The 80s Called: They Say This DIY Phone Is, Like, Totally Rad

Like more than a few of us , [Kevin Noki] is sick of being pulled out of flow state by that annoyingly addictive black rectangle we all carry around. His solution was to build a phone to escape his phone, in a YouTube video we embedded down below. We’d say that phone is straight out of the 1980s, except it’s not quite a phone. It would perhaps be more accurate to say he’s building a Bluetooth handset– actual telephony remains the province of a professional device with regulatory approval, because getting custom hardware on VoLTE is a nonstarter in many places.

He starts out using an ESP32, because he already had one and why not? It’s got bluetooth, after all. Alas, audio quality he was getting through it was a little too crunchy, so he pivoted to use a dedicated Hands Free Profile (HFP) bluetooth module that is purpose built for exactly this kind of application. He’s selling the design on his website, but given how much detail he shows on screen, recreating your own version would be easy enough to save the quid. You’d be missing out on the STL for the fantastic 80s brick he’s made, which may be the most interesting part of the build to us.

We’d likely have jumped right to CAD and printed out a few iterations of the case until we were happy, but [Kevin] takes a more traditional industrial-design approach, mocking up the phone with XPS foam and a manually-operated hot wire cutter. It’s not a step we see makers take very often, but it pays off here– at least for subtracting material, it’s a very quick way to iterate, and he only needs to do one 3D print for the final version. We also like very high-tech acrylic bending jig, which he uses to put some black LED acrylic over the display.

It’s a lot of work to make you less-likely to grab a phone you still need anyway– remember, there’s no cellular modem in this– but, hey, it beats torturing yourself, or worse, a tamagotchi.

pi 1990s brick phone

No More Paperweight: This Vintage Brick Phone Is Back Online

Remember those brick cellphones in the 1990s? They were comically large by today’s standards. These phones used the 1G network to communicate and, as such, have been unusable for decades now. However [Alan Boris] has resurrected this classic phone to operate today.

Originally costing as much as today’s top-of-the-line phones, but instead of weighing just a few ounces this classic Motorola DynaTAC 8000 Classic 2 tips the scales at a hefty 1.5 lbs. [Alan Boris] decided to not just bring the electronics back to life, but to even stuff a modern cellphone inside it to make it fully functional. Given the size of this phone, finding room for the new innards wasn’t much of a challenge. In fact, after the retrofit there was less in the phone than when it started life.

Using a perfboard and some tactile switches he was able to sense the button presses on the phone’s keypad and relay those to a Raspberry Pi Pico 2. The Pico in turn drove a small color LCD to replicate the original screen and controlled a pair of ADG729 boards used to dial the BM10 cellphone within this cellphone. The BM10 is a cellphone about the size of a 9V battery, making it easy to put inside the DynaTAC and bring the handset back to the modern cellular network.

Thanks [Alan Boris] for the tip! Be sure to check out our other cellphone hacks as well as some of our other retrofit hacks.

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Shmoocon 2017: Dig Out Your Old Brick Phone

The 90s were a wonderful time for portable communications devices. Cell phones had mass, real buttons, and thick batteries – everything you want in next year’s flagship phone. Unfortunately, Zach Morris’ phone hasn’t been able to find a tower for the last decade, but that doesn’t mean these phones are dead. This weekend at Shmoocon, [Brandon Creighton] brought these phones back to life. The Motorola DynaTAC lives again.

[Brandon] has a history of building ad-hoc cell phone networks. A few years ago, he was part of Ninja Tel, the group that set up their own cell phone network at DEF CON. That was a GSM network, and brickphones are so much cooler, so for the last few months he’s set his sights on building out a 1G network. All the code is up on GitHub, and the hardware requirements for building a 1G tower are pretty light; you can roll your own 1G network for about $400.

The first step in building a 1G network, properly referred to as an AMPS network, is simply reading the documentation. The entire spec is only 136 pages, it’s simple enough for a single person to wrap their head around, and the concept of a ‘call’ really doesn’t exist. AMPS looks more like a trunking system, and the voice channels are just FM. All of this info was translated into GNU Radio blocks, and [Brandon] could place a call to an old Motorola flip phone.

As far as hardware is concerned, AMPS is pretty lightweight when compared to the capabilities of modern SDR hardware. The live demo setup used an Ettus Research USRP N210, but this is overkill. These phones operate around 824-849 MHz with minimal bandwidth, so a base station could easily be assembled from a single HackRF and an RTL-SDR dongle.

Yes, the phones are old, but there is one great bonus concerning AMPS. Nobody is really using these frequencies anymore in the US. That’s not to say building your own unlicensed 1G tower in the US is legally permissible, but if nobody reports you, you can probably get away with it.

Bringing The Zach Morris Phone Into The 21st Century

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With the gravitas of [Michael Douglas] in Wall Street and the technological amazement of [Zach Morris] on Saved By The Bell, the classic 1980s ‘brick’ cell phone has a lot to offer these days. Not only is it large enough to be used as a blunt weapon, it’s also useful as an anchor and more durable than an old-school Nokia. Most, if not all of these phones have gone silent since analog cellular service went dead a few years ago, but that didn’t stop [Andrew] from bringing his back to life.

The core of this build is a 128×64 OLED screen that replaced the old seven-digit, seven-segment display and a very small GSM module. The ancient PCB was discarded and a new hardware revision was created in Eagle based on an Arduino-powered microcontroller. The buttons from the original phone remained, thanks to a custom designed resistive button footprint on the PCB and a bit of conductive ink.

What’s surprising is this phone actually works. [Andrew] can not only receive texts on his phone, but also send them using his own implementation of a number pad keyboard. It’s an awesome build, and from what we can tell, the first proper DIY cell phone we’ve ever seen. About time someone got around to that, and we couldn’t have hoped for a better form factor.