-- 1 --
US Model
Canadian Model
E Model
Tourist Model
SPECIFICATIONS
FM STEREO/FM-AM TIMER TUNER
MICROFILM
ST-M9
ST-M9 is the tuner section
in DHC-MD7.
SERVICE MANUAL
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SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, "metallized" knobs, screws,
and all other exposed metal parts for AC leakage. Check leakage as
described below.
LEAKAGE
The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microampers).
Leakage current can be measured by any one of three methods.
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers' instructions to use these
instruments.
2. A battery-operated AC milliammeter. The Data Precision 245 digi-
tal multimeter is suitable for this job.
3. Measuring the voltage drop across a resistor by means of a VOM
or battery-operated AC voltmeter. The "limit" indication is 0.75
V, so analog meters must have an accurate low-voltage scale. The
Simpson 250 and Sanwa SH-63Trd are examples of a passive VOM
that is suitable. Nearly all battery operated digital multimeters
that have a 2V AC range are suitable. (See Fig. A)
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE
!
SUR LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE
DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE
FONCTIONNEMENT. NE REMPLACER CES COMPOSANTS
QUE PAR DES PIÈCES SONY DONT LES NUMÉROS
SONT DONNÉS DANS CE MANUEL OU DANS LES
SUPPLÉMENTS PUBLIÉS PAR SONY.
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 PUBLISHED BY SONY.
TABLE OF CONTENTS
1. SERVICING NOTE ...................................................... 3
2. GENERAL .................................................................... 5
3. ELECTRICAL ADJUSTMENT .................................. 7
4. DIAGRAMS
4-1.
IC Pin Function
· IC201 System Control (
µPD78013GC-652-AB8) ........... 8
4-2.
IC Block Diagrams -- Main Section -- .......................... 10
4-3.
Printed Wiring Board -- Main Section -- ....................... 11
4-4.
Schematic Diagram -- Main Section -- .......................... 13
4-5.
Schematic Diagram -- Panel Section -- .......................... 16
4-6.
Printed Wiring Board -- Panel Section -- ....................... 16
5. EXPLODED VIEW ..................................................... 19
6. ELECTRICAL PARTS LIST .................................... 20
Fig. A. Using an AC voltmeter to check AC leakage.
To Exposed Metal
Parts on Set
0.15
µF
1.5k
AC
voltmeter
(0.75V)
Earth Ground
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Power Supply During Servicing
This unit is not able to operate on its own because it does not have its own power supply. During servicing, connect to other units.
Power is supplied when the SYSTEM POWER button of the amplifier (TA-M7) is turned ON.
If the other units are not available, use a service box (PFJ-1) and jig (J-2501-078-A).
In this case, press the ENTER/NEXT button, SLEEP button simultaneously to turn on the power.
[Connection Diagram]
SERVICE BOX (PFJ-1)
POWER SW
JIG
(J-2501-078-A)
CN904
17P
CN902
7P
CORD WITH CONNECTOR 17P
(Provided with PFJ-1)
CORD WITH CONNECTOR 7P
(Provided with unit)
FH-E939, 838, 937
CDP/TC
SECTION 1
SERVICING NOTE
CN101 7P
SYSTEM CONTROL
MODEL IDENTIFICATION
-- MAIN BOARD --
IC201
JW203
JW202
JW201
CN102
FRONT PANEL
MAIN BOARD
US, Canadian
model
Tourist model
Hong Kong,
Singapore model
JW201
JW202
JW203
Mount
No Mount
Mount
Mount
No Mount
No Mount
No Mount
Mount
Mount
UNIT (ST-M9)
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KEY/Fluorescent indicator tube/LED Check Mode
To enter KEY/Fluorescent indicator tube/LED check mode, press the ENTER/NEXT and REC buttons at the same time.
Under mode, every time when press any key or turn MULTI CONTROLLER knob, change to next situation.
1 All LED indicators light on
2 All Fluorescent indicator tube indicators light on
3 A part of Fluorescent indicator tube light on mode 1. (Indicated ST-SEG)
4 A part of Fluorescent indicator tube light on mode 2. (Indicated RDS-SEG)
5 KEY check mode
NOTE :
1) All LED light on mode is keeped, when buttons which is pressed to enter all LED light on mode, release same time.
When release them separate timing, it is moved to next All LED light on mode.
2) After all LED light on mode, light on point remove one by one, when any button pressed or MULTI CONTROLLER knob turned.
3) Under KEY check mode, every time buttons pressed numerical value of "KEY" in Fluorescent indicator tube increse.
And that time, numerical value of "ECDR" increse when MULTI CONTROLLER button turn to + direction, and it decrese turn to
direction.
When you want to finish this mode, unplug the power of amplifier or turn off PFJ-1 of POWER switch.
Switching the Channel Step 9 kHz/10 kHz
1. Turn off the power of the unit.
2. While pressing the ENTER/NEXT button, press the SYSTEM POWER button of the amplifier section to turn on the power.
The value switches between 9 kHz and 10 kHz steps each time the above is carried out.
NOTE:
1) Take note not to switch the above when not required.
2) This switching cannot be performed when power is supplied using service box (PFJ-1).
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SECTION 2
GENERAL
This section is extracted from
instruction manual.