Ricoh K-C3, Service Manual

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B245/B276/B277/B268/B269 Service Manual 18-Jan-06
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changing the ADF motor speed. Magnification in the main scan direction is done in the BICU
board, like for book mode.
Magnification in the sub-scan direction can be adjusted by changing the ADF motor speed
using SP 6006 5. In the main scan direction, it can be adjusted with SP 4009, like for book
mode.
Original Size Detection in Platen Mode
In the optics cavity for original size detection, there are four reflective sensors. The original
width sensors [A] detect the original width, and the original length sensors [B] detect the
original length. These are the APS (Auto Paper Select) sensors. Each APS sensor is a
reflective photosensor.
While the main switch is on, these sensors are active and the original size data is always sent
to the CPU. However, the CPU checks the data only when the platen cover sensor [C] is
activated. This is when the platen is positioned about 15 cm above the exposure glass, for
example while it is being closed. The CPU can recognize the original size from the
combination of on/off signals from the APS sensors.
If the copy is made with the platen fully open, the CPU decides the original size from the
sensor outputs when the Start key is pressed.