Kris Kumar
10-04-2004, 08:40 PM
Motorola MPx200 is an awesome Smartphone. Motorola engineers put out an <i>almost perfect</i> Smartphone 2002 based device. I am calling it <i>almost perfect</i> because it has one critical shortcoming. The signal reception is nowhere near perfect. The device has served me well and in spite of the fact that Motorola never released the Windows Mobile 2003 for this device, I have been very happy with its features and the way they have been implemented. Except for the signal quality; inside my office building and at home, I get only one bar or at times none. :-( Past experience has taught me that the Antenna Booster stickers <i>"do not"</i> work. So I set out to design my own antenna booster. I am mighty pleased with the results of the half-hour operation that I carried out on my phone. The phone looks a little odd with the 3" wire sticking out of it, but it works! :-)<br /><br /> <img src="http://www.smartphonethoughts.com/images/Collage1Small.jpg" alt="User submitted image" title="User submitted image"/> <br /><br /><b>Note:</b> I must warn the <i>Do-It-Self'ers</i> that I <i>cannot guarantee</i> that this will work for you. Not to forget, you will be voiding the warranty on the Smartphone. I am posting this article <i>not</i> as a How-To guide, but as an article that proves that the signal reception on the MPx200 could have been improved had the Motorola engineers not cared about the aesthetics and built an external antenna into the phone.<br /> <!> <br />I have had this experiment in my mind ever since I got the phone, but never had enough confidence to carry it out. Now that MPx220 and other Smartphones are close to their launch date. I thought that even if I goof up, this will give me an excuse to buy a new Smartphone right away. And if it worked I would be able to wait a month or two, for the prices on the new Smartphones to settle down. It was a win-win situation. ;-)<br /> <br />So you want me to end the <i>blah-blah</i> and get down to the details of how I actually did it. <br /><br /><img src="http://www.smartphonethoughts.com/images/Internal-AntMarked2.JPG" alt="User submitted image" title="User submitted image"/> <br />Figure 1: Once you remove the four screws under the battery cover and release the two clips on the side, this is what you will see. I have marked the original antenna. <br /><br />The antenna is a small metal plate. No wonder the reception is not that great. Of course the circuitry can also be blamed for not boosting the signal enough. But I am convinced that the small metal plate is the reason for poor reception and decide to proceed with my experiment.<br /><br /><img src="http://www.smartphonethoughts.com/images/IMG_2477 BackCoverHow1Small.jpg" alt="User submitted image" title="User submitted image"/> <br /><i>Figure 2: I then drilled a hole into the back of the cover and passed a wire through the hole. I wish I had done a little more research on how antennas work and picked up a wire of suitable gauge. But I had some wire sitting in my hobby kit box and didn't want to go wire shopping (read that as lazy).</i><br /><br /><img src="http://www.smartphonethoughts.com/images/ConnectionSmall.jpg" alt="User submitted image" title="User submitted image"/><br /><i>Figure 3: I soldered the wire to the antenna connector.</i><br /><br /><img src="http://www.smartphonethoughts.com/images/IMG_2478 BackCoverSmall.jpg" alt="User submitted image" title="User submitted image"/> <br /><i>Figure 4: Another picture of the back cover showing the hole and the wire passing through it. I chose to drill the hole in the back because I was worried that I may crack the plastic if I drill the hole on the top (where the antenna is located usually).</i><br /> <PAGEBREAK> <br /><span><b>Time To Pack Up</b> </span><br /><br /> <img src="http://www.smartphonethoughts.com/images/MPx200 AB04_RJ Back2Small.jpg" alt="User submitted image" title="User submitted image"/> <br /><i>Figure 5: The Smartphone now has a tail. :-) The back panel has been replaced. The battery and SIM Card have been loaded.</i><br /><br /> <img src="http://www.smartphonethoughts.com/images/MPx200 AB06_RJ BackSmall.jpg" alt="User submitted image" title="User submitted image"/> <br /><i>Figure 6: The patient is all sewn up.</i><br /><br /> <img src="http://www.smartphonethoughts.com/images/MPx200 AB07_RJ FrontSmall.jpg" alt="User submitted image" title="User submitted image"/> <br /><i>Figure 7: It's time to power up the Smartphone to see, if the surgery worked or not. Nervous moments...The phone responds to the power switch and I see the familiar Hello Moto power up logo. :)</i><br /><br /> <img src="http://www.smartphonethoughts.com/images/MPx200 AB02_RJFinalResultSmall.jpg" alt="User submitted image" title="User submitted image"/> <br /><i>Figure 8: Phew...The Smartphone powers up! I didn't mess up anything. I see two bars instead of the usual one. The experiment is a S.U.C.C.E.S.S. :-)</i><br /><br /><span><b>But Does It Really Work?</b></span><br />Time to make a phone call and test the signal quality. I call my friend, and try to explain what I just did to my phone; the other side thinks I am a nut case. I ignore the remark and am now walking up and down inside my apartment, chanting <i>"Can you hear me now." </i>My friend can hear me loud and clear, no crackling sounds and no more missed words. <i>Yippee!</i> <br />:clap:<br /><br /><span><b>Next Steps</b> </span><br />I want to trim the 3" antenna wire down to half the current size. What do you think? Will it work as effectively as it is working now? Will I get better results if I make a spring coil roll (similar to the regular telephone cord connecting the handset to the base)? I would like to hear from some antenna experts. ;-)