MICROFILM
SERVICE MANUAL
FM/MW/LW MINIDISC PLAYER
AEP Model
SPECIFICATIONS
MDX-C7890R
Model Name Using Similar Mechanism
MDX-C7900R
Base Mechanism Type
MG-164KT-138
Optical Pick-Up Name
KMS-241A/J2N
2
1.
SERVICING NOTES ................................................ 2
2.
GENERAL ................................................................... 3
3.
DISASSEMBLY ......................................................... 9
4.
ELECTRICAL ADJUSTMENTS
Test Mode ........................................................................ 14
MD Section ..................................................................... 14
Tuner Section .................................................................. 14
Flexible Circuit Board Repairing
· Keep the temperature of the soldering iron around 270 °C dur-
ing repairing.
· Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
· Be careful not to apply force on the conductor when soldering
or unsoldering.
Notes on chip component replacement
· Never reuse a disconnected chip component.
· Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
CAUTION
Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous ra-
diation exposure.
3-023-589-01 (AEP: TYPE 2)
3-023-590-01 (AEP: TYPE 1)
S
®
MDX-C7890R
MODEL NO.
FM/MW/LW MINIDISC PLAYER
POWER SELECT SWITCH
C E
A
· TYPE A/B Discrimination
[MAIN BOARD] (Component Side)
· Model Identification
Model Number Label
IC700
MB90574PFV-G-113-BND ( TYPE A )
MB90F574PFV-G-113 ( TYPE B )
Laser Diode Properites
· Material: GaAlAs
· Wavelength: 780 nm
· Emission Duration: continuous
· Laser Output Power: less than 44.6 µW*
* This output is the value measured at a distance of 200 mm
from the objective lens surface on the Optical Pick-up Block.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK ! OR DOTTED
LINE WITH MARK ! ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFE
OPERATION. REPLACE THESE COMPONENTS WITH
SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.
SECTION 1
SERVICING NOTES
5.
DIAGRAMS
5-1. Printed Wiring Boards
MECHANISM DECK Section ................................. 17
5-2. Schematic Diagram
MECHANISM DECK Section ................................. 19
5-3. Schematic Diagram MAIN Section .......................... 23
5-4. Printed Wiring Board MAIN Section ...................... 27
5-5. Printed Wiring Board PANEL Section .................... 31
5-6. Schematic Diagram PANEL Section ....................... 33
5-5. IC Pin Function Description ........................................... 35
7.
EXPLODED VIEWS ................................................ 52
8.
ELECTRICAL PARTS LIST ............................... 56
TABLE OF CONTENTS
3
SECTION 2
GENERAL
This section is extracted from
instruction manual.
4
5