The 2G Raspberry Pi Smartphone

For [Tyler]’s entry to the Hackaday Prize, he’s making something that just a few years ago would be unheard of in a homebrew build. He’s making a DIY smartphone. Yes, with cheap single-board Linux computers, GSM modules, and SPI touchscreen displays, it’s possible to build your own smartphone.

Inside [Tyler]’s DIY smartphone is a Raspberry Pi Model A, a 3.5 inch touchscreen PiTFT with 480×320 resolution, and an Adafruit FONA module The connections are simple enough; the TFT is connected over SPI, and the GSM module over serial. The entire device is powered by a 1200mAh LiIon battery, charged with a powerboost board, runs an operating system written in Python capable of making calls, sending texts, and takes pictures with a Pi camera.

This is not what you would normally call a smartphone. The FONA module is 2G only, meaning you’re limited to 2G speeds and 2G networks. AT&T will be shutting down 2G networks in a little bit, although T-Mobile will be keeping them up for anyone who still has an old Nokia Brick.

That said, [Tyler]’s phone is still exactly what you want in a minimal phone: it just makes calls and receives texts, it has a camera, and unlike the Nokia, you can take it apart and repair it easily. Not that you ever had to do that with a Nokia…

Hackaday Links: January 11, 2015

Listening tests reveal significant sound quality differences between various digital music storage technologies. Finally the audiophile press is tackling the important questions. This listening test looks at the difference between two four-bay NAS boxes, with one making the piano on Scherzo and Trio from Penguin Café Orchestra’s Union Cafe sound more Steinway-like, while another NAS makes it sound more like a Bosendörfer. Yes, your choice of digital storage medium can change the timbre of a piano. Another gem: “Additionally, the two units also had different processor architectures, which might also affect perceived audible differences.” There must be a corollary to Poe’s Law when it comes to audiophiles…

[10p6] has begun a project that can play every old Atari cartridge. Right now it’s just a few bits of plastic that fits every non-Jaguar Atari cartridge, but it’s a start.

The Android IMSI-Catcher Detector. You’ve heard about Stingrays, devices used by law enforcement that are basically fake cell towers. These Stingrays downgrade or disable the encryption present in all cellphones, allowing anyone, with or without a warrant, to listen in on any cell phone conversation. Now there’s an effort to detect these Stingrays. It’s open source, and they’re looking for volunteers.

[Rob] sent in something that’s the perfect application of projection mapping. It’s called Face Hacking, and it’s pretty much just a motion capture systems, a few projectors, a whole lot of CG work, and just a tiny bit of dubstep. It look cool, but we’re wondering what the applications would be. Theatre or some sort of performance art is the best I can come up with.

A while ago, [4ndreas] saw a 3D printed industrial robot arm. He contacted the guy for the files, but nothing came of that. [4ndreas] did what anyone should do – made his own 3D printable industrial robot arm. The main motors are NEMA 17, and printing this will take a long time. Still, it looks really, really cool.

Call A Cell Phone, Find A Tent

relay Finding your tent at a music festival is a tricky endeavor – not only are there miles and miles of tents exactly like yours, you most likely have a few beers or other substances in you that affect your sense of space and/or time.  [James] came up with a great solution to finding your tent by illuminating it with Christmas lights and a cell phone.

The basic idea of [James]’ build is having Christmas light flicker whenever he calls a phone. One feature in nearly every phone that can be exploited to accomplish this task is the backlight turning on when a call is received. Add a phototransistor, a little bit of circuitry, and some Christmas lights, and you have a fully functioning tent finder.

[James]’ circuit is a simple relay driving the Christmas lights, triggered by a phone right on top of the phototransistor. It’s a simple circuit that can be built on a piece of veroboard, and with a few pieces of plastic forming the enclosure, provides a reasonably bulletproof device that will survive the rigors of a music festival. As a bonus, there’s no need to modify the phone to trigger a remote circuit. Video of the device in action below.

Continue reading “Call A Cell Phone, Find A Tent”

Phoenard: Arduino Phone as Small as An Arduino Mega

 

Hanging out at one side of the Atmel booth at Maker Faire was [Pamungkas Sumasta] who was showing off his Arduino cellphone called Phoenard. We really like the form-factor but its hackability is where it really shines. [Sumasta] showed off the menu system which is quite snappy and makes it simple for you to add your own applications. Software isn’t the only thing you can customize, as there’s a connector at the bottom of the phone. He showed off a breadboard attachment which was hosting LEDs of various colors. Their intensity can be altered using a simple slider app on the touchscreen. But there’s more power if want it. Also on exhibit was a self-balancing robot body which has a connector at the top for the phone.

[Sumasta] won the Atmel Hero contest and we assume that’s how he made it all the way to San Francisco from The Netherlands for Maker Faire. You can learn a few more technical details about Phoenard on the Facebook page.

Magsafe On An Android, Cats And Dogs Living Together

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We’re thinking most Hackaday readers have at one time or another been tasked with replacing the power connector in a laptop. Anyone who has done so can easily see the genius behind the Apple Magsafe connector. Since the second gen iPhone, there have been rumors Apple will release a cellphone with the Magsafe connector, a great idea, seeing as how cell phones are thrown around even more than laptops. [Tony] got tired of waiting, and had an Android device anyway, so he decided to retrofit a Magsafe power adapter to his Note II.

In the interest of excess, [Tony] is using the absurdly large ZeroLemon 9300mAh battery and case for his device, giving him a lot of room for this hardware mod. A tiny 3D printed adapter fits around a slightly modified Magsafe connector, and with a little bit of super glue and solder, the connector is wired up to the charging port.

Of course the charger isn’t a stock Apple power supply; it’s just another Magsafe plug wired into a 5V wall wart. We’re not going to take a guess at what would happen if [Tony] plugged a stock Apple charger into his modded phone, but the mod works perfectly without the danger of ripping a USB port out of his phone.

Arduino cellphone

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The fact that you can build a cellphone around an Arduino is pretty neat. But we’re drawn to this project more as a testament to the advancement of hobby electronics. An [Average Joe] can build this thing with a minimum or background knowledge and without breaking the bank. Wow.

Of course this isn’t the first DIY cellphone we’ve come across. One of our favorites is this one which resides on a home etched PCB. There was even another Arduino offering with similar components back in September. But the one seen above really pulls it all together into a package that is usable for everyday life. The components include and Arduino Uno, GPRS shield from Seeed Studios, a TFT touch screen, Lithium battery and charging circuit, and a few other bobbles. All of it is mounted inside of a 3D printed case.

A simple phone calls for a simple UI and that’s included as well. The main menu has two buttons, one for placing a call, the other for sending a text. From there you get the virtual keypad seen above for typing out the phone number or composing a message.

[Thanks Victorzie]

Critter cam hacked from an old cellphone.

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[Art Barrios] kept having night-time visitors who were raiding his dog’s food storage bin. It’s a plastic tub with a lid that latches but the critters were knocking it over and popping that lid off. He wanted to find out which animal was the culprit so he hacked together an automatic camera system using an old cellphone.

You can see the majority of the hardware he used in the image above. There’s an Arduino on the left. This monitors a switch which he added to the lid of the food storage container. It triggers the system when opened, switching on an LED light and snapping pictures.

The touchscreen button is used to trigger the shutter. That’s what all of that tin foil is about. Some experiments led [Art] to realize that a metal ‘finger’ could register on the screen if there was enough foil attached. To move the metal bracket he uses a solenoid. The last problem he faced was keeping the cellphone screen awake. He figured out that power cycling the charger does the trick. The Arduino manages this using a mains-rated relay.

The system successfully captured images of a family of raccoons feasting on the tasty morsels.