This morning while in climb out in B29s I switched to F3 mode, I was unable to leave F3 mode. I tried F1,F4,F6,1,2,3,4,5,and 6 no help. None of the keys seem to work /would not bring up radio bar alt F4 would not work. On landing I could not and sortie using clipboard. I went to training area and everything seemed to work fine any suggestions?