Converting byte data to hex and then Sending HEX values via Arduino serial

nrkhara:
But it still sends '46' for the received char 'F' and '42' for character 'B'. I need to send '15' for the received char 'F' and '11' for 'B'.

I suspect you have not described your requirement properly.

Can you post an example of a message that you receive and a corresponding example of what you want to send.

...R