 84,000 people. So Santa Cruz is still doing at least 10 times better than the US as a whole.

It will be annoying to have to walk 0.6 miles instead of 0.4 miles to the nearest bike shop, but not a major hardship. I just hope that the circumstances are not as dire as the previous closure of Sprockets (one of the co-owners died and the other decided not to continue the shop without her).

Next Page »

The Rubric Theme. Blog at


Get every new post delivered to your Inbox.

Join 342 other followers

%d bloggers like this: