Efficiency is overrated: the importance of resilience in classroom tech

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As excited as I get about the possibilities of new technologies and cloud services, one lesson I’ve never allowed myself to forget is the importance of contingency planning. All the efficiency in the world is worth nothing if you don’t also have resilience.

For example, videorecording is incredibly efficient and effective. In principle, on days during which my students give speeches, I could just set up a videorecorder on a tripod, hit the “Record” button, and walk out for the day. However, if the recorder failed, I would be completely unable to assess my students’ performance! There’s no resilience in that setup. So when I do videorecord important student speeches, I use two video recording devices while simultaneously taking fastidious notes. (I also used to have an audio recorder going at the same time, but even I had to admit that that was overkill!)

Current case in point: an ELI student has to give an important presentation later today, but his USB drive containing his PowerPoint file failed. A teacher sent him to me to see what help I could give him. Upon plugging in the USB drive, I saw that the file allocation table had likely been damaged, because the system was unable to mount the drive despite being able to detect it.

I reformatted the drive and began running Recuva on it. As I type this, the process is 54% complete, with an estimated time left of 10 minutes. Here’s the screenshot I took a bit earlier:

There are no guarantees, but Recuva is pretty darn good at rooting out lost files.
There are no guarantees, but Recuva is pretty darn good at rooting out lost files.

Hopefully we’ll be able to get this student up and running! All of his files will be jumbled up and possibly unnamed, but with a bit of luck, we’ll at least be able to find the PowerPoint file.

So to go back to my original point: using a single USB drive is pretty darn efficient, but it’s not so resilient. If I were in that student’s shoes, I would have copied the presentation onto two USB flash drives; I would have made it available online, preferably accessible via a bit.ly URL; and as a last resort, I would have paper handouts of the slides ready to go as well. Tap-dancing due to technical issues is never pleasant, but if you make sure to plan resiliently, you’ll have the peace of mind of knowing that if Plan A doesn’t work, you still have Plans B and C to fall back on.

(Incidentally, this topic reminds me of one of the most embarrassing moments of my grad student career: I made a mistake while photocopying my handout for a presentation. The original printed copy was two-sided, but I absent-mindedly set the photocopier to “one-sided to two-sided” mode, effectively deleting half of my handout’s pages! And the first I knew of it was when someone in my audience raised their hand and said there was a problem with the handout. I learned a big lesson that day: always, always double-check your handouts!)


 

Postscript: The ending to this story wasn’t as happy as I’d hoped it would be. I was able to recover tons of files, but they were all images, videos, and sound files. Recuva did not detect any PowerPoints or other documents. Oh well.

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What kind of dentist do I see for Bluetooth-aches, anyway?

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What was so bad about good old wired connections, anyway? Photo: Library of the London School of Economics and Political Science, public domain
What was so bad about wired connections, anyway? Photo: Library of the London School of Economics and Political Science, public domain

I love Android, but it’s so darn finicky.

To be fair, most of the issues I run into can be blamed on the fact that I like to modify devices and run custom software on them, but I only take it so far. I only run major, stable releases of CyanogenMod, which is the most popular community-supported distribution of Android. And my phone model (Galaxy S3) is one of the most popular Android devices of all time, so that helps to guarantee an above-average level of software support and performance.

Above average isn’t perfect, though!

After running an update recently, I realized that my Bluetooth headphones’ “Play/Pause” button was now only being interpreted as a “Play” button, meaning I couldn’t pause anything. After a bit of research, I found instructions on what to change in a specific system configuration file (/system/usr/keylayout/AVRCP.kl) to fix how the system handles Bluetooth input. Of course, if the phone weren’t rooted, I’d have been out of luck entirely.

On top of that, I realized today that whenever LTE service is available, the phone simply cannot connect to the network anymore. It tries to, but it just hangs indefinitely. I had to force it into no-LTE, CDMA-only mode to at least get a 3G connection in the meantime. I’ll have to flash a new modem on the phone to see if that clears up the issue.

Update: It turns out the LTE problem was carrier-specific. Flashing a custom APN XML file cleared up the issue.

Oh, Android.

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My foray into the world of smartphone/tablet repair

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My Nexus 7 repair didn’t work, but I have the feeling that the tablet was already water damaged beyond hope. It’s possible that a new battery might revive it, but I’m not confident enough in those odds to want to invest in the cost of a brand new battery. They’re quite pricey.

However, I did just successfully replace the battery of an iPhone 5! So that’s good. It was a multi-step process involving a fair bit of disassembly, but everything went according to plan. Getting the old battery out was quite difficult due to the strong adhesive bonding it to the shell of the phone, but after a few minutes of prying, I was able to peel it out.

In retrospect, I probably ought to have taken some photos of the process– but I was primarily focused on just getting the procedure right!

These are the items I picked up recently for working on small devices, including this iPhone repair:

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The bit set is nice for its inclusion of a plastic spudger and pentalobe bits, but the Phillips-head bits don’t run small enough. I still have to use a glasses repair kit to deal with the smallest of screws.

For the second item– I didn’t know that magnetic project work surface mats existed, but now that I own one, I love it. The idea is that you place individual sets of screws/etc grouped together within the frames, then label what they are using a dry-erase marker. The weak magnetic surface keeps stuff from sliding or rolling away. I actually used to do the same thing using pieces of paper or (perhaps bizarrely) our stovetop, since the stove surface is pure white and works well with dry-erase markets.

The magnetic wand has been a lifesaver. It’s crucial for picking up (or finding, period!) the kinds of microscopically tiny screws used in smartphones and tablets.

The ESD wrist strap is kind of basic IT equipment, but I’d never bothered to buy one before.

And the head-mounted magnifier is something I’d originally picked up for soldering, but it occasionally has its uses in working on tiny devices, too.

(One more thing: it’s good to have a strong suction cup. I used one half of the Orbit smartphone mount set, since the ball provides a great, sturdy place to grip while prising a screen off, but can then act as a kickstand to keep the screen readily accessible and easy to grab.)

I would LOVE to get the iFixit Pro Tech Toolkit:

But I really can’t justify it, given how rarely I actually crack open the shell of a device! All that other equipment listed up above COMBINED only costs HALF of what one Pro Tech Toolkit costs. It’s a shame.

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Alas, poor Nexus! I knew him, Google; a fellow of infinite joy, of most excellent pixels!

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My poor Nexus 7
Alas, my poor Nexus 7

An occupational hazard of owning a small, high-tech device is knowing that just one nasty fall or plunge might be sufficient to turn your digital companion into a hunk of scrap metal.

A few days ago, my Nexus 7 had the misfortune of taking a bit of a bath. But all might not be lost! Although the tablet was obviously nonfunctional at the moment I rescued it, there are plenty of stories of devices surviving an accidental immersion once they’re properly cleaned up and dried out.

To that end, I consulted a teardown guide, got the case cracked open, and unplugged the battery as quickly as possible. I did a more thorough disassembly later in the evening, soaked the motherboards in some 90% isopropyl alcohol to dissolve any sediments and drive out any remaining liquid water, and then set everything out to dry for a few days.

I plan to do a thorough dusting with canned air this evening, reassemble the tablet, and try to boot it back up.

I’m learning about tablet disassembly and repair, regardless of the outcome. And if nothing else, this tablet was very fairly priced and had a good, healthy, enjoyable life. I’ve more than gotten my money’s worth.

If it doesn’t boot up, what then? The main thing I’m worried about is the future of the Nexus line. Google I/O came and went without any Nexus device announcements. The oft-rumored Nexus 8 is still nowhere to be seen, and it feels like no one is even talking about the possibility of a Nexus 7 refresh anymore.

According to all the buzz, Google wants to move away from smaller tablets and push more into full-size iPad territory. The problem is that I would really prefer not to get a larger tablet. I loved the Nexus 7 because its 1920 * 1200 resolution is perfect for watching HD video, and its 4.72″ width was just slim enough to fit in my front pocket, even with a leather case attached.

If I do end up needing a new tablet, I’ll have to check the market carefully to see what newer alternatives to the Nexus 7 there may be which preserve the same slim form-factor.

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