Access To Main Logic Board In Display Unit; Access To Keyboard Pcb; Keyclick/Bell Volume Adjustment - Facit 4431 Service Instruction

3.2 ACCESS TO MAIN LOGIC BOARD IN DISPLAY
UNIT
The user will need access to the main logic
board to alter the setting of jumpers described
in sections to and access in gained as follows:
Switch off the unit and disconnect from the
mains supply.
2 There are four slot-head fixing screws which
retain the display unit top cover. These are
located at the bottom of the cover, under the
lip, close to where the stand enters the dis-
play unit body. The screws can be accessed
from below by means of a short screw-driver.
To remove the cover the screws must be scre-
wed IN (clockwise) as far as they will go.
3 Grasp the lip of the cover on each side, pull
outwards and simultaneously lift the cover.
4 Access to the jumpers on the main logic board
is now possible.
5 Replacement of the cover is the reverse of
the removal. The retaining screws must then
be screwed OUT (anticlockwise) as far as they
wil 1
go.
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FIG 3.1
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3.3 ACCESS TO KEYBOARD PCB
The user will need access to the keyboard p.c.b.
to allow the setting of jumpers described in
sections and access is gained as follows:
Switch off the unit and disconnect the key-
board from the display unit.
2 Remove the two retaining screws at the right
hand end of the keyboard, and then remove the
end cap.
3 Slide out the printed circuit board (discon-
necting the loudspeaker lead if necessary)
and lift off the top plate.
4 The jumpers and associated components are to
be found along the top of the p.c.b.
5
Reassembly of the keyboard is the reverse of
the above. Ensure that the p.c.b. and top
plate slide in the retaining grooves in the
keyboard housing.
3.4 KEYCLICK/BELL VOLUME ADJUSTMENT
The audible tones produced by the unit are gene-
rated by a small loudspeaker mounted in the key-
board. The level of sound produced may be adju-
sted by rotating (by means of a small screw-dri-
ver) the SPKR VOL ADJ potentiometer. This is
located in the left hand top corner of the key-
board p.c.b.
1 Rear panel
2 Top cover
3 Monitor (CRT)
retaining screws
4 Front panel
5 Volume adj. pot
6 End cap screw
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