Teac FD-55 Series, Maintenance Manual

Page: 119 / 216

TPS(Read data)
READ DATA
1
n _
2
__mi___ J h
1
i_ r ^
LL
Asymmetry
IF interval
Trigger
(Fig.426) Measurement of asymmetry
(h) For a double sided FDD, execute items (e) through (g) for side 0
and side 1 heads respectively.
(i) If the value in item (g) or (h) is out of the specified range, adjust
according to the following procedure *
The adjustment can be done only for the PCBA versions or the PCBA
revision numbers with the variable resistor R5 on the PCBA MFD control.
No adjustment can be done without H5.
i) Adjust the variable resistor R5 so that the asymmetry takes the
minimum value while repeating IF write and IF read operations
alternately.
ii) For a double sided FDD, repeat the operation in item i) for
side 0 and side 1 heads alternately. The variable resistor shall
be so adjusted that both asymmetry for side 1 and side 0 heads
take the minimum value.
(j) if the values in items (g) and (h) are out of the specified range
in the PCBA without the variable resistor R5, or if the adjustment
iniitem (i) cannot be done sufficiently even if R5 is mounted,
following causes are assumed.
i) Leakage flux density in the environmental condition of the FDD
4081