Sony STR-DB795 User manual

SERVICE MANUAL
FM STEREO FM/AM PECEIVER
AEP Model
UK Model
E Model
Australian Model
SPECIFICATIONS
STR-DB795
Ver 1.0 2004.10
9-879-195-01
2004J05-1
© 2004.10
Sony Corporation
Audio Group
Published by Sony Engineering Corporation
This receiver incorporates Dolby* Digital and Pro
Logic Surround and the DTS** Digital Surround
System.
*Manufactured under license from Dolby
Laboratories.
“Dolby”, “Pro Logic” and the double-D symbol are
trademarks of Dolby Laboratories.
**“DTS” and “DTS Digital Surround” are registered
trademarks of Digital Theater Systems, Inc.
– Continued on next page –
Amplifier section
POWER OUTPUT
Models of area code AEP, UK, TW, KR, AUS
Rated Power Output at Stereo Mode
(8 ohms 1 kHz, THD 0.7%)100 W + 100 W2)
90 W + 90 W3)
Reference Power Output2)
(8 ohms 20 Hz−20 kHz, THD 0.09%)
FRONT1): 90 W + 90 W
CENTER1): 90 W
SURR1): 90 W + 90 W
SURR BACK1): 90 W +
90 W
(8 ohms 1 kHz, THD 0.7%)FRONT1): 100 W + 100 W
CENTER1): 100 W
SURR1): 100 W + 100 W
SURR BACK1): 100 W +
100 W
(8 ohms 1 kHz, THD 10%)FRONT1): 110 W + 110 W
CENTER1): 110 W
SURR1): 110 W + 110 W
SURR BACK1): 110 W +
110 W
Models of area code SP, MY
Rated Power Output at Stereo Mode
(8 ohms 1 kHz, THD 0.7%)90 W + 90 W2)
Reference Power Output2)
(8 ohms 1 kHz, THD 0.7%)FRONT1): 90 W + 90 W
CENTER1): 90 W
SURR1): 90 W + 90 W
SURR BACK1): 90 W +
90 W
1) Depending on the sound field settings and the
source, there may be no sound output.
2) Measured under the following conditions:
3) Measured under the following conditions:
Area code Power requirements
AEP, UK, SP, MY, KR 230 V AC, 50 Hz
AUS 240 V AC, 50 Hz
TW 110 V AC, 60 Hz
Area code Power requirements
KR 220 V AC, 50 Hz
Frequency response
Inputs (Analog)
PHONO RIAA equalization curve
±0.5 dB
MULTI CH IN, SA-CD/
CD, MD/TAPE, DVD,
TV/SAT, VIDEO 1, 2, 3
10 Hz −100 kHz
+0.5/−2 dB (when
ANALOG DIRECT is
selected)
PHONO Sensitivity: 2.5 mV
Impedance: 50 kilohms
S/N3): 86 dB
(A, 2.5 mV4))
MULTI CH IN, SA-CD/
CD, MD/TAPE, DVD,
TV/SAT, VIDEO 1, 2, 3
Sensitivity: 150 mV
Impedance: 50 kilohms
S/N4): 96 dB
(A, 150 mV5))

2
STR-DB795
4) INPUT SHORT.
5) Weighted network, input level.
Inputs (Digital)
Outputs
EQ
FM tuner section
Tuning range 87.5 - 108.0 MHz
Antenna FM wire antenna
Antenna terminals 75 ohms, unbalanced
Intermediate frequency 10.7 MHz
Sensitivity
Mono: 18.3 dBf, 2.2 µV/75 ohms
Stereo: 38.3dBf, 22.5µV/75ohms
Useable sensitivity 11.2 dBf, 1 µV/75 ohms
S/N
Mono: 76 dB
Stereo: 70 dB
Harmonic distortion at 1 kHz
Mono: 0.3%
Stereo: 0.5%
Separation 45 dB at 1 kHz
Frequency response 30 Hz −15 kHz,
+0.5/−2 dB
Selectivity 60 dB at 400 kHz
AM tuner section
Tuning range
Models of area code AEP, UK, SP, MY, TW, KR, AUS
With 9-kHz tuning scale 531 −1,602 kHz
Antenna Loop antenna
Intermediate frequency 450 kHz
Usable sensitivity 50 dB/m (at 1,000 kHz or
999 kHz)
S/N 54 dB (at 50 mV/m)
Harmonic distortion 0.5% (50 mV/m, 400 Hz)
Selectivity
At 9 kHz: 35 dB
Video section
Inputs/Outputs
Video: 1 Vp-p, 75 ohms
S-video: Y: 1 Vp-p, 75 ohms
C: 0.286 Vp-p, 75 ohms
COMPONENT VIDEO: Y: 1 Vp-p, 75 ohms
B-Y: 0.7 Vp-p, 75 ohms
R-Y: 0.7 Vp-p, 75 ohms
80 MHz HD Pass Through
General
Power requirements
DVD (Coaxial) Impedance: 75 ohms
S/N: 100 dB
(A, 20 kHz LPF)
DVD, TV/SAT, MD,
VIDEO3 (Optical) S/N: 100 dB (A, 20 kHz LPF)
MD/TAPE (REC OUT),
VIDEO 1, 2
(AUDIO OUT)
Voltage: 150 mV
Impedance: 2.2 kilohms
SUB WOOFER Voltage: 2 V
Impedance: 1 kilohms
Gain levels ±10 dB, 1 dB step
Area code Power requirements
AEP, UK 230 V AC, 50/60 Hz
AUS 240 V AC, 50 Hz
SP, MY 220−230 V AC, 50/60 Hz
TW 110 V AC, 60 Hz
KR 220−230 V AC, 50/60 Hz
Power consumption
Power consumption (during standby mode)
0.3 W (when “POWER
SAVE” in the
CUSTOMIZE menu is set
to “ON”)
Dimensions 430 ×161 ×400 mm
including projecting parts
and controls
Mass (Approx.) 14.5 kg
Supplied accessories
FM wire antenna (1)
AM loop antenna (1)
Remote commander RM-PP413 (1)
R6 (size-AA) batteries (2)
Design and specifications are subject to change
without notice.
Area code Power consumption
AEP, UK, SP, MY, KR, AUS 270 W
TW 650 W
•Abbreviation
AUS:Australian model
KR : Korean model
MY : Malaysia model
SP : Singapore model
TW : Taiwan model

3
STR-DB795
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety check before releasing the set to the customer:
Checktheantennaterminals,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.
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-operatedAC 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-operatedACvoltmeter. The “limit” indication
is 0.75V, 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 VAC range are suitable. (See
Fig. A)
Fig. A. Using an AC voltmeter to check AC leakage.
1.5 k Ω 0.15 µ FAC
voltmete
r
(0.75 V)
To Exposed Metal
Parts on Set
Earth Ground
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.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE
WITH MARK 0ON 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.

4
STR-DB795
TABLE OF CONTENTS
7. EXPLODED VIEWS
7-1. Case Section .................................................................... 68
7-2. Chassis Section-1 ............................................................ 69
7-3. Chassis Section-2 ............................................................ 70
7-4. Main Block Section ......................................................... 71
7-5. MAIN Board Block ......................................................... 72
7-6. Chassis Section-3 ............................................................ 73
7-7. Front Panel Block-1......................................................... 74
7-8. Front Panel Block-2......................................................... 75
7-9. Front Panel Block-3......................................................... 76
8. ELECTRICAL PARTS LIST................................ 77
1. SERVICING NOTES ............................................... 5
2. GENERAL ................................................................... 7
3. DISASSEMBLY
3-1. Disassembly Flow ........................................................... 9
3-2. Case (414535).................................................................. 10
3-3. COMP-V Board............................................................... 10
3-4. Back Panel Block ............................................................ 11
3-5. Main Block ...................................................................... 11
3-6. DIGITAL Board .............................................................. 12
3-7. STAY 3/STAY 4/SP-B/SP-A/S-VIDEO/VIDEO/
VIDEO-AU/AU-IN Board............................................... 12
3-8. MAIN board .................................................................... 13
4. TEST MODE.............................................................. 14
5. ELECTRICAL ADJUSTMENTS ......................... 15
6. DIAGRAMS
6-1. Block Diagram −TUNER/VIDEO Section − ................. 17
6-2. Block Diagram −AUDIO DSP Section − ....................... 18
6-3. Block Diagram −AUDIO CONTROL Section −............ 19
6-4. Block Diagram −AUDIO AMP Section − ...................... 20
6-5. Block Diagram
−DISPLAY/KEY CONTROL Section − ........................ 21
6-6. Block Diagram −POWER SUPPLY Section −.............. 22
6-7. Printed Wiring Board
−DIGITAL Section (1/2) − ............................................. 24
6-8. Printed Wiring Board
−DIGITAL Section (2/2) − ............................................. 25
6-9. Schematic Diagram −DIGITAL Section (1/4) − ............ 26
6-10. Schematic Diagram −DIGITAL Section (2/4) − ............ 27
6-11. Schematic Diagram −DIGITAL Section (3/4) − ............ 28
6-12. Schematic Diagram −DIGITAL Section (4/4) − ............ 29
6-13. Printed Wiring Boards −VIDEO Section − .................... 30
6-14. Schematic Diagram −VIDEO Section −......................... 31
6-15. Printed Wiring Boards −S-VIDEO Section −................. 32
6-16. Schematic Diagram −S-VIDEO Section − ..................... 33
6-17. Printed Wiring Board −COMP-V Section −................... 34
6-18. Schematic Diagram −COMP-V Section − ..................... 35
6-19. Printed Wiring Board −AU-IN Section − ....................... 36
6-20. Schematic Diagram −AU-IN Section − .......................... 37
6-21. Printed Wiring Board −MAIN Section −........................ 38
6-22. Schematic Diagram −MAIN Section (1/3) − ................. 39
6-23. Schematic Diagram −MAIN Section (2/3) − ................. 40
6-24. Schematic Diagram −MAIN Section (3/3) − ................. 41
6-25. Printed Wiring Board −A CLASS Section − .................. 42
6-26. Schematic Diagram −A CLASS Section − ..................... 43
6-27. Printed Wiring Board −SBL Section −........................... 44
6-28. Schematic Diagram −SBL Section −.............................. 45
6-29. Printed Wiring Board −SP Section −.............................. 46
6-30. Schematic Diagram −SP Section − ................................ 47
6-31. Printed Wiring Boards −DISPLAY Section − ................ 48
6-32. Schematic Diagram −DISPLAY Section − .................... 49
6-33. Printed Wiring Boards −DC Section − ........................... 50
6-34. Schematic Diagram −DC Section − .............................. 51
6-35. Printed Wiring Boards −AC Section − ........................... 52
6-36. Schematic Diagram −AC Section −................................ 53

5
STR-DB795
• MODEL IDENTIFICATION
– Back Panel –
PART No.
Model PART No.
AEP and UK models 4-050-932-0[]
Singapore and Malaysia models 4-050-932-2[]
Australian model 4-050-932-3[]
Taiwan model 4-050-932-4[]
Korean model 4-050-932-5[]
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
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 °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.
•Usable with ordinary solder
It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.
SECTION 1
SERVICING NOTES

6
STR-DB795
SERVICE POSITION
[Connecting the clip for GND]
When checking without back panel, it is necessary to connect the clip for GND to a chassis.
clip
AU-IN board (JW101
)
It is necessary to remove cord bushing from back panel.

7
STR-DB795
SECTION 2
GENERAL This section is extracted from
instruction manual.
Main unit
A.F.D. qg
DIRECT q;
DISPLAY 7
Display 5
INPUT MODE 8
INPUT SELECTOR qs
IR receptor 1
MAIN MENU 3
MASTER VOLUME −/+ 9
MEMORY/ENTER 4
MENU ws
MOVIE qf
MULTICHANNELDECODING
indicator 6
MULTI CH IN qa
MUSIC qd
PHONES jack wd
PRESET TUNING −/+ ql
SPEAKERS (OFF/A/B/A+B) wf
SURR BACK DECODING qj
TUNING −/+ qk
VIDEO 3 INPUT jacks wa
ALPHABETICAL ORDER
2CH qh
−/+ w;
?/1 (power) 2
NUMBERS AND SYMBOLS
2896534 7
1
wawf wdws w; qk qj qh qg qf qd qs q;qaql
HX
Mm
.>
-
VIDEO1 VIDEO2
RM SET UP
SYSTEM STANDBY SLEEP
AV1 AV2
TV ?/1 AV ?/1
VIDEO3 DVD
TV/SAT
MD/TAPE SA-CD/CD TUNER
PHONO AUX
MULTI CH SOURCE
SHIFT
TOP MENU/
GUIDE AV MENU MUTING
MASTER
VOL
DISPLAY
TV VOL TV CH
WIDE DIMMER
TV/
VIDEO MAIN MENU
RETURN/EXIT
D.TUNING DISC ALT
ANT CLEAR SEARCH MODE
2CH A.F.D.
123
456
789
0/10 >10/11 12
MOVIE
SUBTITLE ENTER
MUSIC
AUDIO ANGLE JUMP/
TIME PRESET/ CH/D.SKIP
TEST
TONE SB DECODINGDIRECT DUAL
MONO
x
?/1
P
O
v
V
bB
1
2
9
qa
5
3
4
6
7
8
q;
qs
qd
qf
qg
qh
qj
qk
w;
ws
wd
wf
wg
wa
wh
ql
ENTER
The tables below show the settings of each
button.
Remote
Button Operations Function
A.F.D. wd Receiver Selects the decoding
mode for audio sound.
ALT 9Remote When ALT button lights
up, itchangestheremote
key function to activate
those buttons with
orange printing.
ANGLE
w;
DVD player Selects viewing angle or
changes the angles.
ANT ql VCR Selects output signal
from the antenna
terminal: TV signal or
VCR program.
AUDIO
wa
TV/VCR/
DVD player Changes the sound to Multiplex, Bilingual or
Multi channel TV
Sound.
AUX wf Receiver To listen to an audio
equipment.
AV
MENU qj
VCR/
Satellite tuner/
DVD player
Displays menu.
AV1 and
AV2 wh
Remote Selects the command
mode of the remote.
AV ?/1
1
TV/VCR/
CD player/
VCD player/
LD player/
DVD player/
MD deck/
DAT deck
Turns the audio and
video components on or
off.
CLEAR
qk
CD player/
DVD player Clears a mistake when you press the incorrect
numeric buttons or
returns to continuos
playback etc.
DIMMER
qf
Receiver Adjuststhebrightnessof
the display.
DIRECT
ws
Receiver Selects 2CH ANALOG
DIRECT.
DISC q; CD player/
VCD player Selects a disc directly (multi-disc changer
only).
Remote
Button Operations Function
DISPLAY
qg
TV/VCR/
VCD player/
LD player/
DVD player
Selects information
displayed on the TV
screen.
D.TUNING
qk
Receiver Enters direct tuning
mode.
DUAL
MONO 6
Receiver Selects the language
you want during
digital broadcast.
DVD 2Receiver To watch DVD.
ENTER 8TV/VCR/
satellite tuner/
LD player/
MD deck/
DAT deck/
Tape deck
After selecting a
channel, disc or track
using the numeric
buttons, press to enter
the value.
ENTER qh Receiver/
VCR/
Satellite tuner/
DVD player
Enters the selection.
JUMP/TIME
7
Satellite tuner Toggles between the
previous and the
current channels.
CD player/
MD deck/
VCD player/
DVD player
Shows the time or
displays the playing
time of disc, etc.
MAIN
MENU qd
Receiver Selects the menu of
the receiver.
MASTER
VOL +/−
qs
Receiver Adjusts the master
volume of the
receiver.
MD/TAPE
wg
Receiver To listen to Minidisc
or audio tape.
MOVIE 4Receiver Selects the pre-
programmed sound
fields for movie.
MULTI CH
3
Receiver Selects MULTI CH
IN source.
MUSIC 5Receiver Selects the pre-
programmed sound
fields for music.
MUTING qa Receiver Mutes the soundfrom
the receiver.
Remote Commander (RM-PP413)

8
STR-DB795
HX
Mm
.>
-
VIDEO1 VIDEO2
RM SET UP
SYSTEM STANDBY SLEEP
AV1 AV2
TV ?/1 AV ?/1
VIDEO3 DVD
TV/SAT
MD/TAPE SA-CD/CD TUNER
PHONO AUX
MULTI CH SOURCE
SHIFT
TOP MENU/
GUIDE AV MENU MUTING
MASTER
VOL
DISPLAY
TV VOL TV CH
WIDE DIMMER
TV/
VIDEO MAIN MENU
RETURN/EXIT
D.TUNING DISC ALT
ANT CLEAR SEARCH MODE
2CH A.F.D.
123
456
789
0/10 >10/11 12
MOVIE
SUBTITLE ENTER
MUSIC
AUDIO ANGLE JUMP/
TIME PRESET/ CH/D.SKIP
TEST
TONE SB DECODINGDIRECT DUAL
MONO
x
?/1
P
O
v
V
bB
wj
e;
ea
eh
es
wk
wl
eg
ed
ef
ra
rs
ej
ek
el
r;
rd
rf
rh
rg
rj
rk
rl
t;
ta
td
ts
tf
ENTER
Remote
Button Operations Function
PHONO rl Receiver To listen to turntable.
PRESET/
CH/ Receiver Selects preset stations.
D.SKIP +/−
ed TV/VCR/ satellite tuner Selects preset channels.
CD player/
VCD player/
DVD player/
MD deck
Skips discs (multi-
disc changer only).
RETURN/
EXIT ej VCD player/ LD player/
DVD player
Returns to the
previous menu.
Satellite tuner Exits the menu.
RM SET UP
tf Remote To set up the remote.
SA-CD/CD
wl Receiver To listen to Super Audio CD orcompact
disc.
SB
DECODING
es
Receiver Selects the surround
back decoding modes.
SEARCH
MODE q; DVD player Selects searching mode. Press to select
the unit for search
(track, index, etc.)
SHIFT ql Receiver Selects a memory
page for presetting
radio stations or
tuning to preset
stations.
SLEEP wj Receiver Activates the sleep
function and the
duration which the
receiver turns off
automatically.
SOURCE ea Remote Selects 2ND AV
output.
SUBTITLE
ef DVD player Changes the subtitles.
SYSTEM
STANDBY
(Press AV
?/1 1and
?/1 wj at
the same
time)
Receiver/
TV/VCR/
Satellite tuner/
CD player/
VCD player/
LD player/
DVD player/
MD deck/
DAT deck
Turns off the receiver
and other Sony audio/
video components.
TEST
TONE rj Receiver Outputs test tone.
Remote
Button Operations Function
TOP MENU/ DVD player Displays DVD title.
GUIDE rs Satellite tuner Displays guide menu.
TUNER e; Receiver To listen to radio
programs.
TV CH +/−
r;
TV Selects preset TV
channels.
TV/SAT t; Receiver To watch TV
programs or satellite
receiver.
TV/VIDEO
ek
TV Selects input signal:
TV input or video
input.
TV VOL
+/−ra
TV Adjusts the volume of
the TV.
TV ?/1 td TV Turns the TV on or
off.
VIDEO1 ta Receiver To watch VCR.
(VTR mode 3)
VIDEO2 ts Receiver To watch VCR.
(VTR mode 1)
VIDEO3 wk Receiver To watch VCR.
(VTR mode 2)
WIDE el TV Selects the wide
picture mode.
1-9 and
0/10 rh
Receiver Use with SHIFT to
preset radio station or
tuning to preset
stations and with
D.TUNING for direct
tuning.
CD player/
VCD player/
LD player/
MD deck/
DAT deck
Selects track
numbers.
0/10 selects track 10.
TV/VCR/
Satellite tuner
Selects channel
numbers.
2CH rk Receiver Selects 2CH
STEREO mode.
>10/11 ef CD player/
VCD player/
LD player/
MD deck
Selects track numbers
over 10.
-/-- q; TV Selects the channel
entrymode,eitherone
or two digit.
Remote
Button Operations Function
?/1 wj Receiver Turns the receiver on
or off.
./>
rg ef VCR/ CD player/
VCD player/
LD player/
DVD player/
MD deck/
DAT deck/
Tape deck
Skips tracks.
m/M
rf CD player/ VCD player/
DVD player
LD player/
MD deck
Searches tracks in the
forward or backward
direction.
VCR/
DAT deck/
Tape deck
Fastforwards or
rewinds.
Nrd VCR/
CD player/
VCD player/
LD player/
DVD player/
MD deck/
DAT deck/
Tape deck
Starts playback.
Xeg VCR/
CD player/
VCD player/
LD player/
DVD player/
MD deck/
DAT deck/
Tape deck
Pauses playback or
recording.(Alsostarts
recording with
components in
recording standby.)
xeh VCR/
CD player/
VCD player/
LD player/
DVD player/
MD deck/
DAT deck/
Tape deck
Stops playback.
Oej VCD player/
LD player/
DVD player
Returns to the
previous menu or
exits the menu.
V/vqh Receiver Selects a menu item.
B/bqh Receiver Adjusts or changes
the setting.
V/v/B/bqh VCR/
Satellite tuner/
DVD player
Selects a menu item.
Remote
Button Operations Function
Notes
Some functions explained in this section may not
work depending on the model.
The above explanation is intended to serve as an
example only. Therefore, depending on the
component the above operation may not be possible
or may operate differently than described.
To activate the buttons with orange printing, press
ALT first before pressing the buttons.
The SOURCE button on the remote is not available
for receiver operation.
Remote
Button Operations Function

9
STR-DB795
SET
3-2. CASE (414535)
(Page 10)
3-5. MAIN BLOCK
(Page 11)
3-8. MAIN BOARD
(Page 13)
3-6. DIGITAL BOARD
(Page 12) 3-7. STAY 3/STAY 4/SP-B/SP-A/S-VIDEO/ VIDEO/VIDEO-AU/AU-IN BOARD
(Page 12)
3-4. BACK PANEL BLOCK
(Page 11)
3-3. COMP-V BOARD
(Page 10)
SECTION 3
DISASSEMBLY
•This set can be disassembled in the order shown below.
3-1. DISASSEMBLY FLOW

10
STR-DB795
3-3. COMP-V BOARD
1 two screws
(BVTP3
× 8)
7 case (414535)
4 two screw
s
(flat head)
3 two screws
(flat head)
2 two screws
(flat head)
5
6
3 connector (CN351)
2 connector (CNP352)
4 COMP-V board
1 two screws
(BVTP3
× 8)
Note: Follow the disassembly procedure in the numerical order given.
3-2. CASE (414535)

11
STR-DB795
3-4. BACK PANEL BLOCK
3-5. MAIN BLOCK
4 wire (flat type)
(CN1103)
qd back panel block
qa eight screws
(BVTP3
× 8)
0 six screws
(BVTP3
× 8
)
9 five screws
(BV3
× 8)
8 six screws (BVTP3 × 8)
qs screw
(BVTP3
× 10)
7 three screws (BVTP3 × 8)
6 two screws (BVTP3 × 8)
5 two screws
(BVTP3
× 8)
2 connector (CN901)
3 connector (CN902)
1 connector (CN2)
7 connector
(CN909)
6 connector
(CN907)
5 connector
(CN910)
4 two connectors
(CN913, 1112)
3 connector
(CN202)
qa screw
2 connector
(CN853)
1 connector
(CN417)
9 two screws
(BVTP3
× 8)
qs main block
0 two screws
(BVTP3
× 8)
8 wire (flat type)
(CN1105)

12
STR-DB795
3-6. DIGITAL BOARD
3-7. STAY 3/STAY 4/SP-B/SP-A/S-VIDEO/VIDEO/VIDEO-AU/AU-IN BOARD
3 connector
(CN1107)
1 two connectors
(CN1110, CN1111)
2 connector
(CN1106)
5 DIGITAL board
4 two connectors
(CN402, 403)
8 SP-B board
0 SP-A board
6 STAY 4 board
3 STAY 3 board
qs S-VIDEO board
5 connector (CN451)
4 connector (CN450)
7 two connectors
(CN412, 413)
9 two connectors
(CN410, 411)
qa connector (CN408)
qg connector (CN406)
ql AU-IN board
qh VIDEO-AU board
qj harness (CN132
)
qk two connectors
(CN404, 405)
2 connector (CN447)
1 connector (CN104)
qd connector (CN407)
qf VIDEO board

13
STR-DB795
3-8. MAIN BOARD
9 heatsink block
0 MAIN board
8 twelve screws
(transistor)
2 two connectors
(CN2701, 2703)
1 six connectors (CN421, 401, 601, 651, 501, 420)
3 connector (CN951)
5 connector (CN423)
6 connector (CN416)
7 connector (CN409)
4 A CLASS board

14
STR-DB795
TUNER FACTORY PRESET MODE
All preset contents are reset to the default setting.
Procedure:
1. While pressing the [MUSIC] and [PRESET TUNING --] buttons,
press the I/1button to turn on the main power.
2. The message “FACTORY” appears and the present contents
are reset to the default values.
TUNER AM STEP CHANGE (9 kHz/10 kHz) MODE
Either the 9 kHz step or 10 kHz step can be selected for the AM
channel step.
Procedure:
1. Press the I/1button to turn on the main power.
2. Turn the [INPUT SELECTOR] dial to select the “AM”
3. Press the I/1button to turn off the main power.
4. While pressing the [PRESET TUNING +] or[TUNING +] button,
press the I/1button to turn on the main power.
5. Either the message “9 K STEP” or “10 K STEP” appears.
Select the desired step.
TUNER AUTOBETICAL TUNING MODE
(AEP and UK models)
Procedure:
1. While pressing the [MEMORY/ENTER] button, press the
I/1button to turn on the main power.
2. The message “AUTO-BETICAL SELECT” appears and scans
and stores all the FM and FM RDS stations in the broadcast
area.
3. When done, the message “FINISH” appears.
SOUND FIELD CLEAR MODE
The preset sound field is cleared when this mode is activated. Use
this mode before returning the product to clients upon completion
of repair.
Procedure:
1. While pressing the [2CH] button, press the I/1button to turn
on the main power.
2. The message “SF. CLR.” appears and initialization is
performed.
FLUORESCENT INDICATOR TUBE PATTERN
CHECK MODE
All fluorescent segments are tested. When this test is activated, all
segments turn on at the same time, then each segment turns on one
after another.
Procedure:
1. While pressing the [PRESET TUNING --] and [A.F.D.] buttons,
press the I/1button to turn on the main power.
2. All segmentsand[MULTI CHANNEL DECODING] indicator LED
turn on.
SHIPMENT MODE
All preset contents are cleared when this mode is activated. Use
this mode before returning the product to clients upon completion
of repair.
Procedure:
1. While pressing the [PRESET TUNING --] and [SURR BACK
DECODING] buttons, press the I/1buttonto turn ton the main
power.
2. The message “CLEARING” appears and memories are reset
tothe default valuesand the mainpowerturn offautomatically.
SWAP ALL MODE
Procedure:
1. While pressing the [PRESET TUNING +] and [A.F.D.] buttons,
press the I/1button to turn on the main power.
2. The message “SWAP” appears.
COMMAND MODE CHANGE MODE
The command mode of the remote-commander which this set
receives can be changed.
Procedure:
1. While pressing the [INPUT MODE] buttons, press the I/1but-
ton to turn the main power.
2. Either the message “C.MODE.AV1” or “C.MODE.AV2”
appears. Select the desired mode.
VERSION CHECK MODE
The version of the micro computer displayed.
Procedure:
1. While pressing the [PRESET TUNING --] and [2CH] buttons,
press the I/1button to turn the main power.
2. The version of the micro computer and model destination are
displayed.
DECODE AUTO ALL MODE
Procedure:
1. While pressing the[PRESET TUNING --] and [MOVIE] buttons,
press the I/1button to turn the main power.
2. The message “DEC TEST” appears.
PROTECTOR AUTO OFF
When this mode is used, a protector on state is maintainable.
Procedure:
1. While pressing the [PRESET TUNING +] and [MOVIE] buttons,
press the I/1button to turn on the main power.
2. The message “PROT EVER” appears.
SECTION 4
TEST MODE

15
STR-DB795
BIAS ADJUSTMENT
Condition:
input signal: no signal (no load)
volume: minimum
Connection
Procedure:
1. Connect a digital voltmeter to the CN432 (CN482, CN532,
CN582, CN632, CN682) on the MAIN board or CN732 on
the SBL board.
2. Press the I/1button to turn on the main power.
3. Adjust the RV431 (RV481, RV531, RV581, RV631, RV681)
on the MAIN board or RV731 on the SBL board so that the
digital voltmeter reading is 15±2 mV.
Note: When the adjusting voltage is higher than 15±2 mV, adjust the
voltage to the minimum voltage.
Adjustment and Connection Loacation:
+
–
digital voltmeter
CN432 (CN482, 532, 582, 632, 682, 732) pin
1
CN432 (CN482, 532, 582, 632, 682, 732) pin 2
RV731
– SBL BOARD (Component Side) –
CN732 1
2
–MAIN BOARD (Component Side) –
RV431 CN432
2 1
RV481 RV631 RV681 RV531 RV581
CN482
CN632 CN682
CN532
CN582
2 1 2 1 2 1 2 1 2 1
SECTION 5
ELECTRICAL ADJUSTMENTS

16
STR-DB795
MEMO

STR-DB795
1717
STR-DB795
6-1. BLOCK DIAGRAM –TUNER/VIDEO Section –
SECTION 6
DIAGRAMS
• SIGNAL PATH
: TUNER
A
DATA,
CLK
FM
AM
8L CH
10R CH
13FM SIG OUT
14RDS-INT
15RDS-DATA
116VIDEO_SW3
117VIDEO_SW4
115VIDEO_SW2
114VIDEO_SW1
100UP CON SCL
99UP CON SDA
2
ST-DO
4
CE
3ST-DI
1CLK
7
STEREO
11
MUTE
6
TUNED
(AEP, UK)
TU301
TUNER UNIT
47 RDS.DATA
RDS_SIGNAL
RDS_CLK
66 TUNER LATCH
49 TUNER TUNED
48 TUNER ST
50 TUNER MUTE
135
65 TUNER DO
61
SYSTEM CONTROLLER
IC1703 (1/6)
B
TUNER-L
COAXIAL
FM 75
AM
R-CH
: VIDEO
ANTENNA
SW4
SW3
SW2
SW1
7
9
3
5
13
V3
V2. IN
TV
LD
V1. IN
10
4
14
6
2
15
1
SW2
SW3
SW1
SW4
SW5
V1.
OUT
M.
OUT
7
9
3
5
13
V3
V2. IN
TV
LD
V1. IN
10
4
14
6
2
15
1
SW2
SW3
SW1
SW4
SW5
V1.
OUT
M.
OUT
15
13
9
11
3
5
7
1
2
14
10
4
6
D302
D301
D851
D850
J1091 (1/2)
VIDEO 3
INPUT
VIDEO
TV/SAT IN
DVD IN
VIDEO 2 IN
VIDEO 2 OUT
J305
J304
VIDEO
VIDEO VIDEO
VIDEO 1 IN
VIDEO 1 OUT
J1092
J852 (2/2)
J850 (2/2)
J850 (1/2)
J852 (1/2)
C
Y
C
Y
C
Y
C
Y
C
Y
J302
VIDEO SELECTOR
IC301
Y SWITCH
IC851
C SWITCH
IC850
VIDEO 3
INPUT
S-VIDEO
S-VIDEO
TV/SAT IN
S-VIDEO
DVD IN
S-VIDEO
VIDEO 1 IN
VIDEO
MONITOR OUT
V1. OUT
V1. IN
V2. IN
V2. OUT
TV
LD
V3
M. OUT
SW5
SW1
SW2
SW3
SW4
S-VIDEO
VIDEO 1 OUT
SW4 SW1 SW2 SW3
P B /C B /B-Y
P R /C R /R-Y
P B /C B /B-Y
P R /C R /R-Y
J351 (1/2)
Y
Y
J351(2/2)
Y
COMPONENT
VIDEO
TV/SAT IN
COMPONENT
VIDEO
DVD IN
P B /C B /B-Y
P R /C R /R-Y
COMPONENT
VIDEO
MONITOR OUT
C
YJ851
S-VIDEO
MONITOR OUT
RY850
-2
-1
VIDEO BUFFER
Q372
19
27
7
15 16
25
VIDEO SYNC
SEPARATOR
IC370
4
1
7
16
CLOCK
GENERATOR
IC371
X370
3.5795MHz (Taiwan, Korean models)
4.43MHz (EXCEPT Taiwan, Korean models)
C SYNC BUFFER
Q370
RELAY
DRIVE
Q850, 851
SYNC SEPARATOR
IC852
Y SYNC BUFFER
Q371
RY352
-2
-1
RY354
RELAY
DRIVE
Q352
RY351
-2
-1
RY353
RELAY
DRIVE
Q351
VIDEO AMP
IC372
DATA
CLK
• R-CH is omitted due to same as L-CH.
(Page 21)
(Page 19)

STR-DB795
1818
STR-DB795
6-2. BLOCK DIAGRAM – AUDIO DSP Section –
: AUDIO (ANALOG)
: AUDIO (DIGITAL)
VIDEO
ANALOG
F
BCKO,
LRCKO
G
S MUTE
H
SCLKO
LRCKO
BCKO
4
DIGITAL
CONTROL
DATA
DEMODULATOR
LOCK
DETECT
TIMING
MICON INTERFACE
CLOCK
INPUT
CIRCUIT
IC1102
IC1151
J1101
J202
VIDEO 2 OUT
DVD IN
TV/SAT IN
L
L
L
VIDEO 2 IN
J1091 (2/2)
L
J201
L
L
L
DIGITAL AUDIO INTERFACE RECEIVER
IC1101
CLK LAT DATA
VIDEO SELECTOR
IC201
4
5
7
8
3
2
10
12
1415 16
6
5
14 2
3 7
36 38 37 35
47
CKSEK1 DI CE CLK DO
48
CKSEL1
B A
DI CLK CE DO XMODE
XMODE
3DIN0 16
DATAO
34
ERROR
14
BCK
15
LRCK
17
XSTATE
21
XOUT
22
XIN
24
AUDIO
X1101
12.288MHz
D1601
HDIN
HCLK
67
DIR ERROR ANALOG_DIGITAL
121
104103
69 OPT SEL2
91 ADC:RST
70 OPT SEL1
74 CKSEL1
79 DI
75 CLK
76 CE
80 DO
73 XMODE
90
DSP_HACN
107
PM
89
DSP_HCS
102
HDOUT
88
DSP GP9
105
GP12
72
DATA0
71
XSTATE
A
B
CKSEL1
DI
CLK
CE
DO
XMODE
SYSTEM CONTROLLER
IC1703 (2/6)
18 SDI1
30 SDI2
SDCLK
69
GP8
68
GP9
36
HCS
34
HCLK
33
HDIN
35
HDOUT
32
HACN
113
PM
106
XRST
2
XRST
22
KFSIO
37
AUDIO DIGITAL
SIGNAL PROCESSOR
IC1201
23SDO1
24SDO2
25SDO3
19LRCKO
20BCKO
• SIGNAL PATH
• R-CH is omitted due to same as L-CH.
AB
VIDEO 1 IN
VIDEO 1 OUT
VIDEO 3
INPUT
AUDIO
DIGITAL OPTICAL
RECEIVER
IC1104
DIGITAL OPTICAL
RECEIVER
IC1105
DIGITAL OPTICAL
RECEIVER
IC1106
OPTICAL
DVD IN
COAXIAL IN
DVD
COAXIAL IN
SA-CD/CD
DIGITAL OPTICAL
RECEIVER
IC1081
VIDEO 3
INPUT
DIGITAL
OPTICAL
OPTICAL
TV/SAT IN
OPTICAL
MD IN
OPTICAL
MD OUT
DIGITAL OPTICAL
TRANSCEIVER
IC1107
DIGITAL SELECTOR
IC1103
28 LRCKI2
15 LRCKI1
29 BCKI2
17 BCKI1
59 EXLOCK
MUTING
SWITCH
Q1602
MUTING
SWITCH
Q1601, 1603
4DIN1
5DIN2
2DOUT
9
MCLK1
12
MCLK2
X1201
13.9MHz
EEPROM
IC1604
5112
6111
SDA
SCL
EEPROM SDA
EEPROM SCL
58
X0
57
X1
X1601
16.5MHz
108, 107, 105 – 102,
99, 98, 80 – 77,
75 – 72
112, 110, 109,
97 – 92, 82 – 85,
66 – 64
7 – 10, 13 – 16,
29 – 32, 35 – 38
5 – 1, 44 – 42,
27 – 24, 21 – 18
S-RAM
IC1202
617
CS WE
4445
CSO
WEO
D0 – D15 A0 – A15
D0 – D15 A0 – A15
67GP10
SIGNAL-END
DEFERENTIAL
CONVERTER
DIGITAL
MODULATOR
SERIAL I/O
INTERFACE
CLOCK/
TIMING CONTROL RESET
/POWER CONTROL
A/D CONVERTER
IC1401
15
14
BCK
16
SYSCLK
1DOUT
LIN
6
RSTB
13
LRCK
BUFFER
IC1402
20
XMCK
CDATA, CLK, LAT
82
LRCK SW
85
DSP_BST
56
BST
6
2
5
1
SIGNAL
SELECTOR
IC1204
D1101
SDO3
E
SDO1, SDO2,
SDO3, SDO4
D
SOURCE-L
SDO2
26SDO4 SDO4
SDO1
SWITCHING
IC1503
13
CKOUT
(Page 21)
(Page 19)
(Page 19)
(Page 19)
(Page 19)
(Page 19)

STR-DB795
1919
STR-DB795
6-3. BLOCK DIAGRAM – AUDIO CONTROL Section –
BUFFER
IC602 (2/2)
+
MODE CONTROL
INTERFACE
SERIAL INPUT
INTERFACE
MULT-FUNCTION
X8 OVER SAMPLING
DIGITAL FILTER
D/A
CONVERTER
LPF
AMP
LPF
AMP
LPF
AMP
LPF
AMP
MUTING
Q751
MUTING
Q601
MUTING
Q501
MUTING
Q401
MUTING
Q701
E
SDO1,
SDO2,
SDO3,
SDO4
F
BCKO,
LRCKO
G
S MUTE
TRIM
LEVEL SHIFT
CIRCUIT
CENTER
SUB WOOFER
P
DATA, CLK, LAT
DATA, CLK, LAT
J
FL
LEVEL SHIFT
CIRCUIT
L
SL
M
SBL
N
SB (R)
R
SW
LEVEL SHIFT
CIRCUIT
K
C
J101
45
46
47
40
41
DATA1
DATA2
DATA3
BCK
LRCK
BCKO
LRCKO
SCKI
SDO1
SDO3
SDO2
SDO4
SDO2
SDO4
34
MDI
35
MC
36
ML
37
RST
33
MDO
ML RST MDO
14
10
12
11
VOUT1
VOUT5
VOUT3
VOUT4
2 DATA
3 LRK
16 SCK
15
ML
14
MC
13
MD
7VO L
D/A
CONVERTER
IC1502
LRCKO 1 BCK
BCKO
AUDIO SELECTOR
IC101
9 5.1FL
12 5.1SL
28 5.1 C
15 5.1SW
2 PHONO
3 MD IN
4 MD OUT
5CD
24COUT
11
FLOUT
19SWOUT
10
13 D/ASL
14SLOUT
22
DATA
21
CLK
23
LAT
26 D/A C
17 D/ASW
20 VRIN 23
OUT
25
24
TRIM
13
CLK
17
LAT
16
DATA
CLK LAT DATA CLK LAT DATA
20 VRIN 23
OUT
25
TRIM
24
TRIM
13
CLK
17
LAT
16
DATA
9VRIN 6
OUT
4
TRIM
5
TRIM
CLK LAT DATA
13
CLK
17
LAT
16
DATA
CLK LAT DATA
20 VRIN 23
25
24
OUT
TRIM
TRIM
108 DA1DO
93 DA1LAT
92 DAC_RST
95 DAC_MDI
94 DACCLK
96 DA2LAT
81 GROUP SW
MDO
ML
RST
MDI
MCI
6CTR/SW RY
SYSTEM CONTROLLER
IC1703 (3/6)
DATA CLK LAT
MDI
MCI
FRONT L
SURR L
B
TUNER-L
H
SCLKO
6 TUNER
D
SOURCE-L 7 A/D, V
8 2CH
BUFFER
IC1521
BUFFER
IC1561
BUFFER
IC1541 (1/2)
BUFFER
IC1541 (2/2)
9
VOUT6
13
VOUT2
R-CH
R-CH
D/AFL
LINE AMP
IC1581 (2/2)
MUTING
Q651
8VO R LINE AMP
IC1581 (1/2)
BUFFER
IC602 (1/2)
BUFFER
IC502
ELECTRICAL
VOLUME
IC401
AUDIO SELECTOR
IC173
ELECTRICAL
VOLUME
IC601
BUFFER
IC652 (2/2)
LEVEL SHIFT
CIRCUIT
20 VRIN 23
OUT
25
TRIM
24
TRIM
13
CLK
17
LAT
16
DATA
9VRIN 6
OUT
4
TRIM
5
TRIM
CLK LAT DATA
BUFFER
IC652 (1/2)
ELECTRICAL
VOLUME
IC651
ELECTRICAL
VOLUME
IC501
D/A CONVERTER
IC1501
LINE AMP
IC112
LINE AMP
IC111 (1/2)
LINE AMP
IC111 (2/2)
22
27
26 25
19
2117
23
BUFFER
IC171
LINE AMP
IC110
CONTROL
1415 16
6
25
DATA
SELECTOR
IC1504
1
38
J151
PHONO IN L
L
SA-CD/CD IN
J131
MD/TAPE IN L
L
MD/TAPE OUT
PHONO
EQ AMP
IC131
BUFFER
IC402
J203
SUB WOOFER
RY807
Q
RELAY
DRIVE
Q826
• SIGNAL PATH
• R-CH is omitted due to same as L-CH.
: TUNER
: AUDIO (ANALOG)
: AUDIO (DIGITAL)
MUTING
CONTROL
Q813
ANALOG
MULTI CH IN
ANALOG
(Page 17)
(Page 18)
(Page 18)
(Page 18)
(Page 18)
(Page 18)
(Page 20)
(Page 20)
(Page 20)
(Page 20)
(Page 20)
(Page 20)
(Page 21)
(Page 21)

STR-DB795
2020
STR-DB795
6-4. BLOCK DIAGRAM – AUDIO AMP Section –
: AUDIO (ANALOG)
TM449 (2/2)
+
+
–
–
TM444
BIAS
Q431, 434
BOOSTER
Q402
BOOSTER
Q403
J
FL
SYSTEM CONTROLLER
IC1703(4/6)
CURRENT
DETECT
Q432, 433
CURRENT
DETECT
Q632, 633
CURRENT
DETECT
Q732, 733
5
41
134
3
2
7
118
SURR.RY
HP DETECT
LIMITTER.IN
SP.A.RY
4SP B RY
H/P RY
SB.RY
PROTECTOR
RELAY
DRIVE
Q823
RY806
R-CH
RELAY
DRIVE
Q809
RY449
RELAY
DRIVE
Q811
RY699
RELAY
DRIVE
Q807
RY549
D820
D818
PHONES
CENTER
L
R
J1086
+
+
–
–
TM699
–
–
+
+
R-CH
R-CH
SURR
L
R
SURR
BACK
L
R
RY649
D812D819D816
AF POWER
PROTECTOR
Q802, 803,
Q805
–1
RELAY
DRIVE
Q808
RY444
L
R
+
+
–
–
TM449 (1/2)
R-CH
FRONT A
FRONT B
RV431
BIAS
PRE DRIVE
Q2001, 2003
BIAS
Q2004, 2005
BIAS
Q2006
BIAS
Q531, 534
BOOSTER
Q502
BOOSTER
Q503
L
SL
RV531
BIAS
PRE DRIVE
Q2401, 2403
BIAS
Q2404, 2405
BIAS
Q2406
BIAS
Q631, 634
BOOSTER
Q602
BOOSTER
Q603
K
C
RV631
BIAS
PRE DRIVE
Q2201, 2203
BIAS
Q2204, 2205
BIAS
Q2206
BIAS
Q731, 734
BOOSTER
Q702
BOOSTER
Q703
M
SBL
RV731
BIAS
PRE DRIVE
Q2701, 2703
BIAS
Q2704, 2705
BIAS
Q2706
+
–
–2
BIAS
Q681, 684
BOOSTER
Q652
BOOSTER
Q653
N
SB (R)
RV681
BIAS
PRE DRIVE
Q2301, 2303
BIAS
Q2304, 2305
BIAS
Q2306
D411
D611
D711
CURRENT
DETECT
Q682, 683
D661
D511
R
SW
• SIGNAL PATH
• R-CH is omitted due to same as L-CH.
CURRENT
DETECT
Q532, 533
SPEAKERS
IMPEDANCE
USE 4-16Ω
+OVER VOLTAGE
DETECT
Q822
B+
(Page 19)
(Page 19)
(Page 19)
(Page 19)
(Page 19)
(Page 19)