Roland HandSonic HPD-20 Service Notes page 21

Sep. 2013
5. CONTRAST/ENC
fig.test-7.eps
This tests the operation of the encoder at the lower left of the panel and
changes in the contrast of the LCD screen.
1.
Slowly turn the encoder at the lower left of the panel clockwise, one click
at a time.
2.
Verify that the triangular graphic in the meter at the center of the screen
moves to the right a little at a time and the screen contrast simultaneously
becomes progressively deeper.
When the value at the bottom of the screen reaches 50, the message
RIGHT OK! is displayed.
3.
Slowly turn the encoder counterclockwise, one click at a time.
4.
Verify that the triangular graphic in the meter at the center of the screen
moves to the left a little at a time and the screen contrast simultaneously
becomes progressively fainter.
When the value at the bottom of the screen reaches 0, the message LEFT
OK! is displayed.
5.
Press F3 (NEXT) to advance to the next test item.
6. BACKLIGHT/ENC
fig.test-8.eps
This tests the operation of the encoder at the upper right of the panel and
changes in the brightness of the LCD backlight.
1.
Slowly turn the encoder at the upper right of the panel clockwise, one
click at a time.
2.
Verify that the triangular graphic in the meter at the center of the screen
moves to the right a little at a time and the backlighting simultaneously
becomes progressively brighter.
When the value at the bottom of the screen reaches 50, the message
RIGHT OK! is displayed.
3.
Slowly turn the encoder counterclockwise, one click at a time.
4.
Verify that the triangular graphic in the meter at the center of the screen
moves to the left a little at a time and the backlighting simultaneously
becomes progressively darker.
When the value at the bottom of the screen reaches 0, the message LEFT
OK! is displayed.
5.
Press F3 (NEXT) to advance to the next test item.
7. D-BEAM
fig.test-9.eps
* The relation between the on-screen values and the height varies according to the
surrounding environment (brightness and color of illumination).
The test program automatically checks whether or not the D-Beam value
is 0 (checks the optical receptor circuit when the emission of D-Beam
light is stopped).
If no problem is found, execution advances to the next screen.
Hold your hand over the D-Beam; the value displayed on the screen
changes.
fig.test-10.eps
1.
Pull your hand away from the D-Beam and verify that the value becomes
350 when your hand is 25 centimeters from the panel surface.
If the value does not reach 350, press + to adjust the Calib Level.
Raising the value of Calib Level too high at this time can make the unit
overly sensitive to environmental effects. Adjust using + and -, being
careful not to raise the value higher than necessary.
* This calibration value is stored in memory in the HPD-20 and is not erased by a
factory reset.
2.
Bring your hand up to the D-Beam and verify that the value reaches 1023
when your hand is 5 centimeters from the panel surface.
fig.test-11.eps
3.
Pull your hand away from the D-Beam and verify that the value
decreases smoothly.
When the value is 350 or less, execution advances to the next test item.
HPD-20
21