I started by tearing the Mini down and seeing if it was even possible. Dell's service manuals for the Mini 9 are pretty decent and are all you need to take the system apart. You can view them here. Luckily, there's a bit of space around where the Bluetooth adapter is located. It wasn't much, but it looked like enough, so I ordered the smallest USB GPS receiver I could find. It's a nice unit with a SkyTraQ chipset and support for AGPS. Once I used the included utility to download an AGPS update into the unit, it gets a location fix in about five seconds after a reset.
Once I made sure the GPS receiver worked, I immediately took it apart to see just how small it could get. I was pleasantly surprised to see just how small it really is. Here's a picture of the GPS unit, the Bluetooth adapter, and a quarter for scale comparison.
I then started moving the Bluetooth adapter and removing the old mounting provisions for it, since they were now in the way. There was enough room, but just barely. If the GPS was another 2mm thick, it would not have fit. The GPS completely fills the space between the Bluetooth adapter and trackpad. There is a lot more space on the bottom of the laptop in the unused WWAN card area, but the GPS needs to be on top so that it has a view of the sky. A unit with a separate antenna may provide other mounting options, but I decided it would unnecessarily complicate things. Here is a shot from test fitting.
Next, I needed a 5v source to provide power for the GPS. Luckily the trackpad runs on 5v, and it's right there, how convenient! The power is on the outer two pins of the ribbon cable connecting the trackpad to the motherboard. In the picture below, ground is to the left and +5v is to the right.
Here is the GPS unit with the USB plug removed and wires soldered on instead to save space. The orange wires are connecting power and the blue data. You can also see that the sheilding foil has been removed from underneath the Bluetooth's new location.
A connection to the USB of the Mini was needed, and luckily the WWAN mini PCI-e connector's USB lines are active. I was able to run the data lines through the hole in the motherboard for the WWAN card mount. I connected the USB data lines to pins 36 and 38 of the unused mini PCI-e connector.
So then I double and triple checked the wiring, put some tape in for insulation and put everything back together. I was quite pleased when it started right up, and now my Mini knows where it is! The satellite reception through the case of the Mini is excellent.
Fitment is perfect, you cannot tell it was modified without opening it up. There are no bulges or other outward indications that anything has been changed.
The GPS receiver is turned on and off by a Team MRB Power Isolator Module.
Keep in mind that when you try something like this, you very well could break your computer. If that is something you couldn't live with, don't even attempt it. Also, it helps to have electronics and soldering experience. That being said, are there any questions?
Tom Beauchamp
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Questions and Answers
Lots of good questions, I'll try to answer most of them here.
strider_mt2k wrote:Can you detail the exact solder points on the mini PCIe area?
USB_D+ and USB_D- are available on pins (pads, more accurately) 38 and 36 of the mPCI-e connector. It is labeled with pad numbers on the motherboard. There is no 5v power on a mPCI-e connector, so that's why it was sourced elsewhere.
strider_mt2k wrote:How are drivers for that GPS module?
Like all of the other GPS units I have used, this one is based on a USB to Serial adapter from Prolific. The driver is very small and once installed the device just shows up as a COM port (COM8 for me).
strider_mt2k wrote:What GPS software are you using?
It will work with anything. It's just running the GPS demo utility that came with the device in the pictures. I'm currently looking for a good PC based navigation software as well as something that does the same kind of location based services that the Google Maps / Windows Live applications for Pocket PC do on my phone. I've used MS Streets & Trips in the past, found it just ok. Microsoft MapPoint has a lot more business related functions like statistical analysis but is too cluttered for normal driving directions, IMO (It makes a sweet map of your war-driving logs though). My current navigation solution is Delorme StreetAtlas, which works pretty well.
UncleRunkle wrote:is there any possibility of using the WWAN mini PCI-e so one could just put a mini PCI-e usb hub in there? Or did Dell completely deactivate the WWAN?
I can't say for certain on that one. I did not have a need for the PCI-e connection, so I just checked and implemented my connection to the USB lines. The 1.5v bus lines on the PCI-e connection did not have power, so I would wager that the slot cannot be made fully operational. Also, there is no 5v power on a mPCI-e connector and you need that to make a standard USB port, so it couldn't be just a plug-in operation.
jw8725 wrote:Hi great mod but how would this affect battery life?
I've only had it running since this morning, but I used my Mini intermittently throughout the day and did not notice a negative impact on battery life. Obviously it will have shorter runtime with the GPS on, but it's a very low power device, so it doesn't seem to have too great of an impact.
jw8725 wrote:Is the GPS always switched on or does it only operate with the software?
I have developed the Team MRB Power Isolator Module, and this GPS unit is turned on and off by turning the Bluetooth on and off. Read here for more information.
