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Internet Radio Part 1: by Phil Prosser If you have terrible radio reception in your house or shed, or have been looking for a neat computer-based music player, this project is for you. M y workshop and sound room is in a terrible location for radio reception.. Given that it is clad reception in corrugated iron, an indoor antenna was never going to work. Even a substantial outdoor antenna was not enough to overcome the poor signal level in my area, and I still get terrible radio reception. This is not such a problem when I lug my laptop out and stream music, but that is a bother. Recently, I was working in the shed, lamenting the poor reception yet again, and the irony that in 2025 I get better internet services than radio. As I trudged back inside to get the laptop, the seed of this project was planted. I had some ‘spare’ Raspberry Pi 4B boards and knew how easy they are to set up to stream my favourite stations. The problem was how to package them other than in the tiny Pi cases you can buy. Something that ran off a plugpack and connected to speakers, more-or-less standing by itself, seemed like the ideal solution. Essentially, a modern version of a “boombox”. As I sat in my armchair, wishing I was listening to the radio, my gaze fell on the 3D printer. The answer lay there. So, what were the requirements? It needed to be: • Easy to build • Not too expensive • Based on a Raspberry Pi 4B or Pi 44 Silicon Chip 5 with an audio HAT or USB audio interface • Able to drive speakers to a decent sound level • Capable of Bluetooth streaming as a bonus • Controlled using an inbuilt LCD touchscreen • Able to plug in USB storage devices easily • One plugpack to run the whole thing • No complicated mechanical work • The option of a modest battery would be a bonus Some of you will be thinking that internet streaming services are not exactly high in fidelity. Yes, the bitrate and quality of streaming services varies, and the sound quality from the Raspberry Pi headphone socket is limited. However, given the option of poor, or even absent, radio reception, I figured that average sound quality is better than nothing. Also, a secondary goal of this project is to introduce people to how easy it has become to construct a fully working software platform that can be used to explore Linux and its multimedia capabilities. It has been decades since I used Unix in anger, so I thought it was a great opportunity to brush up. As a bonus, I wound up with a working radio! Australia's electronics magazine Looking over the Altronics website, the following products caught my eye: • The Raspberry Pi 4B (we only need the 4GB version) [Z6302G] • TPA3110 2 × 30W audio amplifier with Bluetooth input [Z6409] • DC/DC converter that can deliver 5V <at> 5A from 8-32V DC [M7832] • 7-inch (178mm) LCD touchscreen with a 1024 × 600 pixel resolution [Z6516A] With these, all we really need is a housing. 3D printing seemed an obvious approach. Of course, if you are handy with timber or metal, there is no impediment to your building this from either of these materials. Note, however, if you want to use WiFi, a solid metal case will reduce your WiFi range significantly. If you really do want a metal case, then you might want to connect to your internet via the Gigabit Ethernet port, or using an external WiFi antenna. If you have ever heard someone say they will “just 3D print” something, that means someone else has done a lot of work to prepare the files they print, or they are underplaying how hard it is to design a complex 3D object. I am still learning how to use Fusion 360, and am definitely no expert. So after numerous hours with vernier calipers and the computer, and quite a lot of muttering and head scratching, we siliconchip.com.au Photo 1: if you have external speakers (or prefer to use them), you can build the Internet Radio like this, with just the centre section that houses the Pi, touchscreen, amplifier and power supply. had a first version of a console for the Internet Radio. It was not perfect, but it looks a lot like the middle section of the Internet Radio in the picture. If you choose to dip your toes into designing 3D objects, Fusion 360 is probably at the high end of packages you might choose. It is used in industry and uses the common “sketch / model” definition process, so any skill you develop on this tool is directly relevant to professional hardware engineering work (hint hint). The free version does everything we need, so this is a great place to start price-wise. A few tips from a true beginner: • Objects are created from sketches. Sketches are fundamental in this sort of CAD system, and understanding that 3D objects are created from and defined by sketches is the most important first step. • Typical operations used in this project were extrusions, cuts and fills from profiles using sketches to create and modify the bodies that make up the Internet Radio. • Sketches are defined on planes; obvious ones are the X, Y and Z planes from the origin, but you can create them on surfaces of objects, allowing you to define things like holes and the text we put on top of the radio. • You can modify bodies, for example, to place chamfers on edges; still, the critical mechanical definitions are in the sketches. • The bodies that we create from sketches remain defined by the sketch. An extrusion of a square on a sketch could create a cube or, if it is long, a bar. If we change the square on the sketch to a rectangle, the body created siliconchip.com.au by the extrusion will become rectangular. There is a lot of power in this approach, but it can take some getting used to. • There are many excellent tutorial videos on using Fusion 360. Getting things to fit and ‘click together’ does require some thought. CAD can lead to a false sense of security. For example, if you want an aperture, like our SD card hatch, to open and close, the actual aperture in the case needs to be larger than the hatch. In the CAD world, without applying design rules and checks, this works with zero tolerance. For our 3D-printed case, we added a 0.25mm gap around the hatch, as the tolerances of the print demand this. This sort of consideration needs to be applied to every surface in our design. This includes things like the LCD screen hole, plus the front and rear panels. We have an Ender 5 S1 printer that has a 220 × 220mm print area; this is the same as the very popular Ender 3, and many other 3D printers. This defined the size of the main case. It just fits the LCD screen, Raspberry Pi and amplifier, leaving room in the middle for a battery if you are creative. We used these limits in our design, and the project assumes you have this print area to work with. Options The original intent was to design a simple internet radio box that plugs into the stereo in the shed. That is exactly what the first iteration of this project was (shown in Photo 1), and it remains a perfectly valid application. It involves omitting the power Australia's electronics magazine amplifier and running the output to RCA sockets. However, once that was complete, we thought, why not make some speakers that can either sit on a shelf along with the main unit, or even attach on either side, turning the unit into a boombox? Additional speakers definitely wouldn’t fit in the print with the main console, but they could definitely be printed separately. If the speakers are to attach boombox style, the height and depth are fixed (they must match the main unit). To make them look reasonable, the width is constrained to be something similar to the height. This is small, but given this is really more about a functional radio than hifi, that’s OK. In fact, once we added some bass and treble boost in the Media Player settings, the Internet Radio’s sound is surprisingly good. But to be right up front, if you want proper hifi, you need to connect more substantial speakers. With that in mind, the Silicon Chip Internet Radio was born. You will note that we have not included an AM/ FM receiver. This might come across as ridiculous, but remember our use case is for environments lacking radio reception. If you want to swap out the Bluetooth module for AM/FM radio, the switch is there, and all you need to do is integrate the tuner and switch to it instead of Bluetooth. 3D printing and supports Now let’s get back to 3D printing. For those of you who are veteran 3D printers, we are sure you are looking at the radio and thinking, “That is a lot of printing”. That’s true, but it also makes the assembly dead easy. February 2026  45 To those experienced in the art of 3D printing, our extreme laziness on the mechanical aspects of this project has led us to designing models for which no supports are required for any of the printed parts. We hate cleaning off supports, so have spent more time designing supports out of the design than we would have spent cleaning them up. That’s great for you, since it means if you print this design, the pieces should all pop off the print bed pretty well ready to use. For the uninitiated, a 3D printer is an additive manufacturing process tool. It lays down, in our case, 0.2mm thick layers of plastic one on top of another. So what happens if you have a feature that does not start on top of an underlying part of the print? The answer is you need to add ‘supports’, which are printed with the only purpose of holding up features in the final design, but need to be broken off and cleaned up prior to using the print – see Figs.1 & 2. Even running our Ender 5 S1 moderately hard using Klipper on the Creality Sonic Pad to optimise print speed, the main case still took more than 10 hours to print, and the speakers not that much less. So with this project you trade patience, and the pleasure of seeing a whole thing come off your printer, against many hours of manual labour. On and off, this print would run over three days or nights for most people. Of course, once you start the print, there is no effort required. Like most projects, we have built more than a few prototypes. Only one problem arose, which was caused by the print coming loose from the bed. This was down to our being lazy and not cleaning the bed properly before starting the print run. We toyed with the concept of including grilles on the speakers. We don’t prefer grilles, but offer three options: no grilles, small-hole grilles and large-hole grilles – see Photo 2. The choice is yours, and they all come out in a single print. Overall design So what does our Internet Radio comprise? As shown in Fig.3, it is an aggregation of off-the-shelf modules wired together. The wiring is not complicated, but as we will describe later, running this from a single plugpack 46 Silicon Chip Fig.1: “Bob”, designed by young Zak. In an additive print process, there is nothing to support the lower extremities of the arms given that a 3D print starts at the bottom and adds layers to build it upwards. Fig.2: “Bob” as the 3D printer would need to print to provide supports to the arms. The supports can be broken off, but they leave messy bits and it is really never as neat as a clean print. does mean we need to pay attention to the ground routing to minimise noise. The user-friendliness of Linux distributions is now so high that rolling out a Raspberry Pi OS (which we will shorten to RPi OS) with inbuilt tools such as LibreOffice and the VLC media player takes only a few button clicks, and is certainly no more complicated that setting up Windows. It just works. VLC media player is ubiquitous and found on every computing platform, and also very well supported. By using VLC, we can get users up and running with some tunes in a very familiar environment, which can be a springboard for them to dip their toes into much more complex or specialised tools. Why didn’t we use a dedicated multimedia centre app? There are many Australia's electronics magazine dedicated multimedia players available, which can install on everything from a Raspberry Pi through to a full PC. We have played with most of the following, and once you are comfortable with the whole Pi bit and have the hardware running, suggest that you might consider them. The reason we did not start with one of these dedicated players is that some of the configuration is quite specific to an individual’s application, and we ran the risk of the project becoming a complicated description of how to configure one player or another. Still, you could consider using: • Moode (https://moodeaudio.org) • Volumio (https://volumio.com/ get-started) • piCorePlayer (www.picoreplayer. org) siliconchip.com.au Photo 2: we prefer to have bare speakers but you can print one of the case options with a grille if you prefer, for a bit of extra protection against curious fingers etc. Photo 3: we have included a hatch you can use to access the SD card, provided the speakers are not bolted onto the side of the case. These programs do not use the RPi OS desktop, which means that if you install them, the Raspberry Pi stops being a generic Linux machine and becomes a dedicated music player. There are some aspects that might make this very attractive to you, though; for example, some of these allow you to control your stereo from a smartphone. We will go on to describe a much more plain-vanilla RPi OS version, which we believe any DIYer should be able to get up and running. More on Linux For any of you reading this who are intimidated by the fact that this is running RPi OS Linux, we assure you that if you start with the RPi OS desktop, you will wonder what you were worried about. From there, you can read and learn a few of the command line instructions and get a feel for how it works. Oh, and have an internet radio and media player in the deal. At first glance, the RPi OS desktop is just another graphical user interface (GUI). If you compare it to Windows, many menus are in different places, but all the expected things are there. The support for this on the internet is superb. If you type a question into Google like, “How do I set up a Bluetooth mouse in Raspberry Pi OS”, you will get crisp instructions on how to do this in the GUI or at the command line. If you are new to Linux, use the GUI and ease into the command line if you need it. We will describe a pretty simple setup, but you can create a much more complex and specialised media centre setup on exactly the same hardware. siliconchip.com.au You could even have multiple different interfaces on various SD cards and swap between them. SD cards are cheap! We would love to hear from those more expert in Linux/RPi OS and the many media centre programs regarding how you set this up to be much better than our ‘minimum viable product’ offering. Initial setup The first thing you should do is get RPi OS running on your Raspberry Pi. While we have made the build easy to put together and update, it is reassuring to know that the Pi is running prior to putting everything in the case. This first requires us to populate a microSD card with the RPi OS software and plug it into the Raspberry Pi. We have made a special hatch on the side of the case so you can change the SD card without disassembling the main case once it is all built (Photo 3). However, if you have screwed the speakers to the box, then you will need to unplug and remove the Raspberry Pi to change the SD card. Power for the Raspberry Pi may come from the specialised Raspberry Pi power supply or a beefy USB-C supply. To set it up, you will also need a keyboard and mouse to plug into the USB ports, any HDMI display, and a micro HDMI to HDMI cable to connect it to the Raspberry Pi. As mentioned earlier, you also need a microSD card. There is a bewildering array of options for microSD cards; the “extreme” ones allow somewhat faster writes, but this won’t affect most users. This card also provides storage for applications and data such as music, so if you wish to store a lot of data on this card, choose a higher capacity device. Fig.4 shows the minimum configuration to get things running. We will keep these setup instructions brief, as there are plenty of tutorials on loading RPi OS on the web. 1. Download the “Raspberry Pi Imager” from www.raspberrypi.com/ software (it is free and just works). 2. Run it. If you are on Windows, you will see a security pop-up; click “allow the app to make changes”. 3. Insert your microSD card into an adaptor to allow you to plug it into your computer. A simple USB to microSD adaptor works fine (some computers, especially notebooks, have integrated adaptors). Fig.3: the block diagram for the Internet Radio. Australia's electronics magazine February 2026  47 Fig.4: the minimum configuration to get a Raspberry Pi running. This can be lashed together on your desk; once everything is set up, you can switch to using the touchscreen and a small wireless keyboard and mouse. 48 Silicon Chip Australia's electronics magazine 4. Click “Choose Device”. Select the Pi board you’re using; we used a Raspberry Pi 4B. 5. Click “Choose OS”. We suggest that you select “Raspberry Pi OS (Other)” for the operating system, then scroll down and select “Raspberry Pi OS Full (64 bit)”, which will install a whole range of applications and tools – see Screens 1 & 2 opposite. If instead you choose the vanilla “Raspberry Pi OS (64 Bit)”, it omits a lot of very handy utilities and tools. 6. On the “Would you like to apply OS Customisation Settings?”, click “Edit Settings” and enter the following (this is not essential, but does mean your SD card is pre-loaded with this detail making setup easier): a A host name that is simple and you will remember. We used “TGMRadio”. b Untick “Set Username and Password”. We left the password blank, as this device is in our locked shed. You might consider this a risk, so we leave this choice up to you. c Tick “Configure Wireless LAN”. In SSID, put in the SSID of the WIFI network you want the Pi to use. Type your WiFi password into the provided box. d Click “SAVE”. 7. You will now be back at the screen with “Would you like to apply OS Customisation Settings?”. Click “Yes”. a You will get a screen saying, “All existing data (on your SD card) will be erased, Are you sure you want to continue”. b Click “Yes”. 8. Wait until the data is written and checked. 9. Remove the microSD card. Now let’s run through the initial boot and getting it all running. Initial boot: 1. Install the microSD card into your Raspberry Pi; connect a keyboard, monitor and mouse and apply power. You can’t do the initial setup using a Bluetooth keyboard and mouse, although these are OK once RPi OS is configured. The operating system initially looks for them on USB rather than Bluetooth. 2. Upon booting, you will be asked for your country and time zone. Put this data in. 3. Then create a username and password if you want to. Keep this as something you won’t forget. siliconchip.com.au 4. If you didn’t set the WiFi SSID and network password in the Raspberry Pi Imager tool, enter them now. 5. Click OK to let the system update itself from the Raspberry Pi servers. This might take a few minutes. 6. Once everything is up to date, click Restart. The system will reboot straight to the desktop. 7. If you have a Bluetooth keyboard and mouse, now is the time to pair them. The Bluetooth menu is at the top right of the screen; click this and follow the prompts to pair your devices. You can now dispense with the wired devices you used for setup. 8. Send sound to the AV jack by right-clicking on the speaker symbol at the top right of the screen and selecting AV Jack. Once you have RPi OS or your favourite application loaded on the SD card, you will be able to update and load music and applications via your WiFi (or wired Ethernet) connection. RPi OS updates itself over the internet, so long-term support for the operating system will be fine. At this point, we can start assembling the case. Screen 1: we recommend that you install a full Raspberry Pi OS; choose “Raspberry Pi OS (Other)”. Overall build and assembly Printing the parts is not at all hard, but will take a while. We used the following settings: • 10% fill • 1.6mm wall thickness • No supports • No build plate adhesion • Speed will be specific to your printer; we were running around 180mm/s • Material: PLA (or whatever plastic you are using) The overall system comprises the following parts, which are shown in Table 1. We used about one reel of filament in total. We suggest you have two on hand as you always run out at exactly the wrong time. With Klipper and our selected print speeds, we saw the print times reduced by around 40%. Of course, the print time will vary from printer to printer. The last two files listed are the plain speaker with a grille built into the print. We don’t think it’s essential, but you might prefer this. It will definitely give your printer a workout. You need to print one each of the files, except that you either print “Internet Radio Final V1.0 - Speaker x.stl” or “Internet Radio Final Speaker siliconchip.com.au Screen 2: next, select “Raspberry Pi OS (Full)”, which will install many useful programs alongside the operating system. Table 1 – Part name Filament weight Est. print time Internet Radio Final V1.0 - Case Handle.stl 35g 2 hours Internet Radio Final V1.0 - Case Rear Panel.stl 69g 4 hours Internet Radio Final V1.0 - Case SD Hatch.stl 2g 8 minutes Internet Radio Final V1.0 – Case.stl 290g 16 hours Internet Radio Final V1.0 - Speaker 1/2 Rear Panel.stl 62g each 3 hours Internet Radio Final V1.0 - Speaker 1/2.stl 255g each 15 hours Internet Radio Final Speaker 1 With Grille.stl 266g 18 hours Internet Radio Final Speaker 2 With Grille.stl 266g 18 hours Internet Radio Final Speaker 1/2 With Grille Large Holes.stl 280g each 18 hours Australia's electronics magazine February 2026  49 Fig.5: the ground circuit from the plugpack input to the audio output jack on the Raspberry Pi is far from clean, so some creative ground wire routing is required. Screen 3: click Yes here to customise the operating system configuration. Fig.6: this is how we will wire everything up once they come together in the case. Details will be in the second and final part of this series next month. x With Grille.stl”, not both (where x is 1 for the left speaker or 2 for the right). We have tested the speaker prints with grilles, but all our work was with the plain speakers without grilles. Aside from the investment in time, the case should be pretty straightforward. As you go, check that the parts actually go together. They did on our multiple prints, but that is using a sample set of one printer. Our printer is not modified or special, so we expect most people will achieve similar results. We have used moderately generous margins and expect that most printers will replicate the end result we achieved. There should be minimal post-­ processing required. Still, if you were to fill, sand and paint this, you could 50 Silicon Chip achieve a real retro ‘silver’ boombox outcome. As well as STL files, the download package contains the Fusion 360 files so that you can modify them. We apologise that our novice approach to the design is indeed naïve. We make it available for what it is worth. Wiring it up We really wanted to use a single power supply for this, which simplifies its use. This also leaves open the possibility of running this from a 3.8Ah or similar LiFePO4 battery. A challenge created by using a single power supply with a buck regulator deriving 5V DC for the Raspberry Pi is noise. By powering the amplifier and the Raspberry Pi from the plugpack, the circuit from the power pack Australia's electronics magazine to the Raspberry Pi ground has noise induced on it, as shown in Fig.5. It might seem that this is fussing over things, but our initial approach with wiring was to hook everything together using the input socket as the star ground point. We were really surprised at the level of noise that resulted. The easy way to eliminate this noise is to power the Raspberry Pi from a separate isolated power supply, which is an option you might consider. If you power the Raspberry Pi from its own plugpack (omitting the DC/DC converter) and power the amplifier from its own plugpack, all the noise problems go away, but you now need two plugpacks to power the system. The alternative is to follow our guide to move the amplifier’s ground siliconchip.com.au Parts List – Internet Radio Screen 4: fill in your preferred configuration on this screen. reference to the Raspberry Pi’s GND output, which helps considerably. It is not perfect, but for a ‘medium-fi’ internet radio, it does the job. To achieve this, we connect the ground for the amplifier to the ground of the 3.5mm audio plug that goes into the Raspberry Pi, and run a ground wire from the 3.5mm connector back to the power supply input. The resulting configuration is shown in Fig.6. 1 Raspberry Pi 4B 4GB [Altronics Z6302G] OR 1 Raspberry Pi 5 4GB [Altronics Z6302J] AND 1 Raspberry Pi audio adaptor (untested) [Altronics D0290] 1 7-inch (178mm) LCD touchscreen with 1024 × 600 resolution [Altronics Z6516A] 1 32GB+ microSD card [Altronics DA0329] 1 microSD card adaptor (required if your computer has no microSD/SD card interface) [Altronics D0433A] 1 8-32V to 5V 5A USB-C DC-DC converter [Altronics M7832] 1 TPA3110 2 × 30W stereo audio amplifier with Bluetooth [Altronics Z6409] OR 1 TPA3110 2 × 30W stereo audio amplifier [Altronics Z6407] 1 15mm diameter knob to suit spline shaft [Altronics H6540] 1 18V DC 2.8A plugpack [Altronics M8951] 2 SPDT solder tail miniature toggle switches [Altronics S1310] 1 2200μF 35V 18mm diameter electrolytic capacitor [Altronics R6207 or R5206] 2 100mm loudspeaker drivers (optional) [Altronics C0635] 1 wireless USB keyboard [J.Burrows KB210 Wireless Keyboard from Officeworks] 1 wireless USB mouse 1 HDMI to HDMI cable (included with LCD touchscreen) 1 micro HDMI to HDMI adaptor (for secondary display) [Altronics P1925] 1 micro Type-B USB to USB Type-A cable (included with LCD touchscreen) 1 piece of acoustic speaker wadding (optional) [eg, open-cell foam from packing] Hardware & connectors 1 2.1mm inner diameter chassis-mount barrel socket [Altronics P0622] 2 2-way vertical polarised headers [Altronics P5492] 5 2-way polarised header plugs and pins [5 × Altronics P5472 + 10 × Altronics P5470A] 1 3.5mm stereo jack plug [Altronics P0030] 2 4mm red captive head binding posts [Altronics P9252] 2 4mm black captive head binding posts [Altronics P9254] 1 HDMI socket to micro HDMI plug adaptor [Altronics P7374A or P1925] 2 right-angle HDMI adaptor [Altronics P7371A] 1 2m length of red light-duty hookup wire [Altronics W2250] 1 2m length of black light-duty hookup wire [Altronics W2251] 1 1m length of green light-duty hookup wire [Altronics W2255] 22 9mm-long Jiffy box self-tapping screws [Altronics H1139 – pack of 25] 22 M3 flat washers [Altronics H3180 – pack of 25] 2 M4 × 16-20mm panhead machine screws [Altronics H3320A – pack of 25] 2 M4 flat washers [Altronics H3385 – pack of 25] 2 M4 hex nuts [Altronics H3380 – pack of 25] 1 200mm length of 4mm diameter heatshrink tubing 1 200mm length of 3mm diameter heatshrink tubing 1 200mm length of 2mm diameter heatshrink tubing 10 100mm-long, 2.5mm-wide cable ties [Altronics H4031A] 12 12mm round adhesive slim rubber feet (optional) [Altronics H0896 – packet of 4] Next month If you’re building the Internet Radio, you can start printing the case pieces in preparation for next month’s follow-up article. It will have the details on wiring up the modules, mounting them in the case, finishing the software setup and getting the SC Radio up and running. The finished Internet Radio has a handy integrated carrying handle. The volume knob is on the top. siliconchip.com.au Australia's electronics magazine February 2026  51