Solar Powered Cellphone A True Hack

June 7, 2011 by Mike Szczys 34 Comments

The polished quality of this hack isn’t quite there, but we love the ingenuity and exploration exhibited. [Paulie1982] shows us how to make an old cellphone work with the rays of the sun.

You can see above that he’s added photovoltaic solar cells to the back case of what looks like an old smart phone. He grabbed the cells from two inexpensive solar landscaping lights and inserted them by cutting holes in the case and using black silicone sealant to glue them in place. Each can pump out about 3V and together they get above the 5V threshold that he needs to do some charging. See the build process in the video after the break.

From what we’ve seen there’s zero consideration of current in this hack and that’s what makes us skeptical. Still, we love the idea of trickle charging and we’d love to see some speculation in the comments about how to improve upon this. Surely the additional hardware necessary for proper regulation, etc. could be fit in a custom case cover like the one used for this inductive charger hack.

Continue reading “Solar Powered Cellphone A True Hack” →

GSM-to-Skype Bridge Lets You Lose Those Roaming Fees

May 11, 2011 by Mike Szczys 21 Comments

Here’s the scenario: you’re going to be traveling somewhere and you’ll be charged roaming fees if you use your cellphone. But there is free WiFi available in this place. You can save yourself money by leaving your SIM card at home and using a GSM-to-Skype bridge to take calls on your phone via WiFi.

[Trax] is using a USB GSM modem to take cellphone calls on a PC. He leaves his sim card in this modem so that it can make and receive calls and text messages through your normal telephone number. For some reason, the USB connection only provides control of this modem and doesn’t pass bi-directional audio. To make this happen, he built an audio interface cable using two transformers and a few passive components to connect the modem to the computer’s audio card.

On the software side of things, an application written in Delphi 7 manages the modem, the audio stream, and the Skype application. When a call is incoming it sets up a Skype connection with your handset via the Internet, passing along the caller ID data in the process. If you choose to answer the Skype session the application will pick up the GSM call and you’ll be connected. It works the same way when placing an outgoing call.

This seems easier to manage than a rig that physically pushes a cellphone’s buttons via the Internet.

[Thanks Mure]

Long-range Bluetooth Wardriving Rig

April 15, 2011 by Mike Nathan 56 Comments

bluetooth_wardriving

[Kyle] was digging through a box of junk he had lying around when he came across an old USB Bluetooth dongle. He stopped using it ages ago because he was unsatisfied with the limited range of Bluetooth communications.

He was going to toss it back into the box when an idea struck him – he had always been a fan of WiFi wardriving, why not try doing the same thing with Bluetooth? Obviously the range issue comes into play yet again, so he started searching around for ways to boost his Bluetooth receiver’s range.

He dismantled the dongle and found that the internal antenna was a simple metal strip. He didn’t think there would be any harm in trying to extend the antenna, so he soldered an alligator clip to the wire and connected the CB antenna in his truck. His laptop sprung to life instantly, picking up his phone located about 100 feet away in his house. He took the show on the road and was able to pick up 27 different phones set in discoverable mode while sitting in the parking lot of a fast food chain.

While it does work, we’re pretty sure that the CB antenna isn’t the most ideal extension of the Bluetooth radio. We would love to see what kind of range he would get with a properly tuned antenna.

Keep reading to see a quick demonstration of his improvised long-range Bluetooth antenna.

Continue reading “Long-range Bluetooth Wardriving Rig” →

Quick & Dirty USB Phone Charger

April 14, 2011 by Mike Nathan 33 Comments

usb_phone_charger

Hackaday forum member [Dan Fruzzetti] wrote in to share a simple, yet useful hack he built just the other day. He and his wife both have Evo 4G smartphones and they were pretty disappointed in the lack of portable charging solutions available.

Instead of buying something and modifying it to his needs, [Dan] decided to build a quick and dirty charger instead. His ghetto-mintyboost was built into a cheap project box he found at Radio Shack, which is stocked with a set of four D-cell batteries. The batteries were wired in series and connected to a pair of salvaged USB ports mounted on a small piece of protoboard.

Knowing that most portable devices get 5.7v from their chargers already, he was not worried about hooking his phones straight into the 6v battery pack he built. He says that the phones actually charge pretty quickly, and that he estimates he should be able to get about 50 charges out of the box before he needs to swap the batteries.

This is not a complex hack by any means. It is quick & dirty, solves an annoying problem, and it’s dead simple to build. That’s exactly why we like it.

Real-time GPS Tracker With Mobile Phone Uplink

April 14, 2011 by Noah Dunker 12 Comments

[jayesh] wasn’t actually trying to solve any clever problems when we built his homebrew GPS tracker. He just had the hacker mentality and wanted to build something fun and useful while geeking out with electronics and software.

On the hardware side, he started with an Arduino, then added a GPS module for location detection and a GMS/GPRS module for the data uplink to his server over AT&T’s network. The Arduino uses several libraries and plenty of custom code. On the server, he worked up some wizardry with open-source packages and the Google Maps API. All of the source code and hardware details are well-documented. Put together, it’s a GPS tracker that can update a map in real-time. Sure, there are commercial products that do roughly the same thing, but where’s the fun in that? The principles here can also be put to good use in other microcontroller-based projects.

Are Phones With Haptic Feedback In Our Future?

April 10, 2011 by Mike Szczys 9 Comments

Can we do away with a keypad and just squeeze our phones to check messages and dial contacts? [Sidhant Gupta] has been researching the idea of an electronically adjustable spring mechanism that might just make this possible. He calls the prototype above the SqueezeBlock. If you pick it up and give it a squeeze you can feel springs pushing back against your fingers, but it’s all a trick. Inside you’ll find one motor with a gear that converts the linear motion into a rotating force. Attached to the same axle as that gear are a motor and a rotary encoder. A microcontroller monitors that encoder to detect a user squeezing the two plates together, then drives the motor to vary the resistance. [Sidhant] outlines some possible uses that included stiffer resistence as unread email starts to pile up, or squeezing the device to its smallest size to turn the ringer volume all the way down.

We’re a little skeptical of this functionality in handhelds just because of the power consumption issue. But if that is somehow overcome we think this would make a pretty interesting phone feature… at least at first. Click through the link above for a video demonstration or get the details from the research presentation (PDF)

[Thanks Dan]

A Breakout Board For Your Android Phone

April 7, 2011 by Brian Benchoff 50 Comments

[sparkfun] announced a new board called the IOIO (pronounced “yo-yo”) this week that allows communication from your Android devices to your upcoming projects.

The board hasn’t been released yet; [sparkfun] is still pulling together documentation and waiting on their first production run. We do know that the board contains a PIC24F MCU, and will give your phone analog input, and Digital I/O, PWM, I2C, SPI, and UART control. Communication with the board is over the USB port on your phone.

The brilliant thing about this board is that an external programmer isn’t required. Everything you connect to this board can be controlled from within Android apps. We covered Android development in a hackaday tutorial series before, so now it’s possible to put these skills to give your projects a touch screen, internet and bluetooth connections, a camera, or your phone’s accelerometers. Very slick.

Video of some basic functions demonstrating what possible with this board after the jump, but feel free to comment and tell us what you’d like to see done with this board.