Ricoh FT4460, Service Manual, Page: 79 / 413

28 February 1989
EDGE ERASE MARGIN
A 3 , A 4 4.5mm
9.5mm
14.5mm 1 9 . 5 m m
( D L T , L T )
( 5 . 5 m m )
( 1 0 . 5 m m ) ( 1 5 . 5 m m )
( 2 0 . 5 m m )
B4,B5
4 . 5 9.5 14.5 19.5
6 . 0 11.0
16.0
21.0
(HLT,LG,LT”R”)
(4.0)
(9.0) (14.0)
(19.0)
B5”R”, B6 4.5 9 . 5 14.5 19.5
A5”R”,A6
5.0
10.0
15.0 20.0
B6”R”
5.0
10.0
15.0 20.0
A6”R” 6.0
11.0 16.0
(HLT”R”)
21.0
(6.0)
(11.0) (16.0) (21.0)
O f f i c i a l
Postcard
3.5 8.5
13.5 18.5
4.1.3 Special Mode Erase
Erase is controlled by using 120 LEDs in 2.5 mm increments according to the
cassette data in editing. In centering, the registration start timing and erase
are controlled. The erase margins can be changed by SP Mode #39 (Center
Erase) and SP Mode #38 (Erase Edge) in 5 mm steps.
Center Erase Margin Standard = 20 mm
Edge Erase Margin Standard = 10 mm
4.1.4 Trailing Edge Erase
Normally, the erase lamps turn on after the trailing edge of the latent image
has passed. Therefore, a trailing erase margin cannot be observed on the
copy. Trailing edge erase ON timing is 0.04 seconds after charge corona OFF
timing. During enlargement or reduction, the trailing erase ON timing changes
according to the paper size and the reproduction ratio.
NOTE: The erase margins do not precisely correspond to paper size and
reproduction ratio as the erase lamps are 2.5 mm in size.
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