arduino nano replacements #arduino


HI  all  
I'm facing a problem with my ubitx V5  i can't change the frequency or going trow the Sub Menu program i changed the   KNOBE encoder the same problems the frequency is frozen and the menu too so have decided to change the Arduino board.   

so please advice how I can do it step by step if anyone can help how I will proceed and what are the steps. to follow  .   

Best regards