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
Location:YouTube
Format:Podcast

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 BaldEngineer.com

baldengineer-2016-review

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 baldengineer.com. 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

Continue Reading »

How a Brushed DC Motor works and how to use them

This Addohms Electronics Motor Tutorial goes into the third dimension. Using a 3D model, we show what makes a brushed DC motor, well, a “brushed motor.” (Hint: It’s the brushes!) Then, as usual, we break down two simple ways to control them with a microcontroller like the Arduino. You can use a single BJT Transistor (remember those from #10?), build a discrete H-Bridge to go in both directions, or use a popular H-Bridge chip like the L293D or L298D. (Notice the ‘D’!)

Tutorial Contents

The video starts with a couple of (mixed) motor examples. Do you know what a “stator” or “rotor” is? If not, that’s okay because that’s one of the first things we explain. After that, we add part like the commutator and brushes to make the Brushed DC Motor. After that is control with a transistor and an explosive reason you need a protection diode. 🙂 Then we show how an H-Bridge Works. Lastly, the advantages and disadvantages of this motor type.

You can see the full Brushed DC Motor Tutorial on YouTube or on the AddOhms page.

A couple of weeks ago I wrote about four current flow direction myths. As a follow up to that popular post, I decided to dedicate this month’s AddOhms electronics tutorial video to Current Flow. In episode #19, I tackle the question of which way does current flow.

You might have heard about “conventional flow” and “electron flow.” In conventional flow, we assume that current flows from the positive voltage towards the negative voltage. In digital, the “negative voltage” is usually called ground. However, that’s not how the electrons move nor is it how they carry the charge around a circuit path.

Electron flow is the description of how electrons carry a charge. Which is the negative voltage towards the positive? This confusion is a result of Ben Franklin mistakingly identifying how electrons moved so many years ago. Yet, we have kept the “positive” and “negative” labels as they are today.

The key though is that it doesn’t matter which method you use to analyze a circuit. Electrons move in a closed path. So whether they travel from positive to negative or from negative to positive, doesn’t matter!

AddOhms #19: Current Flow Direction

Check out the full AddOhms Electronics Video Tutorial on Which Way Does Current Flow on the AddOhms YouTube Channel.

Switching Voltage Regulator Tutorial

AddOhms #18 covers the basics of switching voltage regulators

Switching Voltage Regulator - AddOhms Banner

A switching voltage regulator is one of my favorite circuits. In school, they were the first circuits I built where I understood how transistors worked. In fact, they were the first circuit I saw an inductor being useful! Switching regulators are incredibly efficient when designed properly. Of course, this detail about design is important. They are not as simple as a linear regulator, which is basically an IC and two caps.

To understand the basics of a switching regulator, I released AddOhms #18 this week. This is video tutorial dedicated the Switching Voltage Regulator. If video tutorials aren’t your thing, then keep reading for my written tutorial.

Continue Reading »

The latest AddOhms looks at why you need a pull-up resistor when using push-buttons. This video goes into what happens when you leave a pin floating, what a floating pin means, and how the pull-up actually works. You can get more information about the video on the AddOhms Episode page.

This is the 2nd time I’ve made a video on pull-ups. Despite being a single resistor, it can be a difficult topic for new hardware designers to understand. The pull-up video was the first video tutorial I ever made. In fact, the YouTube version uses YouTube’s “stabilization” algorithm, which gives the video a very warped feel.

AddOhms #15 shows improvements in skill over the past couple of years!

Question: What’s another topic that I need to cover in an AddOhms Tutorial? You can leave a comment by clicking here.

AddOhms DVD Volume 1 is now Back In Stock

AddOhms DVD 1 Banner

Want to learn more about electronics and support this blog? Check out Volume 1 of the AddOhms DVD. It’s the first 13 tutorial videos from the AddOhms YouTube channel, plus a second disc of Bonus content.

These DVDs are professionally produced and available from my Tindie Store.

Right now I’ve only got United States shipping setup, so please ask for shipping if you’re outside the US. (Not sure which countries to set up first.)

Buy On Tindie

Most of the major electronic blogs have covered the controversy between Arduino LLC and Arduino SRL. My first deep look into it was from Hackaday’s Arduino v. Arduino. Since it has been covered so well by others, I won’t re-hash the already known facts.

If you want to join in giving feedback to these companies, please tag your posts, tweets, and content with “#OneArduino“.

Click to keep reading and see the letter.

(more…)