Low-cost, Convenient, Portable Lighting Solution for Video Conferencing

There's nothing worse than bad lighting on a video call or while recording a video. Experts will tell you that you should buy a nice ring light, which provides a nice diffuse glow on your face as you record. However, most ring lights are eyesores on a modern desk and are generally pretty inconvenient, especially if you regularly use a laptop as your recording rig. For example, a good quality ring lamp might require clamping onto the edge of a desk, which might not be ideal for your desk setup. Fortunately, I've found a cheap solution (far cheaper than most ring lights) that does a great job, is super portable, and looks great on a desk.

This Sailstar Rechargable Reading Lamp is great. 

It is cheap (at the time of this post, it is $16.99 on Amazon and has an additional 10% coupon that can be applied), and it has an array of features that are great for any Zoom call or camera session in general. For example:

• 3 Lighting Modes
  (5000K, 4000K, and 3500K – pick your color temperatures for your complexion and camera)
• Continuously dimmable (800 lumens max)
  
• Diffuse disc of LED light (not a point source)
• Flexible gooseneck and weighted base allows for tipping up to vertical
• Uses a rechargeable battery, and so:
• It can be plugged in continuously
• It can be unplugged and moved for the best lighting experience (very portable!)

I don't know how long this little thing will last, but it seems pretty sturdy. My wife has an older version of what appears to be the same OEM product, and it is still going. I have several colleagues who have purchased this one after my recommendation, and they tell me it's working great for them.

Seeing All Canvas LMS Submission Comments in One Place

I hate submission comments in Canvas LMS. Students are given the impression that these are nice ways to send questions or comments to the instructor, but they are too easy to overlook. For example, the Canvas Teacher mobile app will send a notification whenever a student leaves a submission comment, but the notification text is often truncated and so it is impossible to see which assignment was commented on (even if the student commenting is clear). Furthermore, if you activate the notification, Canvas Teacher brings you to the dashboard as opposed to the comment itself and the notification is lost forever.

Today I discovered that in the "Inbox", which otherwise is for Canvas e-mails, there is the additional functionality to see ALL SUBMISSION COMMENTS across ALL COURSES in one place! Simply click on the "Inbox" and then go to the drop down box in the top left and select "Submission Comments" (as shown below). You can then review all recent submission comments and reply to them without even revisiting the assignment.

So now when I get a notification about a submission comment, I go directly to the Inbox rather than trying to hunt through all assignments (and eventually giving up).

 

Advanced Zoom: Using Slides as Virtual Background

There is a beta feature in Zoom (version 5.2.0 and higher) that is easy to miss but can make for a slightly more exciting way to share slides. When sharing your screen, try clicking on the "Advanced" tab (top center) to reveal several useful options:

There is a beta feature, "Slides as Virtual Background," that lets you choose a slide presentation. Sadly, it only supports PowerPoint presentations at the moment. This is strange because it first converts the PPTX to a PDF and then displays the PDF instead (which means your animations and slide transitions will be removed). So it seems like they should be able to support a PDF directly. I am hoping that will be added in the future.

Once you select a presentation, it will display behind you. It shows you a slide advancer (to move through your presentation). It also allows you to move yourself around the slide and re-scale your size. You can do this live, which lets you place yourself next to important features of the slide (or move yourself off of important features). By default, it scales you down and puts you in the bottom right corner.

Again, this will be much nicer when it supports PDF's in general (as opposed to just PPTX). 

CAVEAT ABOUT RECORDINGS: For now, the merged video (showing speaker on top of slides) will only record if you select to record locally. Cloud recordings will capture the unmerged view. I suspect that eventually they will implement this feature in their cloud backend and the merged view will be able to be seen there too. However, at least for now, if you do this and want it recorded, make sure that you record locally.

Reduce Student Anxiety: Introduce them to "What-If Grades" in Canvas Gradebook

Are your students getting anxious and wondering what their final grades might look like under different “what-if” scenarios related to any assignments yet to be graded? A lot of faculty and students don’t realize that the Canvas gradebook supports “What-If Grades”, which allow a student to click on any grade (even ones not posted) and change it to a hypothetical version to see what the hypothetical effect would be on their final grade.

Check it out:

• Canvas Support: How do I approximate my assignment scores using the What-If Grades feature?

Teaching on Zoom: Fixing Problems with Students Joining Authentication-Only Rooms

To help prevent "#Zoombombing" while still allowing for all of the features that, when not being exploited, provide for productive digital classroom experiences, many universities have recommended that faculty turn on authentication-only Zoom rooms for their classes. For most students, this means that they may have to follow one extra click when joining their classrooms that leads them through the single-sign-on (SSO) process and handoff back to Zoom. Unfortunately, this process is not as simple for some students, especially if they already have their own non-University Zoom accounts.

Here are the instructions (also linked as a PDF or a DOCX) I have been giving to my students to help ensure that they access my authentication-only Zoom classroom using their university account. Of course, there are a few small aspects of these instructions that are customized for ASU, but it would be easy to modify the instructions for your institution.

---

Instructions for Accessing Zoom Room as Authenticated ASU Zoom User

To help mitigate problems related to "Zoom-bombing", your course Zoom link may be configured to only allow authenticated ASU users into the room. If you are having trouble connecting to the Zoom class room with your properly authenticated ASU account, you should try following these steps:

1. DO NOT use the normal link to enter the room
2. Instead, go to https://asu.zoom.us/ and then click on the Log In button
3. Once you are logged in to ASU Zoom, click on the "JOIN A MEETING" link in the top right of ASU Zoom
4. Use the Zoom ID: (10-digit code from your instructor; also at the end of course link)
   

These steps are designed to ensure that you are logged in to Zoom with your ASU ID.

If the above steps still do not let you into the room, then you need to open your Zoom app and make sure to "Switch Account" to your ASU account. Follow these steps:

1. Open your Zoom application
2. Click on your profile image, as in the image below, and go to "Switch Account"
   
   
   
3. Select "Sign In with SSO", as shown below:
   
4. Use "asu" as the Company Domain, as shown below:
   
5. Follow the prompts to login to ASU Zoom and return to your application
6. Use your course’s meeting ID (or the normal course link) to connect to the Zoom room
   
   

Those steps should help ensure that you are able to get into the class Zoom room with your authenticated ASU Zoom account.

Teaching on Zoom: Automatic Subtitle Captions on a Whiteboard

In the wake of COVID-19, faculty are looking for ways in which they can extend their original in-class teaching approaches to on-line while maintaining high accessibility.

I recently saw a request by someone using Zoom for whiteboard capability with automatic, real-time captions that have subtitles for the audio. This capability does not currently exist in Zoom's native whiteboard. However, real-time subtitles are available in presentation applications like Microsoft Powerpoint. In addition, Zoom annotations (if enabled) allow a presenter (or anyone in a Zoom room) to annotate any shared screen as if it was a Zoom whiteboard. So I came up with the following solution to the whiteboard-with-subtitltes problem. Note that other variations on this solution exist, but this particular solution was crafted to be the most generalizable and prevent the most conflicts with Zoom and Microsoft competing for access to a single microphone.

Here are a list of steps to make it happen. You can also see the video below if you prefer to see a demo of these steps.

1. Open a Zoom room on a desktop machine that runs PowerPoint 2019 or later (including Office 365 versions of PowerPoint)
• Do not share audio or video
  
2. From the Zoom room, share the desktop that powerpoint will use when it goes into full-screen mode during a presentation
   
3. Start a blank PowerPoint presentation
   
4. Click on the "Toggle Subtitles" button shown in the bottom left corner of the PowerPoint presentation
• You should now see live subtitles being added to your presentation as you speak
  
5. Join your Zoom room from a tablet device
• This time, connect with audio so that your audience listens to you through your tablet presence
• You should see the shared, blank PowerPoint screen on the tablet device
  
6. Use the "Annotations" button in the bottom left of the tablet view to open the annotations
• Note that "Annotations" has to be enabled for your Zoom room
• You can find the setting to enable Annotations in the advanced settings on your Zoom web portal
• When annotations are enabled, anyone can use them, and so make sure you trust your audience
7. Use your tablet (perhaps with stylus) to draw on the white screen provided by PowerPoint as PowerPoint subtitles below your writing
• You can use the eraser and clear (trash can) buttons to get a blank screen
  
8. If you are going to record, I recommend using "Record to Cloud" from the tablet device
• Again, the goal is to take the load off of the desktop machine that is doing the live captioning

Here is a video I put together that demonstrates the above steps:

Pretty analog docs

Lately, I've noticed more hits on my website for documents that I put together for some classes that I've taught. So I decided to collect all the substantial ones and list them in one place. I figured I'd do the same here...

• Analog Electronics Information
  • ECE327 — Electronic Devices and Circuits Laboratory I (I've included lots of information, documentation, and links on this course web page) Some example documents that I produced for the lab:
    • Transistor Basics — Introduces bipolar (junction) transistors and gives schematics for several common circuits.
    • Practical Integrators — Introduces the operational amplifier implementation of an integrator and discusses solutions to practical problems with the circuit.
    • Linear Voltage Regulators — Introduces the Zener shunt regulator and several series pass-transistor regulators based on it. Also discusses practical uses of the LM317 integrated circuit bandgap reference.
      • Voltage Regulators Lab Report Strategies — Gives more analytical details about shunt and series regulators used in the lab.
      • LM317 Regulated DC Supply Quick Refrence — Quick reference on configuring an LM317 as a 10 V_DC regulated supply (with basic capacitive bypassing).
    • Bandgap Voltage Reference Example: LM317 — Explains how the temperature-independent bandgap reference circuit within the LM317 works.
    • Transistor-Based Ramp Generator — Describes two ways to build a ramp generator using a PNP transistor configured as a current source.
    • Current Sources and Ramp Generators — A more complete discussion of ramp generators and current sources. Includes (impractical) operational amplifier implementations as well.
      • Transistor-Based Ramp Generator (Quick Reference) — Short description of two different transistor-based ramp generators.
    • Single-Rail Level-Shifter Amplifiers — Describes several ways of building a level-shifter amplifier when only one power supply rail is available.
    • Dual-Rail Level-Shifter Amplifiers — Describes several ways of building a level-shifter amplifier when only two power supply rails are available.
    • Current Driver for (Infrared) LED — Describes four different ways of building a current driver for interfacing a low-power digital signal to an LED that requires a significant amount of current for operation.
    • Output Filtering Laboratory Procedure — Describes level-shifter amplifier, Sallen-Key Butterworth low-pass filter, and a current driver for an 8 Ω speaker that uses a BJT push-pull Sziklai-based output stage. Also discusses other
    • Choosing an Output for Maximum Power: Impedance Matching — Discusses why maximum power is delivered when a load impedance is matched to its source impedance.
    • Digital-to-Analog Converter (DAC) Lecture Notes — Discusses several sampling, quantization, and modulation issues. Also includes figures explaining structure and function of R-2R ladder and "H" bridge.
    • Part pinout quick references:
      • Bipolar transistors, Diodes, and Electrolytic capacitors
      • MOS switch, GP operational amplifier, CMOS inverter, 555 timer, and CMOS array
      • Zener diodes, NPN bipolar transistors, LM317 regulator, and Electrolytic capacitors
      • 741 and 351 operational amplifiers with specifications and 555 timer
      • Open-collector voltage comparator, GP operational amplifier, JK flip-flop, MOS switch, Diodes, Bipolar transistors, and Electrolytic capacitors
      • MOS switch, MOS-input operational amplifier, MOS inverter, JK flip-flop, Infrared LED, Infrared photosensor, and Bipolar transistors
      • LM317 regulator, GP operational amplifier, Bipolar transistors, and Electrolytic capacitors
  • ECE209 — Circuits and Electronics Laboratory
    (I've included lots of information, documentation, and links on this course web page)
    Some example documents that I produced for the lab:
    • Review of Circuits as LTI Systems — Brief overview of the mathematics and structures commonly encountered when analyzing linear circuits.
    • Sources of Phase Shift — Uses simple low-pass and high-pass RC filters to show sources of phase shift in (electrical) LTI systems.
    • Phase-Shifter Circuit — Describes and analyzes a simple all-pass filter phase-shifter circuit.
    • Lissajous Figures — Describes the use and interpretation of input-to-output Lissajous figures for analysis of linear time-invariant (LTI) systems in the laboratory.
    • Digital-to-Analog Converter (DAC) Lecture Notes — Discusses basic DAC circuit implementation issues. Includes descriptive figure of R-2R ladder.
      
    • Part Pinouts — Gives descriptive part pinouts for several parts used in an introductory lab on analog electronics, including LM741, LM747, 1N914, 1N4148, 2N3904, 2N2222, and Electrolytic capacitors.
• Control Systems Information
  • ECE557 — Control, Signals, and Systems Laboratory (classical control lab)
    (I've included lots of information, documentation, and links on this course web page)

Course web pages, LaTeX, and Mercurial — Oh, my!

I have been assigned to TA yet another different course for the Autumn 2008 quarter. That was a bummer for me because I have been taking instruction way too seriously, and it has been taking up way too much of my time. However, I've been pretty happy with the results. I've been getting flattering praise and very helpful feedback. More importantly for this post, I've been producing lots of revision-controlled content that can be used for reference or as examples.

The four course web pages that I've produced so far...

• ECE 209 — Circuits and Electronics (permanent home, OSU home)
• ECE 327 — Electronic Devices and Circuits Laboratory I (permanent home, OSU home)
• ECE 481 — Engineering Ethics (just a grader here) (permanent home, OSU home)
• ECE 557 — Control, Signals, and Systems Laboratory (permanent home, OSU home)

I've tried to generate lots of reference material all with LaTeX, and I've tried to put the sites together so that everything can be build via standard Makefiles. I've put all of the source code (minus the exams/quizzes) at my public Mercurial repository home:

• ece209 Mercurial repository
• ece327 Mercurial repository
• ece481 Mercurial repository
• ece557 Mercurial repository

In my latest adventure, ECE 209, I'm going to give my students extra credit if they use TeX for any assignments they hand in. So I've put getting-started information at those web pages, and they can use the Mercurial repositories for more working examples.

I'm really a lot more proud of this work than I thought I'd be. I'm actually looking forward to the new ECE 209 class. It's the youngest group of college students I've taught since a long time ago, and I think it will be interesting. Yesterday I went through and got the lab in order. I put up instructive signs about how to use oscilloscope probes and pin-outs of commonly-used ICs. I numbered all of the tables. I added notes to the function generators telling them how to set them for high impedance output termination. Earlier I went through and repaired all of the phase-shifter circuits (out of 16 circuits, only about 4 were working, but the other 12 could be easily repaired with a little solder and/or a new op-amp IC) and added a little instructive page on how they work. Now all that's left is the actual experience that will make me even more jaded and realize that all of that work was for nothing. :)

Meanwhile though... Lots of free LaTeX examples and circuit references. Yay!