Epson STYLUS 4001968 Service Manual page 67

800 Service
STYLUS
4.1 OVERVIEW
This section describes procedures of the adjustment required when the printer is disassembled and
assembled after repair.
4.1.1 Precautions for Adjustment
You should refer to the precautions below when adjusting the printer.
Disconnect the power cable before when you attempt the adjustment. (Unless otherwise
specified.)
4.2 BI-DIRECTIC)NAL PRINTING ALIGNMENT ADJUSTMENT
The bidirectional printing alignment adjustment is required when the printer mechanism or the
main board is replaced. By performing this adjustment, a compensation value is determined for the
mechanical control as to compensate the deviation of print position, which may be caused by the
different print speeds due to the tolerance of the mechanical components, and the deviation of print
timing between odd-numbered lines and even-numbered lines in bidirectional printing. The
printer stores the compensation data in the EEPROM on the main board (C106 MAIN), and
referring to this data when the bi-directional printing is performed.
Set a stack of paper into the auto sheet feeder of the printer.
[Step 1]
[Step 2]
Execute BASIC on the PC and start the adjustment program "DNxxx.BAS".
[Step 3]
[Step 4] When the main menu of the program is appeared on the monitor, select "Bi-D Printing
Alignment" by entering "l".
[Step 5] Follow the instruction displayed on the monitor, and press ENTER key to start the
adjustment.
The printer prints the check pattern with a sample compensation value.
[Step 6]
Check the printed sample pattern, and if the character "H" is not vertically aligned in both
[Step 7]
odd-numbered lines and even-numbered line, enter the compensation value in the range
from -30 to +30, from the keyboard.
Positive compensation value:
Negative compensation value:
The printer print the sample pattern with the selected compensation value for
[Step 9]
confirmation. If the alignment is good, press "Y' to finish the adjustment.
[Step 10] Terminate theprogramby selecting ''3"at the main menu, and turn theprinteroff.
Because the compensation value specified within this program is not valid until the printer is
turned off, turn the printer off immediately after you have finish the adjustment.
Rev. A
Manual
Shift 2nd line to LEFT
Shift 2nd line to RIGHT
Adjustment
4-1