TSC TDP 248M, Service Manual

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TTP-248M/2410M Bar Code Printer
Service Manua
l
3.11 Sensor Circuits
Ribbon Near End Sensor
The voltage of sender (PIN 3) is about 1.18V (1.17V~1.19V).
When the sensor detects the black area, the voltage of receiver (PIN 2) is
≧
2.10V.
When the sensor detects the white area, the voltage of the receiver (PIN 2) is
≦
1.26V.
1
2
3
4
JP2
RNE
VCC
GND
R64
100
R25
10K
12 13
U3F
74HC14
R67
100
U2/119
Fig. 3.9 Ribbon Near End Sensor Circuit
GAP Sensor
1. Selecting MANUAL GAP and adjust the tension.
When the tension increases, the voltage of the sender (PIN 5) will decrease;
when the tension decreases, it will increase.
If adjust the voltage of PIN 5 between tension 000~255, it will alter between
4.4V~3.7V.
2. Selecting AUTO GAP to detect label will get a value of tension, and then
selecting the MANUAL GAP.
When sensor detects the paper:
LCD displays Not Through the voltage of receiver (PIN 2)
≦
2.10V
When sensor detects the gap or does not detect paper:
LCD displays Through the voltage of receiver (PIN 2)
≧
1.26V
Black Mark Sensor
Selecting MANUAL Bline, and adjust the tension.
When the tension increases, the voltage of the sender (PIN 6) will decrease;
when the tension decreases, it will increase.
If adjusting the voltage of PIN 6 between tension 000~255, it will alter between
4.4V~3.7V.