Epson FX-80 Technical Service Data page 8

PRELIMINARY SERVICE CHECKS
fContlnued)
MISCELLANEOUS ADJUSTMENTS
HEAD
DRIVER PULSE WIDTH
ADJUSTMENT
Connect
the input of a
scope
to pin
36
of
the Micro-
processor
IC
(3B).
Set the horizontal
sweep
to .1ms,
trigger
to positive edge.
Use
the Printer self-test
mode
(hold
LF
Button
down
while switching
Printer
On) and
adjust the
Pulse
Width
Control (VR1)
for
a pulse width
of
.62ms,
See
Figure
1.
Figure
1
PTS
SENSOR BOARD ADJUSTMENT
Connect
the
input of
a scope
to
TP
PTS,
set
the
horizontal
sweep
to .5ms,
trigger to positive
edge. Use
the
Printer self-
test
mode
(hold
LF Button
down
while switching
Printer
On).
Loosen
the screw holding the
PTS
(Position Timing
Signal)
Sensor board
to
the
right
side
of
the Carriage Motor
(M3).
Use
a screwdriver
in
the
slot
provided
to
adjust the
PTS
Sensor Board
for
a pulse cycle
of 2.1ms, or a
50%
Duty
Cycle while
the Printer
is
printing
in
both
directions.
See
Figure
2.
Figure
2
HOME
POSITION
SENSOR ADJUSTMENT
Loose
the
HP
(Home
Position) Sensor
screw.
Use
a small
flat
screwdriver
to
move
the notch
at
the front of the
HP
Sensor
Board.
Move
the
notch
to
the
left
to
move
the
margin
left
or to the
right to
move
the
margin
right. Install
the
Ribbon
Cartridge
and perform
a
self-test
to test the
margin
position. Repeat
this procedure
until
printing
begins
at
the desired position
on the paper, tighten the Sen-
sor screw.
TIMING BELT ADJUSTMENT
Loosen
the
adjustment screw on
the belt tension
plate.
Tighten the
belt
until
no more
than
1/4
inch
movement
oc-
curs
on
the Printhead
when
it
is
at
either
end
of the carriage
shaft and
the
belt
is
pressed inward.
Tighten the
adjust-
ment
screw on
the belt tension
plate.
Run
the
printer
in
self-test
mode
and
note
the distance
between
characters.
The
distance should be
the same.
If
not,
check
the timing
belt
by substitution and perform
the carriage motor
adjust-
ment.
CARRIAGE MOTOR ADJUSTMENT
Loosen
the
left-front
and
right-rear
screws on
the Carriage
Motor
(M3) base. Slide
Motor
M3
toward
the
front of
the
Printer to
decrease the gear
lash.
This
is
done
to
MINIMIZE
the gear
lash,
without locking the gears
tightly together.
Slide the
motor
(M3)
toward
the rear of the Printer to
in-
crease the distance between the gears. Tighten the screws
of the Carriage Motor base and
set the Printer
in
self-test
mode
to verify
consistent speed
of
the carriage assembly
in
both
directions.
PRINTHEAD
ADJUSTMENT
Remove
the Printhead (HD) and
the Ribbon Mask.
Reinstall
the Printhead
and
lock
it
into position with the Ribbon
Mask
off.
Turn
the rear carriage shaft
until
the widest
portion of
the hole
on
the
left
end
of
the shaft
is
upward.
Insert a thin
screwdriver through the hole
to hold the
shaft
in
position
and
loosen the
nut
at
the
left
end
of the shaft. Set the
Head
Adjustment
Lever
to center position and
hold
in
place.
Move
the Printhead to the middle
of the shaft
and
insert a
0.6mm
Feeler
Guage
between
the Printhead and
the
Platen.
Turn
the shaft forward
or
backward
until
the gap between
the Printhead and
Platen
is
correct.
Hold
the shaft
in
place
and
tighten the nut on
the
left
end
of the shaft.
Check
the
adjustment
by gauging the gap
at
the
left
and
right
sides
and
at
the center
of the
Platen.
Move
the head adjustment
Lever toward
the Platen
and remove
the Printhead.
Re-
install
the
Ribbon Mask
with a
0.3mm
gap between
the
mask and
the Platen
and
tighten the two screws on
the
mask.
Reinstall
the Printhead and check
for a
gap
of about
0.1mm
between
the
Ribbon Mask
and
the Printhead.
Re-
install
the ribbon cartridge
and perform
Printer
self-test
with the
Head
Adjustment
Lever
set to mid-position.
The
print
should be
clear
and
dark without the wires
of
the
Print-
head
perforating the paper.
DIP
SWITCHES
O
O m
m 2
SWITCH
SW-1
ON
OFF
r-
£
x z
1-1
Column
length 132 characters
80 characters
§
/line
/line
1-2
ZERO
Font slashed
not slashed
1-3
Paper empty
Inactive Active
detector
1-4
Input buffer Standard ASCII
Accessed
inactive
1-5
Character
mode
Emphasized
Standard
Power
ON
INTERNATIONAL CHARACTER
SET DESIGNATION
SW1-6 SW1-7
SW1-8
USA ON ON
ON
England
ON
OFF OFF
France
ON ON
OFF
Germany ON
OFF
ON
SW1-8 SW1-7
SW1-8
Denmark
OFF ON ON
Italy
OFF
OFF ON
Spain
OFF
OFF OFF
Sweden OFF ON
OFF
SWITCH
SW-2
ON
OFF
2-1
Select
Mode
Fixed Select
Can
be selected
by
Computer
2-2
Buzzer Buzzer
No
Buzzer
2-3
Lower margin Margin No
Margin
one
inch
2-4
Auto
line
feed Auto
L ine
Feed
Line feed from
with Carriage Host
Computer
Return
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