The Radio Information Board

I have a kenwood tm-742a tri-bander that the memory battery is good ( 2.8 volts ) but an hour after turning the 12 volts off and then back on , the freq's are gone , but if you let 12 volts hooked up and just turn the power off by the switch on the radio its OK ????????? doe's anyone have any hints ...

i have a kenwood tk-690 and a tk-6110 band spread of 42-50 mz and was wondering if it was possible to slide the vfo up alittle with no real issues - up to the 6-meter band up to 54 mz, ????????
any help
thanks
mike