Kurzweil K2000 Service Manual page 88

SECTION 4
DIAGS1_0.DOC 12113/92
0/1 and/or 254/255 limits too soon, there are 2 more adjustment
potentiometers on the Mod wheel assembly. If the display flickers or
changes to BATTERY or CONTROL PEDAL when the Mod Wheel is pulled full
forward or pushed full back, these pots should be adjusted.
C. Movement of the Controller Slider will cause uDATA SLIDER" to be displayed
along with a number between 0 and 255. Moving up from the down position
should make the numbers increase smoothly. Unless defective, the range of
the Data Slider will always be from 0/1 to 254/255.
D. If a properly connected control pedal is plugged into the Control Pedal
jack, moving it should cause uCONTROL PEDAL" to be displayed.
As
the
pedal is rocked forward, the numbers should increase from 0/1 to 254/255.
One common problem with control pedals is a range that won't go fully to
zero. This can often be corrected by an internal adjustment to the pedal,
either electrical or mechanical. Another common problem is non-linearity.
This can be recognized by the numbers increasing much more rapidly in the
higher range. Usually the only solution to this is replacement of the
potentiometer inside the pedal. See the K2000 Musician's Guide Appendix I
for more information about control pedal connection and testing.
E. If a switch pedal is plugged into the Switch Pedal 1 jack, the fourth line
will show "PEDAL 1" when the pedal is closed, and will go blank when it
opens. Some pedals (especially Roland) are normally closed, and open only
when pressed. Most others are normally open, and close when pressed.
The K2000 can use either type (as long as it is plugged in before powering
up) but the scanner diagnostics expect to see a normally open pedal.
After testing a normally closed switch pedal, the pedal must be unplugged
to clear the fourth line of the LCD. (This applies to Switch Pedal 2,
also. )
F. If a switch pedal is plugged into the Switch Pedal 2 jack, the fourth line
will show "PEDAL 2" when the pedal is closed, and will go blank when it
opens.
G. If the Alpha Wheel
is
turned clockwise slowly, the display will show "SPIN
KNOB" followed by a number that counts up (0, 1, 2, 3) and repeats.
Likewise if it is turned counter-clockwise, the numbers will count down.
Any other sequence indicates a problem-usually a bad connecting cable, but
possibly a bad switch contact.
H. If any button is pressed, the word uBUTTON" followed by its name will be
displayed. If it is one of the mode buttons, then its associated LED will
flash as well. It is normal for the LED associated with the PROGRAM
button to flash more brightly than the other buttons. If several buttons
have problems, the cause is usually the connecting cable. If only one
button is bad, then it needs replacing. Cable problems that seem to
disappear when the unit is disassembled are often due to a short circuit
caused by component leads on circuit boards puncturing the cable's
insulation. The ends of ribbon cable wires touching the conductive
coating inside the top cover can also cause improper operation.
I. Pressing any keyboard key down halfway will display the word "KEY" followed
by the key's note name (such as C#4 for the black key immediately to the
right of middle C) followed by the key's MIDI ID number (61 in this case).
This indicates that the "upper contact" of the key has closed. Pressing
lightly all the way down should display the same note name and MIDI number
a second time which indicates that the "lower contact" of the key has
closed. The two names/numbers should match. Most keyboard errors are
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