I want to set up a Bluetooth link between devices that are over 2000 feet apart. Yagi antennas for 2.4GHz that can connect to routers are available. A cheap Bluetooth dongle that can be easily taken apart can be found on DealExtreme (see the insides of one at http://we.easyelectronics.ru/Stress/prikruchivanie-usb-ustroystva-k-vnutrennostyam-noutbuka.html [In Russian] ). The cheap Bluetooth dongle has an antenna on its PCB. How can the internal antenna, with its single wire connection, be disabled and the external Yagi, with its coax wiring, be connected for strong signal strength?
This is an example of the type of dongle I'd like to modify. The antenna trace can be seen on the right side of the PCB.