Motion Activated Cell Phone Tracker

HOVER OVER THE PHOTOS WITH YOUR MOUSE FOR TIPS AND ADDITIONAL DIRECTIONS. !!

This is the tutorial on how to build the switch I developed, to turn a cell phone used for GPS tracking, on and off with motion. This switch will alleviate the problem of J2ME java applications from locking up during long run times (over days or weeks).

Soldering is required. Sparkfun has a great Soldering Tutorial if you need help.

The next step will walk you through what I do when I make them and the order that I have found works best, as well as a couple of tips to make it easier.

Good luck and more importantly, have fun!

This shows the 28 Pin DIP socket, which will hold the AVR chip in place, in the board. Notice that there is a small semi-circle cutout at one of the long ends of the socket. This should match up with the picture on the circuit board.

In this photo, you will see the 14 pin DIP socket in place. This holds the 4066 switching chip. Put this is and solder it in place. PAY ATTENTION TO THE DIRECTION. IT HAS A SMALL SEMI CIRCLE ON THE END CLOSEST TO THE 28 PIN SOCKET. THIS SHOULD MATCH THE PICTURE ON THE BOARD.

Add the six pin female socket. Put it in the JP1 spot. I sometimes use a little duct tape to hold it in place, so that when I turn it over to solder it, it doesn't fall out.

Now add the three resistors. Look at the one to the right of the board in the first photo and see how it is bent. Bend all three like this. Put them in the spots labeled R1, R2 and R3. These do not have a direction. Solder them in place and AFTER you do that, cut the loose ends off from the underside of the board.

Now it's time to add the 3 power connectors. Put them in like the photo shows. These must be put in the correct way or you will BURN OUT THE PHONE. I use duct tape to hold them in place so that they don't fall out when I turn over the board and solder them in. See the photos.

Solder the 6 pin male connectors to the accelerometer. The short side of the pins should come out the top of the accelerometer and the long ends are on the bottom. Solder on the top side. See the photo.

Now it's time to put the microchips in their sockets. Each of the microchips has the same small semicircle on one end that I discussed earlier. Make sure this lines up with the semi circle in the sockets. Oh yeah.....put the 14 pin chip in the 14 pin socket and the 28 pin chip in the 28 pin socket. You might have to slightly bend the pins inwards to get them to go into the sockets. A lot of times, they come sort of "bow legged". I usually just put the chip in its side, on a table and GENTLY roll it until the pins are straight. I do this for both sides.

Here is the finished board with the chips in.

DO NOT SOLDER TO THE BATTERY !!!!!!! YOU ARE SOLDERING TO THE PHONE !!!!!!!

YOU WILL NOT BE ABLE TO USE YOUR ORIGINAL BATTERY AFTER THIS STEP. YOU WILL HAVE TO USE AN EXTERNAL 3.7 volt BATTERY

Now it's time to solder the wires to your phone. I am using the iDEN 425. This step should be generic for just about any phone. Basically you are soldering a red wire where the positive terminal of the battery touches the phone and a black wire to the spot where the negative terminal of the battery connects to the phone. The 425 phone has four metal tabs that touch the battery. the two outside tabs are the power tabs. You can look at your battery and they usually have a + on the spot for positive and a - on the spot for the negative. I don't know what the other two tabs are used for.


After you solder wires to the battery power terminals of the PHONE AND NOT THE BATTERY, you will be solder wires to the ON / OFF button of the phone. You will have to take off the cover and pull back the front pads. Its stuck on with glue. Just do it gently. I use duct tape again to hold the pad back.

Find the circular pad for the ON / OFF button. On the 425, the center of the circle is the positive and the outside edge is negative. So......solder the red wire to the center dot and the black wire to the outside ring.

Now you can put the phone back together and route the wires however you like so that you can get to them

Now look at the ends of the wires that you just soldered to the phone. In particular, look at the loose ends. Solder the exposed ends of the red and black wires to the metal tabs for the JST power connectors. See the photos.

After you do this, push the metal tabs into the female power connectors. There is a groove on the back of the female connector. This groove mates with the tall back on the male counter parts that you already soldered to the board. Face the groove away from you and make sure the red wire gets pushed into the right side and the black wire goes to the left side. IF YOU MESS THIS PART UP, YOU'LL BURN EVERYTHING UP.

Look at that photo and the notes on the photo to see where to plug the wires in.

Plug the wires from the battery (your external 3.7 volt), the on / off button of the phone and the + and - terminals of the back of the phone, into the circuit board that you put together. Plug the battery in last. As soon as you do this, (15 seconds or so) the phone should turn on. Your ready to go!!