Gas station without pumps

2020 August 17

PteroDAQ installation video

Filed under: Circuits course — gasstationwithoutpumps @ 21:52
Tags: , , , ,

As part of my lecture videos for the first half of the electronics course, I’ve created a video on installing PteroDAQ:

and put in the playlist Applied Analog Electronics Part A.  The instructions are only for macos, but similar steps are needed on Linux and Windows machines.

2020 August 9

Videos for Fall done!

Filed under: Circuits course — gasstationwithoutpumps @ 09:35
Tags: , , ,

I think that I finished the videos for BME 51B last night—53 days before classes start.  There are 49 videos totalling 11 hours and 49 minutes (averaging 14 minutes, 28 seconds).

So far, only one of them has had the captions edited (https://youtu.be/s36BWhteeho), but the student doing the caption editing is beginning to get the hang of it and I expect the caption editing for subsequent videos to be done more rapidly.  The process is somewhat simpler than I expected, as we don’t need to do anything with time stamps.

  1.  Download the auto-generated transcript of the video using https://downsub.com/, which can provide the transcript in a simple text format without time stamps.  For some reason, YouTube does not provide an easy way to get this with their native interface—only providing a file in VTT format, which has lots of duplication of words in order to simulate scrolling.  The VTT format is much richer than the simple text format, but very hard to edit to correct bad line breaks and incorrect punctuation.  (I saved the VTT files, in case I need to restore the autocaptioning, but I don’t expect to use them.)There is a way to get the transcript on the native YouTube interface, but it involves screen-scraping and doing a cut-and-paste to a new file.  The downsub.com download just needs the YouTube URL and keeps the title of the video as part of the file name, making a much more usable interface.
  2. Edit the text file, keeping all lines to 45 characters or fewer.  The point of the editing is to correct mistranscribed words (there were two or three in a 20-minute video, and for one of them even the student couldn’t figure out from my mumbling), to eliminate verbal glitches, to correct punctuation, and to put the line breaks at semantically meaningful places (where possible) to make reading the captions easier. Music at the beginning and end should be labeled as “[Music]”.
  3. Upload the edited transcript, as described in https://support.google.com/youtube/answer/2734799?hl=en&ref_topic=7296214 and https://support.google.com/youtube/answer/2734796#upload.  One step seems to be missing there—the upload silently failed the first time I did it, with YouTube still showing the auto-generated captions the next day.  I tried again, deleting the autocaptions when uploading the edited transcript file, and that seems to have worked.

The student hired by the university does steps 1 and 2.  I do one more editing pass over the transcript, correcting any places where the student was unsure of the transcription and looking for punctuation errors (mainly comma splices and hyphenation errors).  The comma splices are a natural result of spoken speech not being obviously broken into sentences—run-on sentences are a common speech pattern.  Judicious punctuation makes the captions easier to read correctly without changing the words of the utterances.  On the first video, I fixed half a dozen punctuation and capitalization errors, corrected one word that the student was unsure of, and corrected another phrase that YouTube had mistranscribed and the student had not caught.  It took me much less time and pain to do that final editing pass than it would have to do all the editing, so it was definitely worthwhile having the student do the initial editing.

I have not yet estimated how many videos I’ll need for BME 51A for the Winter, but I think that there will be closer to 20 hours of video than the 12 hours for BME 51B, so I don’t think I’m halfway yet through the whole course. I’ll probably not quite have finished them by October 1, when Fall classes start, but I might be able to get them done before the grading load for BME 51B crushes me.

I’ll also need to do some videos that won’t go up publicly on YouTube: 10 quiz solutions each for BME 51A and BME 51B.  I’ll probably also do an intro video for each course, calling student attention to important parts of the syllabus—the intro videos may go up on YouTube, but not be part of the playlist.

I’m probably going to rename the Applied Analog Electronics playlist to Applied Analog Electronics Part B, and create a new playlist Applied Analog Electronics Part A.  That will make it easier for students to find the videos they need, and it will make it easier for me keep the videos in order—it is much easier to add a new video at the end of a playlist than to add it somewhere near the beginning.

2020 March 27

Day off today, planning sabbatical

Filed under: Circuits course — gasstationwithoutpumps @ 22:47
Tags: , , , ,

Today was a day off for University of California, celebrating Cesar Chavez Day, though the official day for that is next Tuesday March 31.  I did a little undergraduate director work via e-mail, but mostly took it easy today.

Trader Joe’s

I started the day by bicycling to Trader Joe’s to take advantage of their first hour for seniors (I’m over 65 now, so I qualify, though I don’t think I’m at particularly high risk). The setup was that they had two lines—one for seniors and one for others, allowing people to self-identify to choose which line to join.  The cart handles were being cleaned between uses and customers were getting their hands sprayed before being let in.  They were regulating the number of people at a time in the store, but the line moved fairly quickly, as people were not lingering in the store.

Trader Joe’s has always had super-wide aisles, so social distancing in the store was easy.  I quickly grabbed the stuff I had come for (most of my TJ staples: beer, cider, port, chocolate, paper towels, and soap) and checked out quickly so that others could enter the store.  I don’t think I need to go back to TJs for a couple of weeks, as I have at least a 2-week supply now of just about everything that I ever buy there (we got laundry detergent, cereal, and toilet paper a week or two before shopping got crazy).

Mowing lawn

After I got home from shopping (and scrubbing my hands and the doorknobs I’d touched), I got out the electric lawn mower and mowed both the front yard and the back yard.  The grass (and oxalis and wild onions and all the many other plants that make up my “lawn”) had gotten pretty long, but the plants were still soft, young plants, so the mowing went fairly quickly.  I even managed to fill my 40-gallon green-waste container with blackberry vines, ivy, and chunks of the dead rosemary bush.

Having sabbatical  this spring does mean that I’ll probably be able to keep the grass cut this year, for the first time in about a decade.  No 4′-high meadow with 8′ thistles this year!  Removing all the ivy and blackberries, though, is probably beyond me—filling the 40-gallon green-waste container weekly will probably be just enough to keep the current overgrowth from getting bigger, without making an appreciable dent in the 500 square feet covered with with them.

Preparing for sabbatical

I’m going to take this weekend off (sleeping, re-reading fantasy or science fiction books) and on Monday I’ll start working on creating video tutorials for sections of my book. I’m still debating how to do the visuals for the videos: prepared slides, pen on paper with a document camera, white board in front of the computer, or tablet and stylus.

I am not fond of prepared slides as a presentation style, though I know it has become the most common style for STEM lectures, so having a set of slides to bundle with the book might make it more attractive for instructors to adopt.  My lecture style has been more of an improvisational performance, triggered by questions from the students—that will not translate well to videos with no audience, so I’m going to have to develop a whole new teaching style for myself.

I’m looking at a few document cameras on Amazon ($100–$150), though I briefly considered making a stand for my cellphone (which has a 12MP camera) instead.  I think that having a USB-attached camera with a reasonably designed arm will work better with the various software I might use for making the video than trying to jury-rig something with my cellphone, so I’d be willing to invest in the document camera—if writing on paper works for me as a lecturing style.

The closest I’ve come to using that style in the past was in Spring 2000, after I had the bike accident that necessitated removing my spleen.  I had to lecture sitting down with an overhead projector until my ribs healed—I found it much more limiting than my usual large-whiteboard lecture style, as I could not build up an information-rich surface to point back to previous items on, as I had to keep changing pages.  Whatever I do for the videos is going to have the same problem, though, as the screen is a tiny, little window that can only hold one thing at a time.

I’ll probably also have to invest in colored markers if I lecture on paper—I write somewhat more legibly with a broad chisel-tip calligraphy marker.  I’ve only used black calligraphy markers in the past (the Itoya double-header), but I see that the same company makes colored ones in the same style.

I tried a whiteboard in front of my desktop for the last (optional) lecture of BME 51A.  It was not technically very successful—lighting and contrast were problems, as well as the size of the writing on the screen being too small.  I could try a small whiteboard with a document camera, but I suspect that it will not work as well as paper and calligraphy markers.

One big advantage of the document camera is that I can put small objects (like components or breadboards) on the screen easily—I even do that in some of my live lectures.

The most expensive option is to get a tablet computer (e.g., iPad or Surface) and pressure-sensitive stylus.  I’m not convinced that I’ll be able to write all that well on them, and interfacing them to software that let’s me switch easily back and forth between a head-shot camera, a small-parts camera, preprepared images, and the stuff-drawn-on-the-tablet may be difficult.

Of course, if I’m putting together a video, I don’t have the same time constraints that a live remote lecture would have, as I can film each scene separately and edit them together.  Editing takes up a lot of time though, so I’m not sure I want to go that route, rather than recording in one continuous stretch.  (Yes, I know the quality would be better if I spent a lot of time editing, but I’m not sure I have the time to do even quick-and-dirty tutorials on all the topics.)

Another big change for me is that I’ll probably have to work from a script, rather than doing an improv lecture.  That’s because I’ll need to do closed-captioning on the videos if I post them on YouTube, as the automatic YouTube closed captioning is ludicrously bad (see YouTube closed captions are awful), and it takes forever to put in the captioning unless you have a script already prepared.

Going from big whiteboard real estate and an improv style to tiny screens and tight scripting is going to be a big change for me.  It’s a good thing I have six months to experiment with different approaches and don’t have to go live on Monday  like most of my colleagues.

Unexpected consequences

One good consequence of the sudden forced switch to remote teaching is that there has been more discussion of pedagogical tools (Canvas quizzes, document cameras, tablets, zoom, take-home exams, …) among the faculty in the past week than there has been in the previous 5 years.

Unfortunately, all the discussion has been about lecturing and high-volume remote testing, with none about teaching writing, engineering design, or hands-on lab skills, which are the topics that really need attention (but which are probably going to be sacrificed in this quarter’s remote teaching).

2016 April 4

YouTube closed captions are awful

Filed under: Circuits course — gasstationwithoutpumps @ 13:18
Tags: , , , ,

I looked at the automatically generated closed captions on the Oscilloscope video and they were awful—pretty much just word salad. Speaker-independent voice recognition is obviously not a solved problem at Google.

I could not figure out from the captions what the text was supposed to be, so I’m definitely going to have to take an hour to edit the captions.  For your amusement, here are the automatically generated captions (with time stamps removed):

this

results go and circuits lab

truthful

showing this witness during a self-test
internal calibration began to overshadow

while doing this is the oscilloscope
trunk of an actual protest rally we can

make our nation of this gradually goes
to click here to lower celebration

finals where

whatever settings the previous first
layout which is probably not what you

want once it’s finished it off with
oppressed peoples historical back three

people said these are falling also know
what you want

matter whatever the last person in our
class there will help now also passed a

law received

craftspeople a suitable for calibration
single heads because we were so

impressed you’re the slap on a single
figures out what comes out is to view

that clearly see that is where color
associated with it

channel one yellow peril to this
political channel 39 channel for each

row has little to show you which channel
is for example channel two minutes later

colored chance i’m not respecting the
settings now able to accept this coupled

with 30 measures signal felt craft so
this is where signal from this marker

which is just changed it as a compliment
but this month now throws away and easy

going to take the last year which will
just show us that trust is on the screen

like this property

now to see this listing all we won’t be
using that much bandwidth and landlords

are very very important shows little
light switch when she can be set when

one asks the folks at matthews
telescopes for example tax and you still

think so it will bring up the menu by
pressing his body is still scope sent

along acts now here on the same set to
tax

understand same problem check this
before now also watch now deciding where

around his father is cold six hits and
two bowls bowls permission to just see

they didn’t grade office he’s facing
they’re going about two-and-a-half

divisions so too cold for division

viable single with the slower larger
call for example a change is now five

balls for division and we can see the
same no only goes up by one division in

the other direction to one whole
provision

signal goes off you might rather
increased number of major producing

science able to close at present the
many long now playing here next 10

microseconds

horrible for his own vision for vertical
sets for all channels

provision a single all this way for
division last thing they apparently

because the other way to increase I’m
provision shrinking the way we did not

see one single this way every one
division so this is one killers we’re

also do this population 44122 color
calibration on the east coast is

slightly off

is it about fifteen years

channel as well you just said to
channels on here in great numbers if we

wanted to try to channel off push button
again while standing around a nice

things

orders probe is not properly compensated

just get there is very little space
heater which we can trust is a very

small screwdriver slotted over shooed
and other causes around the corner we

get it just right now include role is

channel on it for

which will help us all based on the
sound levels in the road below ground

connection between the microphone
amplifier board here has the microphone

in silver amplifier chip in black and
some connections on the screw terminal

we have power

5 volts red and brown and black it is
very important to always use this

convention for power and ground so that
you don’t actually connector on things

we don’t have the output signal here in
purple and everything is connected to

these heavier bands which have alligator
clips to the power supply we’re not

going to connect our protocol but we
could have to ground lead to the ground

and probably get here to center panel
which is the signal that is a kind of

difficult connection to make now it’s
connected and we can see on the screen

the output of the mic channels now just
a distraction in the range goals

overseas buyer has your rivals lot we
can also notice that occasionally take

notice cause they saw your head

only when the signal go from below 212
above 2.4 liter just this the trigger

man but other than that shows a trigger
which means it is based on a single

going from their low point for both
point to low is actually separate slope

is rising at going global

another option

trick or treating just normal several
times which will only trigger this is

more useful to wear a lot of things that
you don’t know the exact true that many

levels

sure the level at which is to tax low on
the screen

levels for single trigger a tad bit
lower

usually get a trigger but it’s a free
set a closer Trevor so we had a simple

Update 2016 April 6: After about 5–6 hours of work, I got the closed captions fixed, so these amusing automatic ones are no longer on the video.  Editing the captions is even more work than editing the video, so I can see why so many people don’t bother!

%d bloggers like this: