Not sure if I posted this before..
Bluetooth range is about 20 meters.. But at some situations you may want to extend that range to longer distance.. the idea is to send the data to an external Bluetooth module (HC-6) next to the phone. that BT
module is further connected to wireless RF data transceiver.. The receiver should be the same type as the
RF Radio (not Bluetooth). If Bluetooth input is needed at the other side then just connect another BT module to the RS485 (TTL) out put of the receiving RF radio.
Some people asked me for more details.. In fact I didn't make much modifications to Erel's Bluetooth example, so it can be used AS IS.. On the other hand, the radio I am using now is a 2km RF data transceiver that can be found on Amazon for about $7. there are so many versions and brands but the basic functions are the same.. just make sure the one you buy has TTL interface so you can directly connect it to the RF radio.. Another thing you must cross the Rx/Tx wires, so that the Rx of the BT module is connected to the Tx of the radio.
In this drawing I explained some useful connections that are self-explanatory.
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