HP 8546A passcodes for flatness calibration 

I purchased a new HP 8546A ten years ago from the now Agilent test and
measurement group. Agilent/HP service told me today that they have
stopped supporting this EMI receiver.  It's only ten years old and the
adjustment is only 3dBs out.  This passcode is needed to enter the new
offsets.  I suspect that the passcode is the same on all HP8546A
receivers.  The system is made from two parts and it is the HP85462A
part that requires the passcode.
of specification.