Dual C 839 RC Service Manual page 23

Mechanical section Fig. 14
General information
The item numbers listed refer to the list of spare parts below and
to the exploded diagrams. Before removing the various assemblies,
the power switch must beswitched off.
Removal or replacement of assemblies and adjustment.
1. Top cover plate
Remove the two fillister-head self-tapping screws 114 at the
rear of the unit and remove the top cover plate 113.
2. Bottom cover plate
Remove both fillister-head self-tapping screws 114 and the
hexagonal self-tapping screw 98 at the base of the unit and
remove the bottom cover plate 112.
3. Head cover plate
Loosen the two screws 78 and remove the complete head
cover plate 77.
4. Frame together with stop keys, visor
Press the complete frame 75 to the right and left lightly to
the centre and then remove it from below. Remove the
frame, withdraw plug 0 from the motor electronic system.
Withdraw the visor 50 from the front. When refitting, ensure
that the bearing 42 is correctly positioned.
5. Front trimplate
Remove the head cover and frame as described above. Re-
move all rotary switches, pushbuttons and the two lock
washers 146. Unscrew the 3 fillister-head self-tapping screws
114 from the base of the unit and then withdraw the front
trimplate 100 from the front.
6. Drive mechanism complete
Remove the cover plate, head cover and frame as described
above. Remove the counter belt and withdraw the female
multi-point connector Q from the motor electronics and G
from the baseplate. Unscrew the 4 machine screws 135, lift
the drive mechanism approximately 10 cm, withdraw the
black earth lead from the power section board and remove
the drive mechanism from the top.
7. Motors
When the drive mechanism has been removed, remove the 4
machine screws 3 and remove the cover panel. Remove the
drive belt (capstan). Unscrew the 3 machine screws 25 and
remove the motor fixture. Unscrew the machine screw 30,
remove the motor leads from the multi-point connector and
wiring harness and then remove the motors.
When refitting, ensure that the motors are correctly positioned
(figure 14). The tape wind belt must be pressed downwards
(refer to figure 15) through the tape wind motor drive pul ley.
Refitting involves the reverse procedure.
Fig. 15
8. Drive belts Fig 16
Replacing capstan belts: refer to the description of the motors.
Replacing the tape wind belt: remove the complete motor
fixture by removing the 3 machine screws 25. The tape wind
belt should then be replaced (refer to figure 15).
9. Flyvvheels
Note: flywheels must only be replaced in pairs. Remove the
motor fixture as described in the section entitled "motor".
Replace the flywheels. When refitting, ensure that the washers
are replaced in the correct order (figure 16). Fit the flywheel
using the adhesive magnetic ring at the right. The axial play
of the flywheels, 0.2 — 0.5 mm, may be set at the screws 29.
10. Bulb (cassette compartment lighting)
Loosen the machine screw 32, remove the retaining bracket
and replace the bulb 34.
10,5- MMIn (Motom mit grünem Gehäuse)
r
«.- 9:5 -41 MM (Motoren mit schwarzem Gehäuse)
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