UBI EasyCoder 601 XP – Service Manual Ed. 1
38
Chapter 7 Transfer Ribbon Mechanism
Adjustments
The intensity of the light emitted from the sensor is controlled by a
strap on P56 on the CPU board:
Strap fitted = higher intensity
Strap removed = lower intensity
The sensitivity of the receiver is controlled by the potentiometer
WR52 on the CPU board.
Before adjusting the sensor, check that the sensor and the mirror are
clean and free from obstructions.
A simple program can be used to check the ribbon end sensor, e.g.:
10
'RIBBON END SENSOR TEST
20
'INTERRUPT PROGRAM BY TYPING "X"
30
BREAK 1,88:BREAK 1 ON
40
ON BREAK 1 GOSUB 1000
50
IF (PRSTAT AND 8) THEN SOUND 100,50 ELSE BEEP
60
GOTO 50
70
END
1000
BREAK 1 OFF
1010
GOTO 70
RUN
Remove the transfer ribbon from the sensor's beam of light (e.g. by
pulling out a loop) and run the program. The printer should emit a
low sound.
Put back the ribbon into the beam and the printer should start to beep
with a high-pitch tone.
If the printer does not behave as described, remove the left-hand
cover and, with the power still on, turn the potentiometer marked
“RI-END” (WR52) at the upper edge of the CPU board back and
forth. If that does not help, fit or remove the jumper on P56.
If the sensor refuses to work, consider the possibility that the mirror
plate may be bent before discarding the sensor.
7.4 Ribbon End Sensor,
cont'd.
