[Kenwood] TS 690 PLL problem

[Mike and Alicia Fanning]

Hi all,
My Dad has a TS 690 that appears to be having trouble with the one or both
of it's PLLs.  He recently turned the rig on and the correct frequency
displayed for about 10 seconds, after which it went to all decimals and the
rig sent "UL" in CW.  Whenever you change bands, the new frequency is
displayed correctly again for about 10 seconds, after which all decimals
return and UL is sent again.  Problem is the same on all bands.  Any
suggestions where to start looking?  Is this a common problem for TS 450/690
rigs?

Thanks,
Mike, K4GU