General Music SK76 Service Manual

SERVICE MANUAL
Schematic Diagrams
Power Amp. & Supply, Keyboard Interface, A/V Interface and A/V & Harmonizer Pcb Layouts
GENERALMUSIC S.p.A. Sales Division: 47048 S.Giovanni in Marignano (RN) ITALY - Via delle Rose, 12 - tel. 0541/959511 - tlx 550555 GMUSIC I - fax 0541/957404
For a correct operation of the instrument, after having switched off, be careful to wait at least 3 seconds before switching on again.
To improve the device's specifications, the schematic diagrams may be subject to change without prior notice.
Schematic Notes
All components marked by this symbol have special safety characteristics, when replacing any of these components use only
manufacturer's specified parts.
The (µ) micro symbol of capacitance value is substituted by U. The (Ω) omega symbol of resistance value is substituted by E.
The electrolytic capacitors are 25Vdc rated voltage unless otherwise specified. All resistors are 1/8W unless otherwise specified.
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Opening & Keyboard Disassembling Instructions
Block Diagram, Controls & Midi I/O and Analog I/O Pcb Layouts
Power Amp. & Supply, Midi & Controls I/O and Analog I/O Schematics, Adjustment Table
SK76 - Keyboard Interface & 76 Note L/R Contacts Schematics
SK88 - Keyboard Interface & 88 Note L/R Contacts Schematics
Controls Panel, Pitch/Modulation & Dc-Ac Converter Schematics
Keyboard and Controls Panel Interfaces Pcb Layout & Controls Panel Reverse Pcb Layout
Cpu & Sound Generator Schematic (Part 1/2)
Cpu & Sound Generator Schematic (Part 2/2)
Notice
Service must be carried out by qualified personnel only.Any tampering carried out by unqualified personnel during the guarantee
period will forfeit the right to guarantee.
Soldering point. Supply voltage.
Male connector. Logic supply ground.
Female connector. Analog supply ground.
M/F faston connector. Chassis ground.
Test point. Earth ground.
Flag joined with one or more flags with the same signal name inscribed.
Index & Warnings
SK76 - Assembly & Wiring Connections
SK88 - Assembly & Wiring Connections
Cpu & Sound Generator Pcb Layout
Timing Table
Audio/Video Interface Schematic
Audio/Video & Harmonizer Schematic
Optional Accessories Mounting Instructions
Spare Part List
ATTENTION
Observe precautions when handling
electrostatic sensitive devices
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