[Elecraft] KNB2 Component

[Sid Leben]

I just received the KNB2 option for the K2 #3863.

After checking out all the parts I have one discrepancy that I hope someone 
can help with.

"U3" is supposed to be an 8 pin IC microcontroller, # 12C509A 
(12C508A).  The only component not identified after the parts check is an 8 
pin IC, with a white paper label on top, labelled "NB102".

Is this the errant micro-controller "U3" or some other chip??

Thank you for your help.

Sid  KC2EE