Adjusting Laser Power - Canon LBP-CX Series Service Manual

Signal/command
Checkpoint
Approx. DC voltage(V)
Remarks
Red lead Black lead True
False
Laser heater drive command
1204-2
(LSRHD)
1204-4
0
15-30
Manual pickup roller solenoid
J210-4
drive command (MPUSD)
1210-5
0 24
PAPER OUT indicator drive
command
(PEMPL)
J201-3
1208-6 0 3-5
"'
Printer power ready signal
J202-5
.....
(PPRDY)
1208-6
5
0
=
p.
.....
Preconditioning-exposure
=
1207-1
0
command (PEXP)
1207-2
24-35
0
- -
Ready signal
(RDY)
1202-7
J208-6 0
5
READY /WAIT indicator drive
J201-2
command (RDYL)
J208-6 0 3-5
Registration shutter solenoid
J210-2
1210-5
0
24
drive command
(RGSD)
Scanner drive command
(SCNON)
1206-4 1206-2
0 5-15
Print counter drive command (TM)
J207-3
1207-4
0.1-0.15 0.04-0.06
Vertical sync request command
J202-9
(VSREQ)
1208-6 0 5
Table 7-5
(2) AC driver (AC controller and fixing roll'er heater safety circuits) signals
Signal/command
Checkpoint Approx. DC voltage (V)
Remarks
Red lead
Black lead
True False
.....
Fixing roller heater drive
=
Pulse
p.
J104-2
Jl04-1
24
i::
command (FSRD)
(10-20)
-
AC power supply for fan (FM 1) J102-l J102-2
Line voltage 0
TRUE while the main
switch is ON
"'
Triac Ql (voltage for both ends)
Line
Fixing roller heater ....
Jl0'.1-7 JlOS-3
0
=
p.
voltage
control
....
=
AC power supply for fixing
0
JlOl-1
roller heater (Hl)
JlOl-2
Line voltage 0
Controlled by Triac Q 1
AC power supply for transformer
J103-1
Line voltage
TRUE while the main
J103-2
0
(PTl)
switch is ON
Table 7-6
3. Adjusting laser power
Note:
Laser power adjustment should be made after
replacing the DC c-ontroller, the laser unit, or if the
following image defects arise: light image (I-1), dark
image (I-2).
(1)
Switch the power OFF.
(2) Remove the top cover (6).
1. If the multimeter does not make good contact, or
if the meter range is wrong, the power of the laser
cannot be measured accurately. Be sure to plug the
black lead into the black socket and the red lead
into the red socket.
(See I.A. in Ch. 4.)
(3) Open the plate over the access hole for the laser
driver checker on the laser and scanner unit.
( 4) Connect a digital multimeter to the laser power
checker (TKN-0198)
Set the range to 200 mV.
2. Adjust laser power as seldom as possible. Frequent
adjustment increases the chances of damaging the
laser chip.
COPYRIGHT
©
BY CAROii INC. CAllOll LBP·CX SERIES REV.2 JULY 1985 PRlllTED IN JAPAN (IMPRIME AU JAPON)
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