Wait, Is This a Rotary Bitcoin Node?
For different reasons I wanted to setup my own Bitcoin and Lightning full-node. I won’t go into the motivation on why you would want to run your own node as this would easily fill up the complete article and others have touched this subject already extensively.
Now the basic setup of a Bitcoin node is quite easy and straightforward. But there’s a ton of additional options to consider in terms of software, hardware, cases, etc. Having seen Umbrel I immediately decided that this was the platform I wanted to use. It has a great looking interface, there’s ongoing development and new updates and at has an active and growing community. Umbrel will run on a Raspberry Pi but what about the other hardware?
Then I stumbled upon an old 1978 rotary phone that I had laying around. It’s actually the very phone my parents used at home when I was a kid and I took it with me a few years ago as some kind of 80’s relic. Having seen creative minds who transformed similar rotary phones into actual working modern-day phones, it now crossed my mind to use this rotary phone as a case for my Bitcoin node. Easier said than done but it just seemed a fun project and it would also allow for my 80’s relic to get a place somewhere in my living room and actually have a purpose rather than just collecting dust.
Step 1 — Cleaning and stripping the rotary phone
I’d never seen a rotary phone from the inside so first I needed to open up the phone to check if all the necessary hardware would be able to fit in. I quickly realized that I was probably the first person since ’78 to see this phone from the inside and I needed to clean all the pieces first. Then I had a closer look at all the internal pieces and decided which ones I could lose in order to make space for the new hardware. This wasn’t too difficult as these rotary phones are made in a time when nobody cared about making the thinnest or smallest phone. The internal pieces are mainly mechanical, neatly organized and easy to recognize.
Step 2 — Ordering the right hardware and cables
Now I had the rotary phone completely stripped and cleaned. Putting the remains back together would still result in the exact same rotary phone on the outside and that was an absolute must for me. On the inside I now had some free space to work with and I figured this would be sufficient for the new hardware to fit in.
On the Umbrel website there’s a list of recommended hardware to be used for putting together a Bitcoin node. That would have been the easiest way but given the amount of free space inside my rotary phone I realized that this simply wouldn’t fit. Main reason was the size of the listed SSD and associated enclosure. And to make things even more challenging I also wanted some kind of cooling for the Pi.
I took some inspiration from other Pi cases on the market that have a build-in SSD mount. Then I compiled a shopping list on Amazon of my own, constantly comparing those items with the recommended items from Umbrel and checking the exact measurement to see if and how these would fit into my rotary phone. I ended up with the following parts:
> Raspberry Pi 4 8GB; I’ve seen people using a 4GB version and that seems to work as well but given the relative small difference in price I decided to go for the 8GB version and be as future proof as possible.
> Raspberry Pi Official Power Supply.
> Crucial P2 1TB 3D NAND NVMe PCIe M.2 SSD; this is probably the biggest difference with the suggested hardware from Umbrel. Given the amount of free space inside my rotary phone I simply need the SSD to be a M.2 model. First I looked into a SATA drive but then Amazon had a great deal on a Crucial for just €70,- so I decided to go with that one.
> ORICO M.2 NVMe SSD Enclosure; just make sure you pick the correct enclose, in this particular case an enclosure for M.2 model SSD’s with a PCIe interface;
> SanDisk 32GB microSD: maybe you’ll have one laying around, a 16GB will do the job just fine.
Additionally I bought:
> Geekworm P165-A; a cooling unit that is small enough to fit into the phone. There’re cooling options out there that do a much better job at keeping the temperature of the Pi low, but for the purpose of running a Bitcoin node this Geekworm unit will do the job quite well. Or at least that was my assumption;
> Cables; both the Pi and the SSD enclosure come with standard cables, but because of the limited space inside my rotary phone I needed a few cables with angled connectors rather than the standard ones.
Total spend on this shopping list including shipping and discounts was €210,78 (~$250). Please check the reference at the bottom of this article for a link to this shopping list including all the exact items.
Step 3 — Test run
Since I didn’t go for the recommended hardware, I needed to test my setup before mounting everything inside my rotary phone. So I followed the ‘how to install’ guide on the Umbrel website, put everything together, crossed my fingers and …. BOOM, works like a charm! That was the green light I needed to continue and now I needed to figure out how to mount all the hardware inside my rotary phone.
Step 4 — Visualizing the end result
This is the point I realized that a rotary phone was never build to become a Pi case some 40 years down the road. Different from standard Pi cases, all the available ports on my Pi will be out of sight and out of reach once the Pi will be placed inside the phone. I needed to figure out if this would be an issue. Theoretically not, but then I would have had to establish a fixed connection for both the Pi power-supply and a network cable. This will limit the ability to move the phone to a different place and to tuck away the cables neatly. So I had no idea how to fix it but I was sure about the fact that I wanted the connectors to be available on the outer side of the phone.
It turned out that this wasn’t such a big deal after all. As mentioned in the parts-list I would already need cable extensions with angled connectors, so now I needed just make sure these cable extensions would be mounted in such a way that the connectors would be available on the outer side of the phone. I could then just plug in the power as I would have done with any other case.
I’m not sure with which the manufacturer of these phones back in the 70s was expecting these phones to connect with, but there’s actually a really extensive and neatly positioned row of port options available at the back of these phones. This is just perfect to lead the internal cables to.
Step 5 — Final prep the phone, hardware and cables
Ok, so now I pretty much had the complete layout of how this whole creation should look like. I now needed to cut away pieces of plastic inside the phone so I could lead the new cables to the appropriate places. I used a small metal saw and a simple box cutter to do the job.
I then mounted the new cable extensions in line with the port openings at the back of the phone. Once in place, these cables had little room to move already, but I then used some glue to fixate them.
Earlier, when I did my test setup, I noticed there was a bright blue led light shining from the SSD extension. And since these phones are not sealed off like modern day devices, I was afraid that there would be a blue glow coming from my phone, specially at dark. There was no way I could just disable this led so I decided to go for a somewhat Mickey Mouse solution and I just duct taped the SSD extension in order to block the light from the led.
Step 6 — Putting everything together
Back in step 2, I had a certain setup in mind. I figured the Pi would not fit crosswise in the phone. Now I have all the hardware at hand it turned out that the Pi actually does fit crosswise inside the phone. Not only that, it almost seems this phone was made to have a Pi fit in as there seems to be almost a perfect fixation for the Pi without having to use anything like screws or glue or whatsoever.
Really important here was to make sure to put the microSD card loaded with the Umbrel OS in the Pi already as the microSD port wouldn’t be accessible from the outside of the phone after everything was mounted together.
The SSD enclosure is obviously not meant to be used as an internal part. Should I have known that the Pi would actually fit crosswise inside the phone, I might have looked into the option of using a Geekworm expansion board (X873) for the Pi on which one can mount a M.2 SSD. This would have replaced the SSD enclosure and that might have resulted in a bit of a cleaner setup but since I went the other direction, I’m not 100% sure if that would fit altogether.
Anyway, I now needed to find a place for my SSD enclosure and I used some free space underneath the dial for that. And again, this almost seemed to fit in naturally and this would fixate the enclosure already pretty much. For maximum fixation I used a small piece of double-sided tape. Again, a bit of a Mickey Mouse solution but this is all out of sight and it just does the job.
Step 7 — Plug & Play
Now I just needed to plug-in the power- and network cable and off I went. From here on I just followed the instructions from the Umbrel website again. And these guys just made it ridiculously simple to setup your node.
Depending on your network speed your patience will now be put to the test as the node will first have to download the complete Bitcoin blockchain which is currently just over 350 GB. This will at least take two days although I’ve seen people mentioning durations up to seven days or even more. For me it was 60 hours on a 100 Mbit/s glass fiber connection. Meanwhile I just played around to see what Umbrel has to offer, linking my node with my wallet of choice and installing additional apps from the build-in App Store.
Final Thoughts
My Bitcoin and Lightning full-node is now running for about 4 months and it does that flawlessly. I’m not sure about other options but I’m definitely happy with my choice for @getumbrel. Same goes for my hardware setup. Not sure how much of an impact my cooling unit exactly has on the Pi but my node is constantly running between 53 and 56 degrees which seems acceptable by all means.
For anyone planning on starting to run a Bitcoin node of their own using Umbrel, regardless if you plan to use a rotary phone as a case, I’d recommend to have a look at the SSD capacity. If you’re not on a tight budget I would suggest to consider a 2TB instead of 1TB. Currently 1TB will do the job just fine, but with the Bitcoin blockchain constantly growing and with Umbrel likely adding more apps to their app store you might find yourself out of space sooner than expected. I’m guessing a 1 TB will last 3 to 4 years or so, while a 2TB gives you a bit more leeway.
Please note that I used a so-called T-65 model rotary phone from the Dutch PTT and other models might have a different interior. That’s not to say all of the above wouldn’t be possible with other models but that would likely require some improvising and creativity.
I’ve got to say that I’m really happy with the result. Happy to have given my 1978 rotary phone a newly found task in the current day and age. Happy with Umbrel and their sleek looking and perfectly working OS. And last but not least, happy to be able to actively contribute to the growth, stability and future of Bitcoin and the Lightning Network.
Don’t Trust, Verify
References
Setup your own personal Bitcoin and Lightning node with the free and open-source platform from Umbrel:
Have a look at this Amazon shopping list for the exact hardware and cables I used:
https://www.amazon.de/hz/wishlist/ls/1P29M1M4BMLHV?ref_=wl_share
You can use the following address to setup a Lightning channel with my node to get you started on the Lightning Network:
02f8aa06386f357da084d66d09c29ced50a5154860eebfd054aeec32b068d6cdf6@mbccp36qrofzbzjqytvasvfzqqtnc2wcca6kmllul7d3x6ebs77ptfqd.onion:9735
