DIY Arduino PCB Pryamiduino (Video)

Addohms video on making a KiCad Triangle.

Pyramiduino KiCad PCB Desgin

Continuing the DIY Arduino tutorial series, this AddOhms episode shows how to create a PCB in KiCad. I make a joke that the original design was a rectangle, which I found boring and pointless. So instead, I designed a triangle to give the board 3 points. Get it? Puns! I am calling it the Pryamiduino. To be honest, I found not having a constraint to be a problem. By forcing a specific board size and shape, many decisions were more manageable.

boring rectangular arduino nano clone

First design – Boring!

In the end, the video ended up more edited than I planned. KiCad is just so finicky and crashy that I could not make a coherent start to finish tutorial. At least, I could not work with a board at this level of complexity. Something simple like a 555 flasher would be easier to show from start to finish. I am planning some immediate follow-ups with quick tips on using KiCad. It is a frustrating suite of applications, but the results can be quite nice.

AddOhms Pyramiduino Show Notes

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When it is time to move away from delay(), it’s time to learn how to properly use millis(). If you’ve had trouble following my millis() examples, maybe a live tutorial will help.

In this AddOhms Livestream, I go through 4 code examples:

1. Blink, the one with delay(), as a starting point.

2. Blink Without Delay, line by line, what is it doing

3. PWM Fading without delay() (and with buttons)

4. Binary counter that uses buttons to speed up and slow down.

Appearance:Live millis() tutorial: AddOhms Live #5
Outlet:AddOhms Voideo Tutorials

DIY Arduino Schematic board and Checklist

Things to consider when designing a custom board, based on an Arduino

DIY Arduino Schematic Banner

One of the last significant steps in a project is designing the custom PCB. This stage means creating a DIY Arduino board that is custom to the application. Two examples of my past projects are BinBoo, a Binary Clock, and Open Vapors, my reflow oven controller.

While working on a project for a friend, I got to thinking; it would be nice to have a checklist for circuit elements to include on a DIY Arduino board. In the early days, I forgot to add a filter cap to AREF, for example.

These tips are based on an 8-bit AVR design, like the ATmega328p chip. You could apply these tips to other 8-bit AVRs. Until now, I have not designed a custom board around a 32-Bit/ARM board. Though at only $16, I would be tempted to just solder the Teensy module directly to my finished board.

Below is a written list of items for a DIY Arduino checklist. If you’d like to see me design this board in KiCad, check out this AddOhms Tutorial.

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What is the Bald Engineer doing?

Caption This!

Bald Engineering Praying

The next AddOhms Tutorial is how to design a DIY Arduino board. What are the elements you need to include in your own circuit design? While editing the video, I ended up on this frame. It looked to me like I was praying. (At one point I was having serious technical issues with my equipment. But it is unrelated to that frame!) On Twitter, my friend Philip had a different take.

You bring the two hemispheres of Plutonium together like this, and then a short while later...

Question: What caption comes to mind when you see this picture? Leave a comment with yours. You can leave a comment by clicking here.

Op-Amp Question

If you can’t think of a caption, maybe you can help with a different question. What your favorite LM741 op amp alternative? I’ve been working on some tutorials and videos on op-amps. I’d like to incorporate something other than the old stand-by.

Watch Archived Video: Unboxing Hackerboxes

Over the past year, I have been a Hackerboxes subscriber. When the first couple arrived, I opened them up immediately. In fact, I got my first ESP32 through Hackerboxes.

Sadly, I got caught up in so many things I stopped opening them causing them pile up. So to close out 2017, I’m Unboxing Hackerboxes live while answering your electronics questions. (more…)

Date:December 31, 2017
Time:09:00-10:00 PST
Appearance:Unboxing Hackerboxes and more Q&A on AddOhms Live

In April 2017 I backed a project on Kickstarter called “Crazy Circuits.” It looked like a cool concept that was well developed, so I even included it in the Baldengineer Newsletter. I do not typically promote Kickstarter projects–unless they are exceptional in some way. I liked the concept of circuits that worked with existing LEGO-sized boards and pieces. Their shipping was a couple of months off, but nothing compared to some Kickstarter disasters. I received my Crazy Circuits kit in November, compared to the promised September.

The product concept is simple enough I could not put the time into a full write-up or an AddOhms Tutorial video. So, instead, I featured it on an AddOhms Live stream. For example, to connect an LED to a battery, just snap in some conductive “tape.” In the video, I am building my first two circuits ever. I do think the ribbon takes a bit of practice. However, as I said earlier, I like that it adapts to existing LEGO bricks rather well.

If you know someone interested in electronics but afraid of soldering, I think the Crazy Circuits kits are an interesting option. The case they come in is nice. (I know, strange thing to throw out there, but I do like the sorting case.)

After the hands-on, which lasts about 30 minutes, I answer viewer questions. These questions cover op-amps, LEDs, and capacitors.

Watch Crazy Circuits Hands-On, on YouTube

Can you use voltage dividers as regulators? What if you add a Zener Diode? In this AddOhms episode, I show what happens when you try to power a complex circuit like an ESP8266 with a voltage divider instead of a regulator. (Spoiler: Get a voltage regulator.) This video tutorial is related to a write up I did recently on Zener Diodes. For questions or comments visit the AddOhms Discussion Forum.

Behind the scenes

A significant change for this AddOhms Episode is that I moved from Final Cut Pro X to Premiere Pro. I also shot the entire video in 4K, even though the output is 1080p. Animations were still done as 1080p compositions. One snag I ran into, the color corrections I applied in PPro, didn’t seem to get exported. You might notice when the breadboard is on screen, it has a very slight yellow tint to it.

I’ve been changing how I produce the videos. It’s shortening the cycle time. The key is that I’m not trying to animate every scene. The amount of work involved is just too much. I animate practically every frame. So in a 6-minute video, that’s just too much.

By the way, there are two easter eggs in this episode. Can you find them?

Voltage Dividers as Regulators on YouTube

Download AddOhms Live iCal Reminder

Sunday September 24, 2017, I will host the 2nd live stream of AddOhms. My first live stream was a test for the technology pieces. I’ve made some refinements and am giving it a second try. For that reason, I’m keeping the topic really simple.

The Agenda for the Live Stream is:

  • Introduction
  • News (3 stories or projects that I found interesting)
  • Op Amps with the XL741
  • Q&A
  • Whatever surprises pop-up.

In the livestream, I’ll be talking about inverting and non-inverting circuits  using an op-amp. But I am not going to use just ANY op-amp. I’ll be using the MASSIVE XL741! (I did a review of Evil Mad Scientist Lab’s XL741 in the past.)

Download AddOhms Live iCal Reminder

Date:September 24, 2017
Time:17:00-18:00 PST
Appearance:Op Amps featuring the XL741 (and Q&A) on AddOhms Live!
Outlet:AddOhms Live

The first part of the tutorial looks inside of a Brushless DC Motor, or, BLDC. Then I show a discrete transistor circuit that can drive one. Of course, you’ll need a Microcontroller like an Arduino to drive it! Lastly, I briefly talk about an ESC.

Overall, a BLDC is better than a Brushed DC Motor (talked about those on #20) because:

  1. There are no brushes to wear out
  2. No sparks when the motor spins
  3. You can get way faster RPMs out of a BLDC.

Check out the AddOhms #21: Brushless DC (BLDC) Motors. Show notes are available here.

2016 Great Year for Enginerds

Top Tutorials from


While many want to call 2016 the worst year ever, I feel that is an entirely undeserved title. It certainly could have been a better year, but it wasn’t the worst that I can remember. For the engineering community, both professional and hobbyist, it seems to have been a fantastic year. My gauge for this feeling is the activity on In 2016, I saw almost half a million sessions contributing over 1.2 million page views. (That’s 98% more people looking at 313% more tutorials compared to 2015.)

Here’s a breakdown of the most visited pages (tutorials) on the site.

Overall Top 5 Tutorials for 2016

First up is a simple list with the most views, across all content.

  1. MQTT Tutorial for Raspberry Pi, Arduino, and ESP8266
  2. Raspberry Pi GUI Tutorial
  3. millis() Tutorial: Arduino Multitasking
  4. Arduino, how do you reset mills()?
  5. Top 4 transistors for your kit

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