Custom Audio Electronics VK80, Руководство пользователя

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11 ALIGNMENT
Device is provided with sensors for the use of alignment notch in order to handle roll of tickets with pre-printed ields and
a ixed length.
The alignment notch may be formed by
•
black mark printed on paper, for VK80 200 REAR, VK80 200 LAT models (see par. 8.6);
• gap between two labels, for VK80 300 models (see par. 8.7).
The alignment sensors assembled on printer, are “relection” sensors: this kind of sensor emits a band of light and detects
the quantity of light relected to it.
The presence of the notch is therefore detected by the amount of light that returns to the sensor, considering that the light
is relected by the white paper and absorbed by the black mark.
o use tickets with labels with gap, the sensors on VK80 300 models are used as “transparence” sensors. In this case, one
of the two sensors coupled two by two, used as transmitter sensor, emits a beam of light and the quantity of light which
reaches the opposite receiver sensor is detected.
The presence of the gap is detected evaluating the amount of light that arrives to the opposite sensor, considering that the
paper doesn’t allow the beam of light to reach the receiver, whereas a gap lets the light to reach the receiver.
The following paragraphs show how to correctly set the coniguration parameters of device in order to assure the alignment.
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