Retro-Fit a Google Home Mini

Intro: Retro-Fit a Google Home Mini

Give your digital assistant some analogue style by retro-fitting it into an old cassette player or radio!

In this tutorial I'll take you through installing a new-spec Google Home Mini into an old-tech cassette player from the 1980s. Why would you want to do such a thing? Well it gives your home mini a cool retro look, makes it easy to wall-mount it and costs next to nothing. Also fun.

The build is fully documented on YouTube at https://youtu.be/Ys2LJ_-bc0Y and there's a chapter link in each step. Let's get started!

Step 1: Choosing and Dismantling

The first thing to do is find an old radio or cassette player - junk shops and secondhand sales are great for this, and the beauty is you don't have to worry about whether it works! Obviously you want to find one that suits your style and will look good hanging on the wall, but there are one or two other things to consider. The Google Home Mini is about 10cm in diameter and just over 4cm deep, so you'll need to make sure the speaker is roughly the same size and the old case will have enough room.

For extra coolness choose an old unit where you can see the speaker through the grille - this will allow the home mini's indicator LEDs to shine through.

Dismantling video: https://youtu.be/Ys2LJ_-bc0Y?t=216

Dismantling is usually straightforward with an older player, just take out all the screws you can find and pull it apart! The cassette player I used only had about half a dozen screws holding it together, and once the back was off it was just a case of working around snipping wires and removing circuits until the speaker was exposed.

This style of cassette player is ideal as most of the mechanical parts are located away from the speaker under the cassette compartment, I left most of these intact as they were holding buttons & knobs in place. In this case the speaker was held in place by a single heavy wire, stretched between two metal clips - you may find speakers held in by screws and brackets too but either way the Home Mini can still be fitted easily (more on that later).

With all the loose wires trimmed back and the original speaker removed it was time to fit a newer, smarter one.

Step 2: Fitting and Assembly

It was great to test-fit the Home Mini and find it was almost exactly the same size as the original speaker - the next step was to fit it securely in place. I used cable ties for this, threading smaller ties through the original metal tabs that held the speaker then linking these together with a double-length heavy duty tie. It's important to have the speaker firmly fixed to avoid vibrations when music is playing, but also not squished too tight as this could damage the speaker.

Assembly video: https://youtu.be/Ys2LJ_-bc0Y?t=429

I wanted to add another cable tie in the opposite direction just for peace of mind, but the holes in the metal tabs were too small to poke it through - this was easily resolved though, I just fed a couple of old key-ring split rings through the tabs then added the thick cable tie between them.

The cable tie arrangement worked really well in this case, and there's almost always something you can use in an old case to hold the speaker. If your original speaker was held in by screws & brackets my top tip is to replace these with appropriately-sized cup hooks, then you can just thread the cable tie between them as above.

Step 3: Final Touches

When I went to replace the back of the cassette player it just wouldn't fit - the original speaker had been pretty low-profile and the battery holder had been directly above it - those C cell batteries take up a lot of space! This problem was fixed by just chopping out the battery bay from the back of the case with a rotary tool. It made a bit of a mess but as it would be on the wall-hanging side this wasn't a problem.

Final Touches Video: https://youtu.be/Ys2LJ_-bc0Y?t=657

Now that I knew the back cover would fit I drilled a couple of holes in it to make a "keyhole" slot for wall hanging, just a case of finding the middle, drilling a small and large hole and cutting between them with a junior hacksaw or coping saw blade.

Lastly I printed out a cassette tape label in the Google colours to add a bit of extra colour, and added some self-adhesive rubber feet to the back to help absorb any vibration against the wall.

Step 4: Analogue Parts - Digital Smarts

I really enjoyed this project, it only took an hour or so but has smartened up the workshop no end, I'm no longer reduced to listening to podcasts on my phone speaker or messing about connecting it to the stereo when I'd rather be soldering. It's also super-handy to be able to use the Broadcast feature to intercom to the other speakers around the house.

You can get all kinds of mounts for the Google Home Mini online now (even Mickey Mouse) but I think this is at least as practical as the brand-new options with the added benefit of being unique and reflecting your own personal style. You can even flip the orientation of the LEDs in the Google Home app if you're mounting it upside down like this one.

It's a fun & practical entry-level project (gateway drug) for anyone starting to experiment with hacking old tech - the next step from this is incorporating an Arduino or Raspberry Pi to make good use of some of those lovely tactile buttons, as I love to do in my other projects!