Teac FD-55 Series, Руководство по обслуживанию

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(5) TP5 (Read data)
Test point to observe the read data pulse.
The signal level at this TP is opposite to that of the READ DATA output
signal.
(Fig.317) Typical waveform of T P 5
Fig.317 shows the waveform at TP5 in normal data read operation.
In the FM method, 2F and IF intervals are observed, while 2F, 4/3F, and
IF intervals are observed in the MFM method. ^ . . .
Items
FD-55A
a
, p
FD-55G
2F interval 4ps, Norn.
2y s , Norn.-
4/3F interval
6y s , Uom.
3ys, Nom.
IF interval
8ys, Norn.
4ys, Norn. -
Pulse width
l±0.5ys
0 . 5±0.25ys
(Table 304) Read data pulse timing
(6) TPS (File protect sensor) - ~ - - -
Test points to observe the output of the file protect detection photo­
transistor.
The signal level at this TP is opposite to that of the WRITE PROTECT
output signal. When a disk with the masked write protect notch (write
327 -