DIY Cellphone

download DIY Cellphone

of 20

  • date post

  • Category


  • view

  • download


Embed Size (px)

Transcript of DIY Cellphone

  • 8/13/2019 DIY Cellphone


    DIY CellphoneThe DIY Cellphone is a working (albeit basic) cellphone that you can make yourself. It can make and receive

    phone calls and text messages, store names and phone numbers, and display the time. It builds on the hardware

    and software in theArduino GSM Shieldbut extends it with a full interface, including display, buttons, speaker,

    microphone, etc. The source files for the cellphone are hosted on GitHub (hardware,software), which also

    includes an issue list where you can file bug reports or request enhancements.

    V A R I A T I O N S

    There are two main variants of the DIY cellphone: one that uses a black and white LCD like those found on old

    Nokia phones and one that uses an eight-character matrix of red LEDs. The LCD shows more information (six

    lines of fourteen characters) but breaks over time. The variant with the LED matrix is harder to use but the display

    is more robust.

    M A K I N G T H E P H O N E

    Making the DIY cellphone can be a fairly involved process but it doesn't necessarily require specific electronics

    expertise. You'll need to order the circuit board and electronics components (about $200 total) and have access

    to some other electronics tools. There's a good amount of fine hand soldering to be done: about 60 components,

    mostly surface-mount, which can take from one to five or ten hours, depending on your experience. Programming

    and, especially, debugging the phone can take a while again, depending on your experience and how much

    goes wrong. Making the case requires some plywood and veneer, along with access to a laser cutter (or you can

    find your own way to enclosure the circuit board). In short, this is a difficult but potentially do-able project.

    O R D E R I N G T H E C I R C U I T B O A R D

    You can order a version of the circuit board fromOSH Park.It costs about $60 and you get three copies of the


    OrderLCD variantfrom OSH Park. OrderLED matrix variantfrom OSH Park.Alternatively, you can upload the Gerber files to a fabrication service yourself, eitherOSH Park,Advanced

    Circuits,AP Circuits,or a number of others. Each time I order boards, I save the Gerber files in my GitHub

    repository, in a directory named according to the date. Find the latest here:LCD variant,LED matrix variant.

    There are a few different files in the directory:

    .cmp: top (component) side copper layer (i.e. the lines of copper forming the actual electronic connections onthe top side of the board)

    .sol: bottom (solder) side copper layer (same, for the bottom of the board) .stc: top (component-side) solder mask (stop) layer (i.e. the green layer covering the copper) .sts: bottom (solder-side) solder mask (stop) layer .plc: top (component-side) silk screen (legend) layer, plus overall board dimensions (i.e. the white text on the

    top of the board, plus a line indicating the overall board shape for which there isn't a separate file)

    .pls: bottom (solder-side) silk screen (legend) layer (white text on the bottom of the board) .drd: (excellon) drill file (specifies where holes should be drilled in the board and how big they should be) .dri: drill tool file, often not needed (text description of the drill sizes used)You'll need to upload these (typically in a single zip file) and sometimes specify which file is what. This is a two-

    layer board, 5.15" x 2.3", and the standard options for board thickness (0.62"), copper weight (1 oz), and solder

    mask should be fine. You'll want to get solder mask and silk-screen on both sides. Getting the corners rounded

    might count as a complex shape and cost extra; I think it's worth it but it's not necessary.

    G E T T I N G T H E P A R T S

    There's no kit available for the cellphone but you can order the parts from various websites.
  • 8/13/2019 DIY Cellphone


    Electronic Components

    Most of the electronic components are available fromSparkFunandDigi-Key.You'll also need to get theM10

    GSM Modulefrom the Arduino store.

    Bill of Materials:BOM.pdf(LCD variant),BOM.pdf(LED matrix variant)


    To assemble the phone, you'll a need a good soldering setup: a soldering iron (e.g. the WES51)with a good tip,fine-pitch solder, desolder wick, tweezers, etc. To program the microcontroller, you'll need an AVR in-system

    programmer (like theAVRISP mkII)and a3.3V FTDI Cable(or equivalent breakout board). To charge the battery,

    you'll need a mini-USB cable.

    To make the laser-cut case, you'll need access to a laser cutter and a small philips screwdriver.

    SIM Card

    The phone should work with a full-size SIM card from any GSM provider. I've been using T-Mobile in the United

    States but the phone has also been tested with AT&T and in India, China, and Europe.

    Other Materials

    For the laser cut enclosure, you'll need:

    A sheet of 1/4" / 6 mm plywood, like thiscraft plywood from Midwest Productsavailable at many art supplystores. (Avoid the micro-lite aircraft plywood from Midwest Products or other plywood with dark adhesive

    layers as they tend to burn in the laser-cutter.)

    A sheet of wood veneer, preferably with adhesive backing. Six M0, 5/8", pan-head machine screws (e.g. this100 pack from McMaster-Carr) Six M0 nuts (e.g. this50 pack from McMaster-Carr)Or, try making a difference enclosure (e.g. with 3D-printing or by milling a mold).

    Images of the assembled circuit boards (LCD variant). Click to enlarge.

    Images of the assembled circuit boards (LED matrix variant). Click to enlarge.

    S O L D E R I N G T H E E L E C T R O N I C S