Phone Hacks

215 Articles

pi 1990s brick phone

No More Paperweight: This Vintage Brick Phone Is Back Online

March 13, 2026 by 20 Comments

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.

Continue reading “No More Paperweight: This Vintage Brick Phone Is Back Online” →

Are We Finally At The Point Where Phones Can Replace Computers?

March 11, 2026 by 106 Comments

There was an ideal of convergence, a long time ago, when one device would be all you need, digitally speaking. [ETA Prime] on YouTube seems to think we’ve reached that point, and his recent video about the Samsung S26 Ultra makes a good case for it. Part of that is software: Samsung’s DeX is a huge enabler for this use case. Part of that his hardware: the S26 Ultra, as the upcoming latest-and-greatest flagship phone, has absurd stats and a price tag to match.

First, it’s got 12 GB of that unobtanium once called “RAM”. It’s got an 8-core ARM processor in its Snapdragon Elite SOC, with the two performance cores clocked at 4.74 GHz — which isn’t a world record, but it’s pretty snappy. The other six cores aren’t just doddling along at 3.62 GHz. Except for the very youngest of our readers, you probably remember a time when the world’s greatest supercomputers had as much computing power as this phone.

Continue reading “Are We Finally At The Point Where Phones Can Replace Computers?” →

Old Desk Phone Gets DOOM Port

March 3, 2026 by 2 Comments

Old desk phones are fairly useless these days unless you’re building a corporate PBX in your house. However, they can be fun to hack on, as [0x19] demonstrates by porting DOOM to a Snom 360 office phone. 

The Snom 360 is a device from the early VoIP era, with [ox19] laying their hands on some examples from 2005. The initial plan was just to do some telephony with Asterisk, but [ox19] soon realized more was possible. Digging into a firmware image revealed the device ran a Linux kernel on a MIPS chip, so the way forward became obvious.

They set about hacking the phone to run DOOM on its ancient single-color LCD. Doing so was no mean feat. It required compilation of custom firmware, pulling over a better version of BusyBox, and reworking doomgeneric to run on this oddball platform. It also required figuring out how the keyboard was read and the screen was driven to write custom drivers—not at all trivial things on a bespoke phone platform. With all that done, though, [0x19] had a dodgy version of DOOM running slowly on a desk phone on a barely-legible LCD display.

Porting DOOM is generally a task done more for the technical thrill than to actually play the game on terribly limited hardware. We love seeing it done, whether the game is ported to a LEGO brick or a pair of earbuds. If you’re doing your own silly port, don’t hesitate to notify the tipsline—just make sure it’s one we haven’t seen before.

A Working Intercom From Antique Telephones

February 9, 2026 by 13 Comments

Although it can be hard to imagine in today’s semiconductor-powered, digital world, there was electrical technology around before the widespread adoption of the transistor in the latter half of the 1900s that could do more than provide lighting. People figured out clever ways to send information around analog systems, whether that was a telegraph or a telephone. These systems are almost completely obsolete these days thanks to digital technology, leaving a large number of rotary phones and other communications systems relegated to the dustbin of history. [Attoparsec] brought a few of these old machines back to life anyway, setting up a local intercom system with technology faithful to this pre-digital era.

These phones date well before the rotary phone that some of us may be familiar with, to a time where landline phones had batteries installed in them to provide current to the analog voice circuit. A transformer isolated the DC out of the line and amplified the voice signal. A generator was included in parallel which, when operated by hand, could ring the other phones on the line. The challenge to this build was keeping everything period-appropriate, with a few compromises made for the batteries which are D-cell batteries with a recreation case. [Attoparsec] even found cloth wiring meant for guitars to keep the insides looking like they’re still 100 years old. Beyond that, a few plastic parts needed to be fabricated to make sure the circuit was working properly, but for a relatively simple machine the repairs were relatively straightforward.

The other key to getting an intercom set up in a house is exterior to the phones themselves. There needs to be some sort of wiring connecting the phones, and [Attoparsec] had a number of existing phone wiring options already available in his house. He only needed to run a few extra wires to get the phones located in his preferred spots. After everything is hooked up, the phones work just as they would have when they were new, although their actual utility is limited by the availability of things like smartphones. But, if you have enough of these antiques, you can always build your own analog phone network from the ground up to support them all.

Continue reading “A Working Intercom From Antique Telephones” →

Limiting Battery Risk On Repurposed Smartphones With PostmarketOS

February 1, 2026 by 28 Comments

PostmarketOS is a Linux distribution specifically designed for those who wish to repurpose old smartphones as general-use computers, to a degree. This can be a great way to reuse old hardware. However, for [Bry50], it was somewhat discomforting leaving the phone’s aging lithium battery perpetually on charge. A bit of code was thus whipped up to provide a greater measure of safety.

The concept is simple enough—lithium batteries are at lower risk of surprise combustion events if they’re held at a lower state of charge. To this end, [Bry50] modified the device tree in PostmarketOS to change the maximum charge level. Apparently, maximum charge was set at a lofty 4.4V (100%), but this was reconfigured to a lower level of 3.8V, corresponding to a roughly 40-50% state of charge. The idea is that this is a much healthier way to maintain a battery hooked up to power for long periods of time. There’s one small hitch—the system will get confused if the battery voltage is higher than the 3.8 V setpoint when switching over. It’s thus important to let the device discharge to a lower level if you choose to make this change.

It’s a neat mod that both increases safety, but keeps the battery on hand to let the system ride through minor power outages. If you’re new to the world of repurposing old smartphones, fear not. [Bryan] also has a tutorial on getting started with PostmarketOS for the unfamiliar. If you’re working on your own projects in this space, we’d love to hear about them—so get on over to the tipsline!

Create A Tiny Telephone Exchange With An Analog Telephone Adapter

January 26, 2026 by 15 Comments

An analog telephone adapter (ATA), or FXS gateway, is a device that allows traditional analog phones to be connected to a digital voice-over-IP (VoIP) network. In addition to this, you can even create a local phone exchange using just analog phones without connecting to a network as [Playful Technology] demonstrates in a recent video.

The ATA used in the video is the Grandstream HT802, which features one 10/100 Mbps Ethernet port and two RJ11 FXS ports for two POTS phones, allowing for two phones to be directly connected and configured using their own profiles.

By using a multi-FXS port ATA in this manner, you essentially can set up your own mini telephone exchange, with a long run of Cat-3 possible between an individual phone and the ATA. Use of the Ethernet port is necessary just once to configure the ATA, as demonstrated in the video. The IP address of the ATA is amusingly obtained by dialing *** on a connected phone and picking 02 as menu option after which a synthetic voice reads out the number. This IP address gets you into the administration interface.

Continue reading “Create A Tiny Telephone Exchange With An Analog Telephone Adapter” →

The Nokia N900 Updated For 2025

December 23, 2025 by 15 Comments

Can a long-obsolete Linux phone from 2009 be of use in 2025? [Yaky] has a Nokia N900, and is giving it a go.

Back in the 2000s, Nokia owned the mobile phone space. They had a smartphone OS, even if they didn’t understand app distribution, they had the best cameras, screens, antennas, the lot. They threw it all away with inept management that made late-stage Commodore look competent. Apple and Android came along, and now a Nokia is a rarity. Out of this mess came one good thing, though: the N900 was a Linux-based smartphone that became the go-to hacker mobile for a few years.

First up with this N900 is the long-dead battery. He makes a fake battery with a set of supercapacitors and resistors to simulate the temperature sensor, and is then able to power it from an external PSU. This is refined to a better fake battery using the connector from the original. The device also receives a USB-C port, though due to space constraints, not the PD identifiers, making it (almost) modern.

Because it was a popular hacker device, it’s possible to upgrade the software on an N900. He’s given it U-Boot, and now it boots Linux from an SD card and functions as an online radio device.

That’s impressive hackability and longevity for a phone, if only we could have more like it.