Control a CRT with the Raspberry Pi DPI

I managed to send video signals to a Mac Classic’s internal CRT monitor from a BeagleBone Black back in 2016, and it seems like this is a topic that a lot of people are still interested in. A recent discussion gave me the idea to try and do the same thing with a Raspberry Pi, and I wanted to document the experiment in this article.

Continue reading Control a CRT with the Raspberry Pi DPI

How to use Websockets to control an ESP8266 and a Raspberry Pi with a web browser

For a current project of mine, I had to evaluate how high the latency is when using websockets. In my case, I wanted to use a small single board computer as the server and any device, that can run a web browser, as the client. This tutorial illustrates how a Raspberry Pi and an ESP8266 can be used to act as a websocket server that can be controlled with a standard webbrowser.

Continue reading How to use Websockets to control an ESP8266 and a Raspberry Pi with a web browser

Low latency and high FPS camera stream with a Raspberry Pi

I just saw that two very good sources, that both had an article about this topic, have gone offline without an archived version. And because I continued my work on a robot that is controlled by a Raspberry Pi, I had to figure out how to create a low latency and high FPS stream from the Pi’s camera that can be viewed in a web browser again.

Continue reading Low latency and high FPS camera stream with a Raspberry Pi

Raspberry Pi 3G using a Huawei E303 modem and DynDNS (English)

Update: It seems like this method got irrelevant over the years because the Raspberry Pi 4 now seems to detect the correct mode of the USB modem on its own!

Long-time readers of this website might recognize this article. It was the first article, I published on nerdhut. As of today, this is still one of the most popular articles on the page and because of that, I decided to shorten it a bit and translate it to English.

However, the original German version remains online here!

Introduction

Due to my work on a remote-controlled unmanned ground vehicle, I searched for a way to control it anywhere in the world. Because I wanted it to have a high range and reliability, I decided to communicate with it over the internet, which should be available almost anywhere on the planet. Continue reading Raspberry Pi 3G using a Huawei E303 modem and DynDNS (English)

DIY electronic riddle advent calendar

Oh yes, Christmas! It’s almost that season of the year again. And to shorten the time between the 1st of December and Christmas Eve’, I thought about a bit more interesting advent calendar than one, that only has chocolate in it. This electronic advent calendar offers a riddle that you can create for a loved one or a friend and give it to them so they can try to solve it before Christmas arrives. It offers a clue every day and it presents all unlocked clues on a website that runs on the device itself. The only two things it needs to work is a power supply and a WiFi network it can connect to. And the best thing is: It is really simple to build and it can be re-used every year and it can also be used for other occasions (for example Valentine’s Day)! Continue reading DIY electronic riddle advent calendar

How to use a relay module with your Raspberry Pi, BeagleBone or Arduino

Today I’ll just upload a short how-to article, explaining how to use a relay module. Some time ago I bought a dirt cheap relay module for controlling high power LEDs with a Raspberry Pi on Amazon. One of these modules cost about 2$ (shipping included), which is a fantastic price, so I ordered 5 modules. In this very short article, I want to explain how you can use such a module in one of your projects. Continue reading How to use a relay module with your Raspberry Pi, BeagleBone or Arduino

How to use hardware PWM/CLK to get exact timings on a Raspberry Pi

Introduction

This might not be a common issue, that hobbyists run into when creating their projects, because usually the software PWM, offered by the raspberry pi’s RPi.GPIO-Module, is exact enough for dimming some lights or controlling dc-motors. But for real-time and time-critical applications, this is actually an issue: Continue reading How to use hardware PWM/CLK to get exact timings on a Raspberry Pi