Kurzweil CUP2, Руководство по обслуживанию

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Power Problems
Dead: LEDs not lit
Before opening the unit, verify the following:
1. The AC outlet is supplying power.
2. The AC cord is good and properly connected to the unit.
3. Check fuses. Follow Steps 4 and 5 to access them.
4. Open the unit. Follow the procedures on pages 4-2 through 4-3 to open the panel.
5. Check the voltages at the connectors listed below to identify the defective board and/or
component(s).
•• J23 on the Interface Board, page 7-9, and check the fuses at F1 and F2.
•• J24 on the Interface Board, page 7-9.
•• J501 on the Audio Board, page 7-10.
•• J502 on the Audio Board, page 7-10, to J15 on the Interface Board, page 7-9.
•• J25 on the Interface Board, page 7-9, to J23 on the Engine Board, page 7-7.
Audio Problems
No Audio
1. Run the Scanner DIAG tests to check the volume control operation.
2. If a volume pedal is plugged in, make sure it is not set to minimum. Or, power-off, unplug
the volume pedal, them power on again.
3. Refer to the Interconnect Diagram. Check the  at ribbon cable from J11 on the Engine
Board to J13 on the Interface Board.
4. Check the solder connections at the connectors.
5. Refer to the Engine Board schematics, page 7-6, and check the signal activity on the DAC,
U15.
6. Trace the signal path from the Engine Board through the Interface Board to the audio jacks.
Distortion
1. Connect headphones to the headphone jack and check the audio.
2. If there is no distortion and the audio is good, most likely the problem is a bad speaker.
3. Disconnect the speakers and reconnect them one at time to isolate the bad speaker.
4. Replace the bad speaker.
Troubleshooting & Maintenance
Power Problems
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