Adjustable Sensor - Tally Dascom 7010 Series Maintenance Manual

(3) Adjustable Sensor

The adjustable sensor consists of the transparent sensor (upper sensor) and the reflective
sensor (lower sensor), and media passes between these sensors.
The transparent sensor and reflective sensor are used to detect the label stuck on liner and the
U-shaped notch on tag. While the reflective sensor alone is used to detect the black mark on
the bottom surface of tag. Both sensors are also used to detect the media end.
The transparent sensor consists of 1 LED (this is not a sensor actually but it acts as the
transparent sensor by the combination of the phototransistor in the reflective sensor). The
reflective sensor consists of 1 LED and 1 phototransistor.
U14
Custom IC
100 LEDMOVE_R
PFCNT2
99 LEDMOVE_T
PFCNT1
77
OPRS
U1 CPU
SENSMOVE
6
ANI1
DACIN
145
P25
DACCLK
147
P23
CS_DAC
- DO NOT adjust VR3 and VR4 on the Main PCB. (Leave them at the factory
setting condition.) If it is turned, media sensor sensitivity is changed and the
media detection will not be correctly made.
Transparent sensor (used for detecting the label or U-shaped notch):
When transparent sensor is used together with the reflective sensor (media sensor menu: See
Through), pin 99 (LEDMOVE_T) of U14 (Custom IC) goes "High", Q28 and Q9 turn ON and
the LED of the transparent sensor turns ON. The current flowing into the LED (the light amount
to be emitted) for detecting label is determined by U4 (D/A converter), U5B and Q10 under the
control of the U1 (CPU) and U14 (Custom IC).
When the liner (without label stuck on it) passes between both transparent and reflective
sensors, the light emitted from the LED of the transparent sensor reaches the phototransistor
of reflective sensor, passing through the liner.
+3.3V
R203
R120
U20B
R122
5
+
7
6
-
DO NOT
C83
ADJUST!
BA2904
U4 BH2227
AO1 1
12
DI
2
PESENSLED
11
AO2
CLK
10 AO3 5
CSB
Q8
DTA114EM
R202
Q27 Q28
2SC5658 2SC5658
R207
R124
DO NOT
ADJUST!
VR3 VR4
Q20
DTC114EM
U5B
5
+
7
R125
6
-
R126
C85 BA2904
C86
Caution
2-23
2-2. Operation of Control Parts
+5V
[Transparent Sensor]
Q9
J7
SA, Sensor U
DTA114EM
1
UP LED A
2
UP LED K
J22
DOWN
1
LED A
DOWN
2
LED K
+3.3V
3
DOWN TR C
4
DOWN TR E
Q21
DTC114EM
[Reflective Sensor]
Q10
2SC5658
R127
[Main PCB]
Media
SA, Sensor Bottom