[Kenwood] TS-690 serial numbers

[Lynn Baustian]

Does anyone know how to figure when a TS-690s was manufactured.  I am going 
to look at one tomorrow and would like to know all I can before hand.  When 
were they first produced and when did the manufacture period end and how 
does it relate to the serial number.  One would think that someone would 
have a table or spreadsheet with service bulliten notes etc.

Any help in advance would be greatly appreciated.  Thanks......Lynn  WA7ADY