Commodore MPS-801 - Carrier Return Operation; Service Precautions; Self Test

SERVICE PRECAUTIONS
1. Be sure to unplug the power cord from the outlet before removing the upper case.
2. Do
not try to move or apply undue force to the print head and carrier unit.
They can be moved manually by removing the ribbon cassette and pressing the top of the head
solenoid
to free the clutch. See page 27.
3. Since the enclosure material is plastic, it is recommended that the 6 screws which hold the upper
and
lower cases together not be overtightened.
4. Do not use lubricate other than the designated ones.
5.
To detach the parallel cable from the PCB, lift the connector housing and pull up on the cable.
The cable is secured by lifting the connector housing, inserting the cable, and then pressing the
housing down until it clicks into position. make sure the connection is good by pulling up on the
cable slightly.
6. The smooth side of an E-ring should face a rotating gear.
SELF TEST
This unit has a pre-programmed self-checking capability. The program may be used to test the print
head operation, print quality and printer mechanism (ribbon feed function, linefeed, etc.). The self-
test function is initiated by selecting "T" on the device selector switch.
NOTE: While in the self-test mode, communication with other devices is not possible. Do not operate
self-test without paper in the printer. The test will continue until the unit is turned off.
T 5 4
DEVICE SELECTOR SWITCH
Position "4" selects operation as device #4
Position "5" selects operation as device #5
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