AdamaDBrown
05-01-2007, 09:10 PM
I thought I'd share a trick I found that can significantly increase two important measures of performance on the Cingular 3125/Qtek 8500 and all related smartphones.
I have a Qtek 8500, and awhile back it suddenly stopped holding a signal with the internal antenna. It would, however, still hold a signal with an external antenna. Faced with the alternative of trying to send a second-hand, eBay refugee unit flashed with a 3rd party ROM in for warranty service, I decided to try and repair it myself.
Thus, what I did was to remove the back casing, and attach a single strand of rosin-core electronics solder to the internal antenna. The other end I trimmed down to a point so that it would fit, and poked it in to the external antenna jack, so that it would contact the center pole of the jack. I then had to trim a small arch out of the rubber cap that goes over the antenna port to let it fit back on. It's also important not to let the wire touch the exterior brass contact of the antenna jack, otherwise you'll get no signal, and an intermittent contact may cause your phone to reboot. Using some tape to cover this up is a good method, or you might try insulated wire.
After everything was said and done, not only did it work again, but I experienced a fairly significant boost in the signal strength. It now almost always shows a full four bars, where before I would get two, maybe three. This has also led to an increase in battery life, since it doesn't need to use as much power transmitting. I'd assume this boost is because the original connection relied on a somewhat lossy method of attaching to the antenna: it ran through a very thin motherboard trace, then into a low-grade copper plate, which had the antenna's end pressed up against it with a small screw. The downside of this whole project is that the external antenna port is no longer useful for its original function, unless you want to disassemble the phone and remove the wire. I certainly wouldn't recommend it for everybody, but if you're ambitious, it might give you a nice upgrade.
Now, I haven't tested it, but it may also be possible to do this without taking over the external antenna port, by running a wire directly from the internal antenna to some part of the internal antenna connection. I wouldn't want to speculate too much, though, as it's something that would have to be tested.
I have a Qtek 8500, and awhile back it suddenly stopped holding a signal with the internal antenna. It would, however, still hold a signal with an external antenna. Faced with the alternative of trying to send a second-hand, eBay refugee unit flashed with a 3rd party ROM in for warranty service, I decided to try and repair it myself.
Thus, what I did was to remove the back casing, and attach a single strand of rosin-core electronics solder to the internal antenna. The other end I trimmed down to a point so that it would fit, and poked it in to the external antenna jack, so that it would contact the center pole of the jack. I then had to trim a small arch out of the rubber cap that goes over the antenna port to let it fit back on. It's also important not to let the wire touch the exterior brass contact of the antenna jack, otherwise you'll get no signal, and an intermittent contact may cause your phone to reboot. Using some tape to cover this up is a good method, or you might try insulated wire.
After everything was said and done, not only did it work again, but I experienced a fairly significant boost in the signal strength. It now almost always shows a full four bars, where before I would get two, maybe three. This has also led to an increase in battery life, since it doesn't need to use as much power transmitting. I'd assume this boost is because the original connection relied on a somewhat lossy method of attaching to the antenna: it ran through a very thin motherboard trace, then into a low-grade copper plate, which had the antenna's end pressed up against it with a small screw. The downside of this whole project is that the external antenna port is no longer useful for its original function, unless you want to disassemble the phone and remove the wire. I certainly wouldn't recommend it for everybody, but if you're ambitious, it might give you a nice upgrade.
Now, I haven't tested it, but it may also be possible to do this without taking over the external antenna port, by running a wire directly from the internal antenna to some part of the internal antenna connection. I wouldn't want to speculate too much, though, as it's something that would have to be tested.