Service manual

A.7 GBR LINE CODE READ SYSTEMS OPTION
A.7a Introduction
The Line Code Recognition System is capable of decoding line code marks
that are on 1/8" or 1/6" spacing. There can be as many as 25 mark locations
in a bank with a possibility of two banks per each channel of Line Code
marks.
A Single Line Code Recognition card supports input information from two
probes. The second probe is a optional feature. The system is limited to
having only one of the two probes active at any one time. If more than one
channel of Line Code marks is required to be recognized on a single
document, each additional channel requires another Line Code Recognition
system.
The GBR Line Code reader uses an analog signal to read code as it passes
by the fiber optic sensor. The reader board is ‘intelligent’ because the
variables used to generate this analog signal are not hardwired into memory,
but can be modified through software. The reader can be adjusted to
account for variables such as:
Paper color changing from job to job
• Code not being printed to specification resulting in more reliable reading
from the 420T.
Reader Board Values that can be Adjusted Through The 420T Touchscreen
Refer to “Line Read Setup 4”.
• ·GAIN - controls the amplitude of the 0-5 volt analog signal.
• ·OFFSET #1 - controls the initial DC voltage added to the analog signal to
catch the lead edge of the page.
• ·OFFSET #2 - controls the DC voltage added to the analog signal when
reading the code.
• ·LAMP - controls the brightness of the reader probe.
• ·TRIP POINT #1 - controls the voltage level at which an interrupt will be
generated in a low-to-high voltage transition.
• ·TRIP POINT #2 - controls the voltage level at which an interrupt will be
generated in a high-to-low voltage transition.
For F30 set to BB+H read
420T V6LT OPERATOR & SERVICE MANUAL ISSUE 2009/06 Rev. 6/21/2011 SECTION A – PAGE 46
071-33370-400
INTRODUCTION