Notes on current flow for email lesson 4

These notes are from Lesson 4 of my Free Email Course. Do you know anyone else who would love to learn electronics? Please share that link with them.

Below you can see the circuit we’re currently talking about.

The resistor and capacitor on the left of the inverter make up an RC delay element:

But how does the current flow in this circuit?

What is BeagleBone?

BeagleBone Black on white backgroundThe BeagleBone is a mini computer, in the size of a credit card. Very similar to a Raspberry Pi.

You can connect a mouse, a keyboard and a display – and you’ll have a fully functional computer.

But most people don’t buy it to use as a normal computer…

…so, what is BeagleBone aside from this?

There’s much more exciting things to make from it… Like:

  • Arcade games
  • Advanced robots
  • Your own coffee machine (like Elias did)
  • Handheld gaming devices
  • Home automation systems
  • 3D printers
  • …and much more

Getting Started With Beaglebone Review

getting-started-with-beaglebone-book-coverI just finished reading Getting Started With Beaglebone by Matt Richardson.

I’m working on a coffee-related project where I need something more powerful than just the Arduino.

The BeagleBone with its HDMI-output and whatnot, is perfect! But I had only used it a little bit several years ago. So I needed a brush-up.

I didn’t want a “here is EVERY technical detail of the BeagleBone” type-of-book.

I know that I learn much faster if I start with an overview, then dig into details later on as I need them.

That’s why Getting Started With Beaglebone caught my eye.

BeagleBone Black Getting Started Guide


If you’re new to the BeagleBone, it can seem complex to get started. I’ve put together this BeagleBone Black getting started guide to help you over the first hurdle.

And as you’ll see, it’s really not that hard.

Confused? Check out What Is BeagleBone?

My intention with the BeagleBone Black now is to use it to develop electronics for a coffee-related project. With the BeagleBone, I can add a beautiful touch screen to the project, because it has HDMI output.

I have only barely tried the BeagleBone before, and that was a few years ago. So I’m writing this guide with a beginner’s mindset.

Intel Galileo Projects: Simple DIY Weather Station

galileo-dht11I’ve played with the Intel Galileo a lot lately, so now it’s time to build some Intel Galileo projects!

In this project I built a very simple weather station that records the temperature and humidity and saves these to a memory card.

I’ll show you how to read temperature and humidity from a DHT11 sensor with the Intel Galileo. Then how to save these values to an SD-card.

Getting Started with Intel Galileo

Getting started with Intel Galileo Board

Getting started with Intel Galileo is almost like getting started with Arduino. But with a few twists.

I recently got my hands on an Intel Galileo. But it took me quite some time to get it up and running.

So I decided to write a small guide to show you exactly how I got started with my Intel Galileo.

Circuit Board Recycling

Circuit board recycling necessaryCan you get money for your old circuit boards?

Apparently yes…

Anne Staley wrote to me a while back.

She was very enthusiastic about the environment and recycling. And she asked me if she could write an article on my blog about this.

I answered that it probably wasn’t something for my blog.

But she persisted. And she wrote the article and sent me. And as I read through it, I realized that it could be an interesting thing to learn about. Even as a hobbyist.

It turns out that you can actually earn money on your old circuit boards. Circuit board recycling sounds like a good idea =)

Read the article below:

How To Use Goals To Help You Build Amazing Projects

When I started learning about electronics, I never cared about goal setting…
I had no clue about what it was. As soon as I had an idea, I brought out my soldering iron and started to put things together. Even though that was fun, it wasn’t very efficient. And a lot of the times I never finished what I started…

It wasn’t until several years later that I stumbled upon a technique called SMART goal setting. And it was really a game changer.

SMART goal setting is super useful when you want to build electronic projects. It helps you clarify what you are trying to do. And it makes it much easier to estimate project costs, tasks that need to be completed and time needed to finish the project.

Brainstorming Techniques to Build Mindblowing Circuits

brainstorming techniques list stuff2Sometimes I find myself bubbling with ideas for amazing projects to build!

But unfortunately this is not always the case… Sometimes I just can’t come up with a single idea. I’m just totally stuck. But over the years, I have armed myself with a secret weapon against it. I’ve learned to use brainstorming techniques.

Build A Circuit Efficiently With 5 Techniques

Have you ever had those times where you were really passionate about a project? But somehow you never found the time to continue on it. And before you knew it weeks turned into months and you decided to give up on it… I hate that feeling! Learn the tricks to build a circuit efficiently.

Build a circuit

I can remember several times when I have been in that situation.

  • Do you have a project you have been wanting to work on for a long time?
  • Do you always find yourself too busy to work on it?
  • Do you wish there was a way to spend more time on your project without cutting down on other activities that you appreciate doing?

This is completely normal. I get hundreds of emails every month, many from someone who wants to build a circuit, but can’t because he is too busy.

But what I have found through my own experience and through communicating with people like you is that it’s not about not having enough time.

The Protostack Development Kit

Today I checked out the Protostack Development Kit. This is a board that comes with an AVR microcontroller and the necessary components to get the microcontroller up and running.

Basically, that means it comes with a voltage regulator, some capacitors, an LED, a power connector, and a connector for an ISP programmer.

You can find the board here

Make A Plastic Project Box

A plastic project box is nice to have to make your project look better. This has always been one of my weaknesses. I can make a really advanced circuit, but when it comes to package it, I have some kind of disability.

ADBO - Plastic Project Box for Arduino (laser cut)

Luckily there are some tools out there for people like me.

Here are three methods of making a plastic project box for you circuit:

  • 3D Printing
  • Laser Cutting
  • Modify Standard Boxes

Eagle Autorouter Tutorial

In this short and simple tutorial I am going to walk you through how to use the Eagle autorouter with net classes.

The net classes feature lets you select different widths for each net. This is useful if you for example want your power traces to be thicker than your signal traces.

In this example we’ll set up a new net class for our ground net. And we’ll set the default width for all the other nets.

Scroll down to the bottom if you prefer a video tutorial instead.

Anyone can Build Electronics

The BBC once talked about the maker movement and how building electronics is available for everyone now. And I wanted to follow-up on that, because that is really true. And that is something that I am really passionate about; getting more people to build electronics.

But first, I want to deal with the naysayers.

Creating Eagle Scripts 101

Eagle scripts are text files with eagle commands. You use them for automating tasks such as changing the width of all the traces on a board, changing board size, or drawing a specific pattern.