AMSTRAD PPC 512S - Page 8

~]f
Azimuth
waveforms
Index
burst
waveform
20 ms
|
"IT
Radial
alignment
waveforms
70 ms
120 ms
170 ms
Fig. 5.3 Alignment Waveform
(DAD)
5.6 Azimuth
Verification
(1)
insert
an alignment
diskette.
Seek
to
the
track specified
in the
azimuth column
of Table 4.1.
(2)
Set the
oscilloscope in
the same
conditions
as in
5.3., and set horizontal
deflection
to 2ms/div (DAD) or 0.5
ms/div
(CE).
(3)
Measure
as shown
below.
(4)
Confirm
that the
measured
value meets
the specifications
in the
azimuth column of
Table 4.1.
B
C
A
m
Ui LAI
D
IT
Azimuth
0'
waveforms
Case of B>C
(
+
)
B
—
C
Azimuth
=
-
x (A)
B
—
u
(A)
:
CE—
30'
DAD—
15'
Case
of OB(-)
C
—
B
Azimuth
*-
x (A)
a
Fig. 5.4
Azimuth Waveforms
5.7
Index Burst Verification
and Adjustment
(1)
Insert an alignment
diskette. Seek to the track
specified in the l/B
column of Table 4.1.
(2)
Set the oscilloscope time
base as follows: 1 ms/division.
(3)
Check that
the
time from
oscilloscope
start to the first data pulse meets
the l/B specifications
of Table 4.1. (DAD
SYSTEM).
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