November 15, 2005 12:09 PM PST
Build-it-yourself cell phones
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Most aren't starting entirely from scratch. To comply with regulatory requirements, the projects have to find radio components that have already been approved by the FCC.
In this vein, tinkerers have found several companies that sell components originally meant for embedded systems such as surveillance cameras or GPS (Global Positioning System) receivers, which are allowed to transmit on the big cell phone networks.
Small screens and keypads are relatively easy to come by. The recent emergence of tiny Linux-based computer systems, each about the size of a pack of gum, have given them the brains for the phones. Cheaper "microcontrollers" are also available, which are simpler to install, but provide far less flexibility for applications.
Once all of those parts are connected, a homebrew phone needs a Subscriber Identification Module, or SIM, card, the little chip that stores information about which carrier network to use, what the phone's number is, and other personal data. These can be taken out of any GSM (Global System for Mobile Communications)-based phone, or can be purchased on a prepaid basis.
Cingular Wireless and T-Mobile phones both use the GSM wireless standard in the United States. Other carriers use a different technology, which makes it harder for the tinkerers to adapt their equipment.
The early phone tinkerers are hoping that their work sparks a broader response in the open-source community. Once a few people show a way forward in hardware, interesting things can be done by other software developers, they say.
Patel is helping organize an Emerging Telephony Conference with tech publisher O'Reilly Media in January, where he hopes to show off as many grassroots development projects as he can find.
"I have very selfish goals," Patel said. "I want to create demos and prototypes to show clients, and I can't demonstrate the future to you if I can't actually access it. But it's very clear that it's the hacker kids that are doing all the cool stuff."
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