GEM Powerstation SK760, Service Manual

Page: 1 / 29

1 1
1 1
1
J J J J J
Index
Soldering point.
Male connector.
Female connector.
M/F faston connector.
Test point.
Supply voltage. Logic supply ground.
Analog supply ground.
Chassis ground.
Earth ground.
Flag joined with one or more flags
GENERALMUSIC S.p.A. Sales Division: 47842 S.Giovanni in Marignano (RN) ITALY - Via delle Rose, 12 - tel. 0541/959511 - fax 0541/957404
GENERALMUSIC on the NET: http://www.generalmusic.com
Opening and Keyboard Disassembling Instructions & NOTICE 2
Layout SK760
3
Block Diagram (TRF and SWT versions)
5
6
7
8
Controls Interface & Controls Panel Board (TRF) Schematics
9
10
11
12
13
14
Controls Interface & Controls Panel Board (TRF) Pcb Layout
4
15
16
SERVICE MANUAL
L
CODE: 270216
M
Warnings
with the same signal name inscribed.
Address
ATTENTION
Observe precautions when handling electrostatic sensitive devices.
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.
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.
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 1/8
Ω
unless otherwise specified.
All switches shown in the "OFF" position. All DC voltages measured to ground with a voltmeter 20KOhm/V.
Assembly & Wiring Connections SK760 (TRF version)
Timings Table
17
Assembly & Wiring Connections SK760 (SWT version)
76 Notes L/R Contact and Keyboard Interface Board Schematics
Power Supply (TRF Version), Phones and Midi & Controls I/O
Mixer Board (SWT Version) Schematic and Pcb Layout
Power Supply (TRF Version), Phones, Midi & Controls I/O and
20
Cpu & Sound Generator Map
Cpu & Sound Generator Schematic (Part 1/2)
Cpu & Sound Generator Schematic (Part 2/2)
A/V Interface Board Schematic (Optional Accessory)
Cpu & Sound Generator Pcb Layout
24
Layout SK880
Assembly & Wiring Connections SK880 (TRF version)
Assembly & Wiring Connections SK880 (SWT version)
Analog I/O Board Schematics
88 Notes L/R Contact and Keyboard Interface Board Schematics
Pcb Layouts
21
22
23
A/V Interface with Vocal Processor Board Schematic 25
A/V Interface and Vocal Processor Board Pcb Layouts
26
Test & Adjustment Procedure 27
(Optional Accessory)
18 Controls Interface & Controls Panel Board (SWT) Schematics
Controls Interface & Controls Panel Board (TRF) Pcb Layout
19
NOTE: The SK series is manufctured in two versions:
The TRF version has a traditional supply (transformer and pow-
er supply board with mixer).
The SWT version has a switching supply (switching unit and mix-
er board).
All the specifications remain the same, unless the mains voltage:
The TRF version has two nominal mains voltages 115Vac-60Hz
for U.S.A. or 230Vac-50Hz for CEE & other countries.
The SWT version accept all mains voltages into the range of
100-230Vac and 50-60Hz.
Spare Part List
28
FOURTH EDITION APRIL 2000