Toddler Phone Calls Family And No One Else

The great thing about the modern world is how connected we are. It’s also the worst thing about the modern world, to be honest. [Allan Binder] wanted to give his toddler the very best of that, and escape the worst, with a specially-designed telephone to call Grandma with– and not get scam calls in turn. We’re not going to say his build guide is so thorough a toddler could follow it, but it’s not too far off.

The device is very simple: a commercial ‘retro-style’ handset pairs with an ESP32-S3 over USB. Said ESP32, aside from acting as a USB host, runs a minimal Session Initiation Protocol (SIP) client, which connects via WiFi to a VoIP account the parent has set up. In this case, [Allan] is using Twilio, but there are other internet telephony providers one could use if a Twilio employee once ran over your dog or something.

There are no inbound calls in this setup, so little Timmy isn’t going  to be bothered needlessly about import fees on nonexistent packages or his car’s extended warranty. Dialing out is toddler-friendly, too– it’s as simple as mashing an arcade button linked to the ESP32’s GPIO. Each designated contact gets a button with its pre-programed contact, like the speed dial of yore. A really nice touch is the use of illuminated buttons tied to the time-zone of the designated contact: kiddo will learn quick that if the button isn’t lit, it’s not time for phone calls. The phone will actually say so, via a text-to-speech that also announces network errors and the like.

While cardboard box housing the prototype seems a bit flimsy to trust with any toddler we’ve met, but the concept here is very sound indeed. We’ve seen such kid-communication devices before, but this implementation, aside from being more current, has a lot to recommend it.

Thanks to [Allan Binder] for the tip!

 

A Hackable Analog Phone System

Do you have old landline phones laying around the house, with touchtone buttons or rotary dials? Perhaps you’d like to do something with them! [Scott Dylewski] has built hardware to let you do just that, since your local utility might have pulled down the lines already.

The Analog Redial is, essentially, a “little phone system you can hack,” according to [Scott]. Plug in a phone or two, and you get the functionality of yesteryear—a dial tone, ringing, and all that. You can make calls between the phones, out via a SIP server, or use the answering machine functionality. You can play around with settings via a web interface, or even set up dial codes so your phone can control your Home Assistant setup.

An ESP32-C6 does all the heavy lifting, with the aid of an ES8388 audio chip, and lets you plug in two phones for telephonic hijinks. You can even add a Bluetooth board to use your old landline as a handset for your modern smartphone. [Scott] has all the files on GitHub if you’d like to make one yourself, and you can get most of it pre-assembled by a board house if that’s your jam. It hardly gets easier than this.

We’ve featured other fun projects that repurpose old phones for new purposes, too. If you’re whipping up telecommunications witchery of your own in the home lab, be sure to notify our tipsline. Happy phonery!

Trying To Get Linux Running On A Nokia E6

The Nokia E6 is a smartphone from back in the old days when Symbian was a thing. [fluffleswaffled] has been doing the work to get the ancient handset running Linux instead, because that’s ultimately cooler than what the phone shipped with out of the box.

There isn’t an unlocked bootloader on the E6, so instead, [fluffleswaffled] used an altogether different route to boot Linux. A Symbian app is used to load the kernel and device tree into RAM, at which point the MMU and caches are turned off and the device jumps into Linux. It’s a one-way trip, from which there is no way back to Symbian without a power cycle. The setup nets a terminal on the phone’s own screen, and the hardware keyboard and touchscreen are functional. The display is controlled by a Broadcom VideoCore III, with [fluffleswaffled] capturing messages from Nokia’s original display driver to create a custom kernel driver that replays them.

There’s an issue, though. The phone doesn’t stay in Linux land for long — it always resets within a couple minutes of booting into the alternative OS. [fluffleswaffled] believes this is because the phone’s baseband chip is supervising the application processor, and killing things once it’s detected that the Symbian mobile stack has stopped running. They’re hoping that someone with experience with Nokia basebands or the relevant hardware can point them in the right direction to get this hack running for more than 3.5 minutes at a time.

There probably isn’t a great deal of utility in getting Linux running on a 2011 smartphone, but we love the hustle nonetheless. We’ve seen this done before, though, and it’s always interesting to learn what it takes to get the OS booting on a new platform. If you’re whipping up similar hacks in your home lab, don’t hesitate to let us know on the tipsline.

Turning A Run-Over Samsung Galaxy S23 Into A Gaming PC

Repurposing old smartphones for more general purpose computing isn’t a new thing, but the project by [LastComputer] ups the ante by going from a Samsung Galaxy S23 that looks like it got run over by at least a few cars to a very serviceable gaming computer, courtesy of its Snapdragon 8 Gen 2 SoC.

The somehow still working but definitely worse for wear phone was purchased for 1,700 Ukrainian Hryvnia (~$40). It being SIM locked also helped reduce the price, even if someone had somehow wanted to use it again as a phone. Since the SoC inside is also used in quite capable gaming handhelds, but with good cooling, that would be a real waste.

Converting it into proper gaming system requires some careful disassembly, some gentle whacking with a hammer to straighten out the frame and a new battery as the mainboard won’t work without one installed.

A 3D-printed phone case glued to an SSD cage for the 512 GB SSD serves as the enclosure, along with two USB hubs, one of which also provides HDMI output. For the active cooling system a heatsink was hot-glued to the vapor chamber with a properly sized fan mounted to it. Here we could definitely see some zip ties being added to prevent it from falling off.

Compared to running the phone in its stock cooling configuration this shaves off about seven degrees C, with thermal throttling noticeably reduced. This consequently provides a much better desktop experience in Samsung’s DeX (Desktop eXperience) desktop mode, which is what’s used for running applications and games.

Running God of War as an emulated PS2 game works pretty well, as does running games with the Dolphin emulator and the GameHub app using which PC games on Steam, GoG and others can be run. Although you can also install other OSes on the phone hardware, Samsung DeX doesn’t appear to be a bad option if you happen to repurpose a high-end Samsung phone that supports this mode.

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A Keyboard With No Keys

For as capable as smartphone hardware is, the software running on them can be especially restrictive and cumbersome. Unlike a single-board computer with GPIO running a standard Linux operating system and some intuitive programming language like Python, smartphones are generally walled gardens where programming major overhead, and if a custom program can be run on them at all the user still has to figure out how to interface hardware with a USB-C port. To skip past all of this, [nicolas.ma] built an audio modem that can send keyboard input to a computer with nothing more than a browser.

The “keyboard” starts off in a browser running on a standard smartphone. A user can input text into the browser, which then gets converted into a series of audible audio pulses that can be sent to the keyboard. The keyboard itself listens to those pulses, decodes them, and then sends the text through to the computer as a standard USB device thanks to an Arduino Micro at the center. Arduino Micros are excellent choices for keyboard controllers because they have a built-in USB chip.

The protocol used here is designed and built by [nicolas.ma] as well. The words allow for variable length, with the device determining message length, and a word-ending scheme that automatically sends the message to memory when it’s detected that the message is finished. There’s also integrity checking and the ability to check on the link’s state. From hardware to software it’s an impressive build, and for anyone wondering what this might be used for [nicolas.ma] has already built a password manager from it.  Continue reading “A Keyboard With No Keys” →

Cell Broadcast: The Modern Emergency Alert System

Once upon a time, telephones were primarily point-to-point communications systems. There were options for three-way and conference calls out there, but by and large the plain old telephone system was about connecting one handset to another for a direct conversation. For this reason, the telephone was seldom used for mass emergency communications, because it was simply not fit for broadcasting a message to a wide number of people.

However, technology has since changed. Our modern phones are all connected to a big digital over-the-air network, and large swathes of them can be addressed all at once if so needed. This has led to the development of emergency warning systems that use the cellular network, with Cell Broadcast being the most notable iteration.

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Phone Stand Aims To Fight Addiction

Sometimes, it’s hard to stop picking up your phone every few minutes to check on notifications and scroll endlessly through the slop of the day. [PushpendraC2] has been working on a solution to this problem that would ideally discourage such behavior —  a nifty little smartphone stand!

The concept is straightforward enough—the smartphone stand uses a simple tactile button to determine if your smartphone is sitting on the little 3D printed shelf, or not. However, the smarts inside do a bit more than that, too. An ESP32-S3 is charged with monitoring whether the smartphone is sitting in place, and starts counting “focus time” while it’s there. If the phone is picked up, the OLED display on the shelf starts ticking down a 5-second timer to encourage you to put it back. If you don’t, the focus time is reset and you lose your streak.

It’s also possible to tap a touch sensor on the device which sets a reminder timer, prompting you to put your phone back after a set period of time, between 2 to 30 minutes. A buzzer will then start going off to prompt you to put the phone down. If you want to track the devices impact, you merely need to log in to the web server hosted by the ESP32, which shows your current focus session time, along with a heatmap of your daily productivity.

It’s a simple idea, but one that uses a few neat psychological hooks to encourage compliance and behavioral change. We’ve featured similar projects in this vein before, No surprise, as phone addiction is a problem experienced by many.

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