Mystery MMD-888 Service Manual
R
PLL SYNTHESIZER STEREO RADIO WITH
DVD/VCD/MP3/CD PLAYER DIGITAL
MODE:MMD-888
CONTENTS
Page
Disassembly Instructions....................................................................................................3
Disassembly Diagram.........................................................................................................4
Operation Check................................................................................................................5
Block Diagram................................................................................................................ 6...
Alignment Locations...........................................................................................................7
Alignment Procedures........................................................................................................8
PrintedCircuit Boards.........................................................................................................9
Exploded Views (Panel)......................................................................................................15
Exploded ViewParts Lists (Panel).......................................................................................16
Exploded Views (Cabinet)..................................................................................................17
Exploded View Parts Lists(Cabinet).................................................................................... 18
Schematic Diagram............................................................................................................19
Electrical Parts List............................................................................................................25
Specifications....................................................................................................................29
2
DISASSEMBLY INSTRUCTIONS
1. Using the unlock key that came with the unit or a similar tool, unlock the Mounting Box and remove
toward the read of the unit.
2. Remove two screws (A) located on the rear of the top cabinet then remove the Top Cabinet.
3. Remove two screw (B) located on the rear of the bottom cabinet then remove the Bottom Cabint.
4. Remove two screw (C) and (D) from the side bracket of the right side.
Remove the screw (E) and (F) from the side bracket of the left side.
5. Remove two screws (G) from the base of the front side then remove the two screws (H) loated unit
the front desk bracket then remove the Front Dect Bracket.
Remove two screws (I) located under the rear deck bracket then remove the Rear Deck Bracket.
6. Remove two screws (J) from the Heat Sink then remove the Spring Sheet.
7. Remove five screws (K) from the Heat Sink then remove the Heat Sink.
8. Remove two screws (L) located on the side bracket of the rear side then remove the ISO Antenna
Socket/Shore W/Holder.
9. Remove the screw (M) located on the side bracket of the rear side.
Remove two screws (N) located on the main board then remove the HeatSink (7809/DB435).
10. Remove the screw (O) located on the side bracket of the rear side then remove the 22PIN socket.
11. Take out the Panel and the Ring.
Remove two screws (P) from each side of the base then remove the Base.
12. Remove the screw (Q) located under the main board then remove the Main Board.
3
DISASSEMBLY DIAGRAM
4
OPERATION CHECK
GENERAL SPECIFICATIONS OF SIGNAL
Frequency range
OIRT
Intermediate frequency
Practicality neat(S/N 30dB)
Practicality neat(S/N 20dB)
Frequency Character
Signal/Noise Ratio
Channel
Power
FM
AM
FM 65-74MHz
FM
AM
FM Less than 22dB
AM
87.5, 108 MHz
522-1620 KHz
10.7 MHz
450 kHz
Less than 48dB
5-20,000Hz (+2dB)
70dB(1KHz)(1EC-A Network)
2 channels (stereo)
12-13.8V, -earth
The signal strength read in this section is voltage on the antenna.
Test Diagram
ANTENNA
SIDE BRAKE
B+ 12V
BACK CAMERA
VIDEO CONTROL
L(White)
AUX LINE INPUT
R(Red)
SUBWOOFER
(Green)
L(White)
RCALINE OUTPUT
R(Red)
VIDEO INPUT
(Yellow)
VIDEO OUTPUT
(Yellow)
Brown
Brown/white
Black
Black
Green
Brown
Brown
Yellow
Black
POWER
ANTENNA
AMPLIFIER
CONTROL
ACC +
FRONT
L SP
REAR
L SP
Blue
Blue/White
Red
+
White
-
White/Black
+
Green
-
Green/Black
Pink
DIMMER CONTROL
10A
Grey
Grey/Black
Purple
Purple/Black
UNIT
Yellow B+
Black B-
+
FRONT
R SP
-
+
REAR
R SP
-
-
+
5
BLOCK DIAGRAM
6
FM/MW/LW TUNER
ALIGNMENT LOCATIONS
7
ALIGNMENT PROCEDURES
FM ADJUSTMENT
Equipment Required
AM IF/RF signal generator
Solid-state voltmeter (SSVM)
Regulated DC power supply
2-CH voltmeter
Distortion meter
FM Alignment Using FM Signal Generator
Note: Press the radio power switch to on the radio. Signal generator output must be kept as low as
possible to avoid overload and clipping.
Step
Stereo
separation
FM SNC
Adjustment
Stop
SENS.
Note: The tuner module is well-adjustand adjustemnt is not recommended.
Generator
coupling
Signal
Generator
to antenna
receptacle
98.1MHz
Dev. 75 khz
L+R=90%
Int. 1 khz
60dBuV output
Signal Generator
To antenna
receptale
Generator
98.1MHz
Int. 1 khz
Dev. 75 khz
L+R = 90 %
Pilot = 10 %
@
98.1 Mhz
Mod. 1kHZ
Dev 75kHz
Display
setting
98.1MHz
98.1MHz
98.1MHz
Adjustment Remarks
VR1
VR2
VR3
Adjust AF
output power
at maximum
separating
more than 30 dB
Stereo Separation
25 dB (+5dB)
Adjust AF to
stop station.
8
MAIN BOARD
PRINTED CIRCUIT BOARDS
TOP VIEW
9
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