Parts Exchange; List Of Test Points; Printed Circuit Board Exchange - AMSTRAD PC1640 Service Manual

3-7
List of
Test Points (See
Fig.
3-7)
Test Point
Signal
Name
r
TP
9-—
-4-
r
1 1 1
r
1
TP1
READ
AMP OUT
TP2
READ
AMP OUT
TP3
GND
TP4 STEP
TP5 READ DATA
TP6 INDEX
TP7 WRITE PROTECT
TP8
TRACK
00
TP9
GND
I
Fig.
3-7 Test Point Layout
4.
Parts
Exchange
4-1
Printed Circuit
Board Exchange
(See
Fig.
4-1)
4-1-1 Printed Circuit
Board
Removal
a)
b)
c)
d)
e)
Remove
the
drive
belt,
stretched
between
the spindle
pulley
and
the
DC
motor
pulley
by
rotating the spindle
pulley as the
direction
shown
in
Fig.
4-1.
Be
careful not to touch the inner surface
of
the drive
belt
and
the side
of
the spindle
pulley
and
DC
motor
pulley.
Disconnect the connectors. (LED,
P.C.B.,
Track
00
sensor,
DC
Motor
P.C.B.,
Stepping Motor,
Head
F.P.C.).
Unfasten
four printed
circuit
board
fixing
screws.
Remove
the
printed
circuit
board.
Remove
the insulating sheet.
Fig.
4-1
Printed Circuit Board Exchange
*
4-1-2 Printed
Circuit
Board Mounting and Adjustment
a)
Install
the insulating sheet.
b)
Fix
the printed
circuit
board
with four screws.
c)
Reconnect
the
disconnected
connectors, (LED,
P.C.B.,
Track
00
sensor,
DC
motor
P.C.B.,
Stepping
motor,
Head
F.P.C.).
d)
Place the drive
belt
over the
DC
motor
pulley
completely and
only
partially
on
the spindle pulley.
e)
By
rotating
the spindle
pulley, the
rest of
the
belt
will
fit
completely
over.