Kurzweil K2600 Series, Service Manual

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Troubleshooting
Keyboard Problems
5-13
Keyboard Problems
Keyboard velocity problems
1. Perform a Hard Reset to eliminate programming problems.
2. Refer to the Scanner Board schematics.
3. On the Scanner Board, check J703 for the proper jumper setting.
4. Check the signals at U5 and U6 on Scanner Board.
Dead Keyboard
1. Check the fl at ribbon cable connecting the keyboard Bass and Treble Contact Boards to the
Scanner Board, location J704. Be certain that the cable is not loose or damaged.
2. Disconnect and reseat the cables.
3. Refer to the Scanner Board schematics.
4. Check the signal activity at U1 (M37451) on the Scanner Board.
5. Trace signal path.
6. Find and replace bad component(s) or order an Scanner Board replacement.
Dead Note(s), One or More in a Section
1. Remove related contact board.
2. Check contact strip for dirt, damage or wearing. Clean dirty contacts with denatured
alcohol. Replace damaged or worn contact strip.
3. Install contact strip.
4. If section is still dead, remove strip and check contact board for shorts, cold solder joints
or open diodes.
5. Find and replace bad component(s) or order replacement board.
Mechanical Noise
1. Check keyboard for broken key weights, support brackets, or ripped contacts.