Kurzweil PC3x, Руководство по обслуживанию

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4-16
Troubleshooting & Maintenance
Keyboard Problems
Keyboard Problems
Dead Keyboard
1. Run the Scanner Tests. If the tests pass, the problem is likely the result of a setting in the
Control Setup. Perform a Hard Reset to the unit or refer to the Control Setup sections in
the
Getting Started Guide .
2. Check the fl at ribbon cables connecting the keyboard Bass and Treble Contact Boards to
the Connector Board, locations J307 and J306 respectively. Be certain that the cables are not
loose or damaged.
3. Disconnect and reseat the cables.
4. Refer to the Connector Board schematics.
5. Check U1, IC Scanner M38869 on the Connector Board for keyboard signals.
6. Trace signal path.
7. Find and replace bad component(s) or order a board replacement.
Dead Note(s) or no velocity sensitivity
One or More in a Section
1. Remove related contact board.
2. Check the keyboard contact strip for dirt, damage or wearing. Clean dirty contacts with
denatured alcohol. Replace a damaged or worn keyboard contact strip.
3. Install keyboard contact strip.
4. If section is still dead, remove strip and check contact board for shorts, cold solder joints,
etc.
5. Find and replace bad component(s) or order a replacement board.