Kurzweil Mark Pro 2i, Service Manual

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Mark Pro TWOi
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Keyboard
When a keyboard key is pressed, the key’s musical pitch should be shown in the display. The
first character should be the note name .The second character should be blank for white keys or
a “high o(sharp sign) for black keys. The third character should be the octave number from 0
to 8. Thus Middle C will be shown as “C 4”
Besides the key name, the 3 decimal points in the display reveal important information about
the rubber switches under the key being pressed. When the key is pressed partially, the left
decimal point will indicate that the first rubber switch and made contact. When the key is
pressed further, the middle decimal point indicates that the key is pressed further, the middle
decimal points indicates that the second rubber switch has also made contact. Thus when a key
is pressed slowly, the following sequence should be observed exactly 0.
Blank Display -> Correct Key name and left decimal point -> Correctly Key name and left and
center decimal points
If the correct key name and only the center decimal point lights, then there is a defect associated
with the first switch. If all 3 decimal points light, then either more than one key is processing at
once or there is a short circuit in the connecting or on the connector.
Switch Pedals
If a single switch pedal is plugged into the SW jack, operating it should case a response in the
display. For Kurzweil pedals , pressing the pedal should cause “S1C” to be displayed while
releasing it should cause “S1o” to be displayed. Other vender’s pedals may cause the opposite
response. If a dual pedal is plugged in, then the Sustain (right) pedal should display as
described above. The Soft pedal(left) should cause “S2C” and “S2o” to display. As with the
buttons , the display should respond immediately and without flickering if pedal working
properly.
Power Problems
Dead
1. Before opening the unit, verify the following: