I entered digital side of the electronics with this project that I am currently ripping my hair off. It is a APRS TNC as intructions are given by Mobilinkd(Hacking | Mobilinkd | Highly mobile packet radio). I learned almost everything about arduino's those required to make this work.
I made the TNC as instructions suggested and it works like charm when it is connected to PC. Sending and recieving packets correctly.
Then I tried to connect a HC-06 Bluetooth module to hardware serial of arduino nano to make the connection wirelessly so an android phone can be used.
Software comes with an .hex file and I couldn't find the source code. Even If I could find I am not sure how well my C to understand it but as far as I know TNC serial connects at 38400 baud. As I configured HC-06 to 38400 baud, my pc started to recive the APRS packets that has been decoded by the TNC.
Recieving is perfect but I cannot send packets and transmit it by my Radio. whateven I do I could not get it working. BT module was connected by a voltage divider. Then I used a Logic converter to make sure everything is right on the RX side of the nano but no use.
I tried another Bt modul HC-07 it did not even recieved. RX led on the nano doesnt blink when I transmit. and to make sure I correctly connected BT Rx Tx oposition to Nano hardware serial pins.
I cannot make any sence out of this situation. After hours of research, I checked every problem that has been similar to what I experience and non of the suggestions worked on my bread board.
Finally I gave up and asking you folks about your suggestions since I and internet is out of ideas. Thank you all for your time.
Ps: I even tried to fix the module according to this when it was clear my module was different. (Getting Bluetooth Working with JY-MCU BT_BOARD V1.06 | MCU on Eclipse)