Read Sony HT-DDW790 / HT-DDW795 / STR-K790 Service Manual online
SERVICE MANUAL
Sony Corporation
Home Audio Division
Published by Sony Techno Create Corporation
Published by Sony Techno Create Corporation
US Model
Canadian Model
AEP Model
UK Model
FM STEREO/FM-AM RECEIVER
9-887-542-02
2007C16-1
© 2007.03
© 2007.03
Ver. 1.1 2007.03
SPECIFICATIONS
STR-K790
• STR-K790 is the tuner and the amplifier section
in HT-DDW790 and HT-DDW795.
This receiver incorporates Dolby* Digital and Pro Logic Surround and
the DTS** Digital Surround System.
*
the DTS** Digital Surround System.
*
Manufactured under license from Dolby Laboratories.
“Dolby”, “Pro Logic” and the double-D symbol are trademarks of
Dolby Laboratories.
“Dolby”, “Pro Logic” and the double-D symbol are trademarks of
Dolby Laboratories.
** “DTS” and “DTS Digital Surround” are registered trademarks of DTS,
Inc.
— Continued on next page —
AUDIO POWER
SPECIFICATIONS
SPECIFICATIONS
POWER OUTPUT AND TOTAL
HARMONIC DISTORTION:
(Models of area code US only)
HARMONIC DISTORTION:
(Models of area code US only)
With 6 ohm loads, both channels driven, from
120 – 20,000 Hz; rated 85 watts per channel
minimum RMS power, with no more than 1%
total harmonic distortion from 250 milliwatts
to rated output.
120 – 20,000 Hz; rated 85 watts per channel
minimum RMS power, with no more than 1%
total harmonic distortion from 250 milliwatts
to rated output.
Amplifier section
Power Output
1)
Stereo mode (rated) (6 ohms 1 kHz, THD 1%)
85 W + 85 W
Surround mode
2)
(reference)
(6 ohms 1 kHz, THD 10%)
RMS output
FRONT:133 W
per channel
per channel
CENTER: 133 W
SURROUND: 133 W
per channel
per channel
Surround mode
2)
(reference)
(6 ohms 100 Hz, THD 10%)
SUB WOOFER: 135 W
1)
Measured under the following conditions:
Area code
Power requirements
US, Canadian
120 V AC, 60 Hz
AEP, UK
230 V AC, 50 Hz
2)
Reference power output for front, center, surround
speakers and sub woofer. Depending on the sound
field settings and the source, there may be no
sound output.
speakers and sub woofer. Depending on the sound
field settings and the source, there may be no
sound output.
Inputs
Analog
Sensitivity: 800 mV/
50 kohms
50 kohms
Digital (Coaxial) Impedance: 75 ohms
Tone
Gain levels
±6 dB, 1 dB step
Reproduction frequency range:
28 – 20,000 Hz
FM tuner section
Tuning range
87.5 - 108.0 MHz
Antenna
FM wire antenna
Antenna terminals
75 ohms, unbalanced
Intermediate frequency
10.7 MHz
AM tuner section
Tuning range
Models of area code US, Canadian
With 10-kHz tuning scale:
530 – 1,710 kHz
4)
With 9-kHz tuning scale:
531 – 1,710 kHz
4)
Models of area code AEP, UK
With 9-kHz tuning scale:
531 – 1,602 kHz
Antenna
Loop antenna
Intermediate frequency
450 kHz
4)
You can change the AM tuning scale to 9 kHz or
10 kHz. After tuning in any AM station, turn off
the receiver. While holding down DIMMER, press
?/1. All preset stations will be erased when you
change the tuning scale. To reset the scale to 10
kHz (or 9 kHz), repeat the procedure.
the receiver. While holding down DIMMER, press
?/1. All preset stations will be erased when you
change the tuning scale. To reset the scale to 10
kHz (or 9 kHz), repeat the procedure.
General
Power requirements
Area code
Power requirements
US, Canadian
120 V AC, 60 Hz
AEP, UK
230 V AC, 50/60 Hz
2
STR-K790
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be
damaged by heat.
UNLEADED SOLDER
Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with
free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with
the lead free mark due to their particular size)
: LEAD FREE MARK
Unleaded solder has the following characteristics.
• Unleaded solder melts at a temperature about 40 °C higher
than ordinary solder.
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to
about 350
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to
about 350
°C.
Caution: The printed pattern (copper foil) may peel away if
the heated tip is applied for too long, so be careful!
• Strong viscosity
Unleaded solder is more viscou-s (sticky, less prone to flow)
than ordinary solder so use caution not to let solder bridges
occur such as on IC pins, etc.
than ordinary solder so use caution not to let solder bridges
occur such as on IC pins, etc.
• Usable with ordinary solder
It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.
also be added to ordinary solder.
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety check 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.
safety check 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 TEST
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 microamperes.).
Leakage current can be measured by any one of three methods.
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microamperes.).
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.
instruments.
2. A battery-operated AC milliammeter. The Data Precision 245
digital 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 2 V AC range are suitable. (See
Fig. A)
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 2 V AC range are suitable. (See
Fig. A)
Fig. A.
Using an AC voltmeter to check AC leakage.
1.5 k
Ω
0.15
µ
F
AC
voltmeter
(0.75 V)
voltmeter
(0.75 V)
To Exposed Metal
Parts on Set
Parts on Set
Earth Ground
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK
0
OR DOTTED LINE
WITH MARK
0
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.
REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE
PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR
IN SUPPLEMENTS PUBLISHED BY SONY.
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE
0
SUR
LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES
PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE
FONCTIONNEMENT. NE REMPLACER CES COM- POSANTS
QUE PAR DES PIÈCES SONY DONT LES NUMÉROS SONT
DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS
PUBLIÉS PAR SONY.
PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE
FONCTIONNEMENT. NE REMPLACER CES COM- POSANTS
QUE PAR DES PIÈCES SONY DONT LES NUMÉROS SONT
DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS
PUBLIÉS PAR SONY.
Power consumption
Power consumption (during standby mode)
0.3 W
Dimensions (w/h/d) (Approx.)
429
× 145 × 308 mm
(16 7/8
× 5 6/8 × 12 1/8
inches)
including projecting parts
and controls
including projecting parts
and controls
Mass (Approx.)
7.4 kg (16 lb 9 oz)
Area code
Power consumption
US
210 W
Canadian
290 VA
AEP, UK
220 W
Design and specifications are subject to
change without notice.
change without notice.
3
STR-K790
TABLE OF CONTENTS
1.
GENERAL
...................................................................
4
2.
TEST MODE
............................................................... 10
3.
ELECTRICAL ADJUSTMENT
............................. 12
4.
DIAGRAMS
................................................................. 13
4-1.
Block Diagram – MAIN Section – .................................. 14
4-2.
Block Diagram – DISPLAY/POWER Section – ............. 15
4-3.
Printed Wiring Board – DIGITAL Board (Side A) – ...... 16
4-4.
Printed Wiring Board – DIGITAL Board (Side B) – ...... 17
4-5.
Schematic Diagram – DIGITAL Board (1/5) – .............. 18
4-6.
Schematic Diagram – DIGITAL Board (2/5) – .............. 19
4-7.
Schematic Diagram – DIGITAL Board (3/5) – .............. 20
4-8.
Schematic Diagram – DIGITAL Board (4/5) – .............. 21
4-9.
Schematic Diagram – DIGITAL Board (5/5) – .............. 22
4-10. Printed Wiring Boards – HDMI SW Board,
HDMI BRIDGE Board (AEP, UK only) – ...................... 23
4-11. Schematic Diagram – HDMI SW Board,
HDMI BRIDGE Board (AEP, UK only) – ...................... 24
4-12. Printed Wiring Board – MAIN Board – ......................... 25
4-13. Printed Wiring Board – STANDBY Board – ................. 26
4-14. Schematic Diagram – MAIN Board (1/4) – ................... 27
4-15. Schematic Diagram – MAIN Board (2/4),
4-13. Printed Wiring Board – STANDBY Board – ................. 26
4-14. Schematic Diagram – MAIN Board (1/4) – ................... 27
4-15. Schematic Diagram – MAIN Board (2/4),
STANDBY Board – ......................................................... 28
4-16. Schematic Diagram – MAIN Board (3/4) – ................... 29
4-17. Schematic Diagram – MAIN Board (4/4) – ................... 30
4-18. Printed Wiring Board – DISPLAY Board – ................... 31
4-19. Schematic Diagram – DISPLAY Board – ...................... 32
4-20. Printed Wiring Boards – POWER Board, DCAC Board,
4-17. Schematic Diagram – MAIN Board (4/4) – ................... 30
4-18. Printed Wiring Board – DISPLAY Board – ................... 31
4-19. Schematic Diagram – DISPLAY Board – ...................... 32
4-20. Printed Wiring Boards – POWER Board, DCAC Board,
HEADPHONE Board – ................................................... 33
4-21. Schematic Diagram – POWER Board, DCAC Board,
HEADPHONE Board – ................................................... 34
5.
EXPLODED VIEWS
5-1.
Front Panel Section ......................................................... 42
5-2.
Chassis Section ................................................................ 43
6.
ELECTRICAL PARTS LIST
.................................. 44
About area codes
The area code of the receiver you purchased is
shown on the lower right portion of the rear panel
(see the illustration below).
shown on the lower right portion of the rear panel
(see the illustration below).
Any differences in operation, according to the area
code, are clearly indicated in the text, for example,
“Models of area code AA only”.
code, are clearly indicated in the text, for example,
“Models of area code AA only”.
FRONT
CENTER
L
R
L
R
SPEAKERS
Area code
Parts No.
MODEL IDENTIFICATION
– Rear Panel –
– Rear Panel –
Model
Part No.
US model
2-896-343-4
[]
Canadian model
2-896-343-5
[]
AEP, UK models
2-896-343-6
[]
4
STR-K790
SECTION 1
GENERAL
Front panel
Receiver
VIDEO 1 IN/
PORTABLE AUDIO IN/
AUTO CAL MIC
PHONES
INPUT SELECTOR
A.F.D.
MOVIE
MUSIC
?/1
9
q;
qf
qa
qd
1
2
3
4
7
6
5
8
qs
DIMMER
SLEEP
2CH
DISPLAY
MASTER VOLUME
AUTO CAL
Name
Function
A ?
/
1
(on/standby)
Press to turn the receiver
on or off.
on or off.
B
DIMMER
Press to adjust the
brightness of the display.
brightness of the display.
C
SLEEP
Press to activate the Sleep
Timer function and the
duration which the receiver
turns off automatically.
Timer function and the
duration which the receiver
turns off automatically.
D
2CH
Press to select 2CH
STEREO mode.
STEREO mode.
E
Display
The current status of the
selected component or a
list of selectable items
appears here.
selected component or a
list of selectable items
appears here.
F
DISPLAY
Press to select information
displayed on the display.
displayed on the display.
G
AUTO CAL
Press to activate the Auto
Calibration function.
Calibration function.
Name
Function
H
MASTER
VOLUME
VOLUME
Turn to adjust the volume
level of all speakers at the
same time.
level of all speakers at the
same time.
I
INPUT
SELECTOR
SELECTOR
Turn to select the input
source to playback.
source to playback.
J
Remote sensor
Receives signals from
remote commander.
remote commander.
K
MOVIE, MUSIC
Press to select sound fields
(MOVIE, MUSIC).
(MOVIE, MUSIC).
L
A.F.D.
Press to select A.F.D. mode.
M
PHONES jack
Connects to a headphone.
N
VIDEO 1 IN/
PORTABLE
AUDIO IN/
AUTO CAL MIC
jack
PORTABLE
AUDIO IN/
AUTO CAL MIC
jack
– Connects to the supplied
optimizer microphone for
the Auto Calibration
function.
the Auto Calibration
function.
– To connect a portable
audio such as MP3
player, etc..
player, etc..
