Adding radio streams to the cooler with a Raspberry Pi

Using a Raspberry Pi and the program MPD to enhance my audio cooler

Introduction

In my previous blog post I finished my audio cooler. It’s a small cooler with a tiny audio system that nevertheless sounds good. The only way to control the audio is through a wired connection. It would be a nice addition to have some kind of remote control either by WiFi or Bluetooth. While testing the cooler I’ve got the idea to connect a Raspberry Pi A+, that was still unused, to the cooler and stream audio over WiFi to the Pi.¬† This could be useful for a garden party or BBQ where WiFi is available and I don’t want to attach the smartphone to the cooler. In this blog post I’ll share my experience with installation and operating the software needed for this project on the Pi.

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Raspberry Pi A+ (in it’s Pimoroni Pibow case) connected with the headphone jack to the cooler. The Pi has a small Edimax Wifi adapter.

Installing music software on the Raspberry Pi

Since I run the Raspberry Pi headless I use SSH login to the Pi. SSH is available for most operating systems with the notable exception of Windows. I already had Raspbian installed on the Pi so first I updated the OS. Continue reading “Adding radio streams to the cooler with a Raspberry Pi”

Audio system for cooler almost finished

A made a 3d printed enclosure for the audio components that fits in the coolers lid together with a simple console to operate the audio

Introduction

A couple of weeks ago I started to make a tiny audio system for our cooler. In my previous blogpost I described all the audio components that I chose for this project. I wanted the components to be small since I didn’t want to waste too much space in the cooler. With the audio components in hand I could design other parts for the audio system. I needed an enclosure for most of the audio components and a simple console to operate the audio. The parts were 3d printed with my Hephestos 2.

The complete audio system in the lid of the cooler. Most components are placed in the 3d printed enclosure.
The complete audio system in the lid of the cooler. Most components are placed in the 3d printed enclosure.

Continue reading “Audio system for cooler almost finished”

Making a tiny audio system for our cooler (part 1)

I’m selecting components for the audio cooler that I’m going to build. The components need to be tiny to fit in the coolers lid

Introduction

For picknicks we use a small cooler and with the upcoming spring and summer it seems like a great idea to add an audio system to it. Most DIY coolers with audio that I found on the internet are huge. Not only do they have large speakers and amplifiers but they also have a huge lead battery hardly leaving any space for the picknick gear. I want a tiny, one speaker system that sounds nice but is lightweight and leaves plenty of room for the other stuff. I also wanted it nicely integrated in the cooler without too many wires. I therefore started to design and build one.

Choosing the audio components

I started this project by choosing a suitable battery. As stated above lead batteries are relatively large due to their low energy density. Lithium polymer batteries on the other hand have large energy density, four to five times higher than lead according to this source. Prices of polymer batteries are also very reasonable nowadays.

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Lead-acid battery (left) and polymer battery (right) side by side on the small cooler. The much bigger and heavier lead-acid battery has a capacity of 5000mAh (6V) while the lithium polymer battery has 1200mAh (3,7V). The lithium polymer with it’s four to five times larger energy density is therefore perfect for my small audio system.

Continue reading “Making a tiny audio system for our cooler (part 1)”

OpenELEC maintenance

How to update OpenELEC without loosing settings, getting YouTube to work again and creating an OpenELEC backup. Make screenshots in OpenELEC.

Introduction

last year I built a PC especially for OpenELEC. For those of you who don’t know, OpenELEC is a Linux based system with the sole purpose to run Kodi, the all-in-one solution to play all media you throw at it. Because of this sole purpose OpenELEC is very fast, especially on the Intel based system that I built, and very reliable. Over time however some maintenance of the system is necessary to keep the system up-to-date and fully functional. Continue reading “OpenELEC maintenance”

More designing and 3D printing

putting my 3D printer to use

Introduction

The last couple of weeks I’ve been busy mastering 3D modeling programs and bringing my creations to life with my Hephestos 3D printer. In this entry I’ll share some of my creations and how they were made. For 3D modeling I started with OpenSCAD in the beginning of this year and later started using FreeCAD. The reason for using FreeCAD is that with more complex design in OpenSCAD it is easy for me to get lost in a large script. Yes, the learning curve of FreeCAD is steep but eventually it’s easier for me to create more complex models in this program than in OpenSCAD. For simpler models I still like OpenSCAD better. Continue reading “More designing and 3D printing”

Case for a FM-radio (Velleman MK194)

Making good use of a 3d printer

I have a MK194 radio kit from Velleman and turned it into a radio some  time ago. The radio looks pretty cool with all the electronic components visible but the wooden case was awful. I therefore decided to build a new case for it. Of course I want to use my Hephestos 2 printer from BQ to make this case.

First I designed a case in FreeCAD. I use FreeCAD for a couple of weeks now, together with OpenScad, but this is the first design with multiple parts that I create with it. After several iterations I finally decided to have a design consisting of three parts. A box, a support plate for the radio PCB and a lid. The radio fits into the support and the lid which are then screwed onto the box.

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Design for the radio case made with FreeCAD consisting of three parts (the red part just represents the MK194 PCB). I made a nice radius on the lid and the MK194 fits nicely between the support and the lid.

Continue reading “Case for a FM-radio (Velleman MK194)”

Blogger vs WordPress

Should I move my blog from Blogger to WordPress.

My sister asked me to create a website for her business. In all honesty, it’s been some time since I last made a website so I did some research before I started. I quickly found out that WordPress is now the dominating platform or content management system (CMS) as it is called. It’s also completely open source (GPL license) which is a big bonus for me. It therefore didn’t took me long to decide to use WordPress for the website.

While working with WordPress I was impressed by it’s the ease of use and the huge number of themes. Also the support on the internet is excellent. So I began asking myself if I should move my blog from Blogger to WordPress. Continue reading “Blogger vs WordPress”

What to make for Valentine’s day?

Looking for an idea for Valentine’s day. Look no further.

What to make for Valentine’s day? A bare perfboard with a Valentine’s chaser (basically a 555-chip, 4017 decade counter and a handful of leds) doesn’t look too impressive. That’s why I made this heart shaped wooden box with a laser cutter. Both printboard and battery fit nicely into the box. Three bolts, nuts and washers to finish the job.

The file for the laser cutter (.svg) can be found here.

And here is a 3d printer file (.stl) of a little dock for the heart.

 

Assembling a Hephestos 2 printer

Is this 3d printer a good choice for a beginner?

Introduction

While making my projects like the Darth Vader chest box 2.0 I use the local fablab a lot, especially the laser cutter and the 3D printer. It was a bit boring to wait for the 3D print to finish (laser cutting is typically much faster) with not much else to do at the fablab. I therefore decided to buy my own 3D printer. I choose for the BQ Hephestos 2, a sturdy Prusa i3 all metal printer that comes in a kit. Continue reading “Assembling a Hephestos 2 printer”

Darth Vader chest box finished

Most impressive. Obi Wan has taught you well.

The main features of the Darth Vader chest box are:

  • enclosure laser cut plywood (6mm)
  • easy control with four push buttons
  • DIY voice changer circuit with Holtek HT8950A
  • LM386 amplifier
  • build-in speaker
  • audio-in (3.5mm)

When I started the Darth Vader chest box early december 2015 I didn’t expect it would take me almost two months. Finally this week I finished it and I’m happy to say that it works great. For a couple of weeks it was almost finished but there always seemed to be some work to be done. A major problem was that I couldn’t get the 3D printed container for the audio-jack right. I tried it several times at my local fablab but it just didn’t fit. Finally I ordered the container from 3D Hubs and it had a perfect fit. Continue reading “Darth Vader chest box finished”