Appeal No. 97-3453 Page 7
Application No. 08/475,374
The examiner makes the following observation about
Ottesen.
Ottesen ... provides a bias servo loop for a
magneto- resistive head. FIR bandpass filter 20 and
RMS amplitude estimator 24 measure the second
harmonic distortion of the reproduced signal.
Decision circuit 26 compares the second harmonic
distortion with a reference 28. Current driver 12
adjusts the bias current based on the output of
decision circuit 26. (Id.)
He concludes that it would have been obvious to combine
Ottesen with Admission “to provide dynamic control of a
reproducing head, to maintain it at an optimum operating point
....” (Id. at 5-6.)
The examiner rejects claims 5, 12, and 14 as obvious over
the combination of Admission in view of Ottesen “as applied to
claim[s] 2, 11, 13, and 15 above,” (id. at 6), further in view
of Tin. He begins the rejection by admitting that the
combination “does not disclose delaying data with respect to a
reference clock signal.” (Id.) The examiner observes that
Tin “provides a reference clock generator 12 and a delay
circuit 20. As depicted in Figure 4, the time interval T
corresponds to a delay between recording an elementary
information on tape by head 41 and reproducing the same
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007