Epson LQ-2550 Technical Manual page 111

3 5
30.53
2.3.4.3 VR1/VR2 Reading Circuit
Figure 2-60 shows the VR1/VR2 reading circuit. The values (voltages) set by VR1 and VR2 are used
to control the corrections for bidirectional printing in the LQ and draft modes. VR 1 is used for
bidirectional printing in the LQ mode, and VR2 is used for bidirectional printing in the draft mode.
NOTE: Refer to Section 4.3.6 for adjustment of VR1 and VR2.
SUB CPU
(7 B)
Table 2-40 shows the relationship between the VR l/VR2 value and the terminal voltages at AN5/AN6.
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Table 2-39. 35 V Line Voltage and ANO Voltage
35 V Line Voltage [V]
1
\
R 7 5 VR2
R83
T
Figure 2-60. VR1/VR2 Reading Circuit
Table 2-40. VR1/VR2 Values and AN5/AN6 Voltages
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3 . 8 9
3 . 3 9
V
AREF
VR2:DRAFT FONT Bi-d.
M A X . - M I N . [ V ]
3 . 6 8 - 1 . 4
2 - 6 5
REV.-A
ADJUSTMENT
ADJUSTMENT
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