Be very careful to scrape towards the edges of the PCB to avoid damaging the other smd components on the board. It is easier than you think, all you have to do is find a sharp utility/hobby knife, and simply SCRAPE IT OFF THE PCB.

Now you can see why the range is somewhat limited!! Ok, bite the bullet, because this has got to come out, and you're gonna remove it. This is the antenna which you're using at the moment. On the side of the PCB with the 2 chips and a 13MHz crystal, you will see a hook-shaped silver line at the top of the board (I've marked this in YELLOW on the picture). If you are ok to continue (a small glass of whiskey will help!), then we'll move to the next stage. Having second thoughts now? If you aren't confident with a soldering iron, simply pop everything back together again, and forget this mod. OK, so now we're inside, and you should be looking at a small PCB (printed circuit board).

Your old CB antenna WILL NOT WORK! So - if you are happy to try something (at your own risk), and want to get a significant increase in usable range for you dongle, go to the next step, but remember, the end result doesn't look pretty, but performs brilliantly! This figure then has to be divided by 4 to give us a quarter wave antenna, which will be 30mm in length - THIS LENGTH IS CRITICAL!!! 25mm or 35mm will just make it less efficient (Lower range).

As Bluetooth devices work at frequencies of around 2450MHz, the formula will give you an antenna length of +/- 12cm. I was surprised to find other 'range extender' mods on the net, which did not mention this important fact! (One site had someone who had attached a 'foot long piece of wire' onto his USB dongle and was wondering why it didn't work very well!!!) There is a recognised formula for calculating antenna length/frequency, which is (without going into detail) 300/frequency - i.e. Being a radio ham, I am familiar with antennas, and know how critical it is to get the CORRECT antenna length, if your signal is going to be efficient. The victim was a $8 USB Bluetooth dongle, with a usable range of about 10 metres (less through walls). This modification is something I came up with after struggling to get a reasonable range from my Nokia N82 to my computer in another room.

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