Philips VR750 User manual

Service Manual
Service
Service
Service
Video Cassette Recorder
Contents
Chapter
Adjustment Procedure
Schematic Diagrams and CBA's
Exploded Views
Mechanical and Electrical Parts Lists
Sec. 1:
Sec. 2: Standard Maintenance
Mechanism Alignment Procedures
Disassembly / Assembly of Mechanism
Deck Exploded Views
Safety regulations require that the set be restored to its original
condition and that parts which are identical with those specified
be used.
Published by BK 2004 Video Service Department Printed in the Netherlands cCopyright reserved Subject to modification GB 3103 785 22280
Survey of versions:
/02 PAL B/G
/07 PAL I, UK/IRELAND
/16 PAL B/G, Spain
/39 PAL/SECAM-BG+PAL/SECAM-L/L',FRANCE
/58 PAL-BG/DK+SECAM-BG/DK,EAST-EURO
VR750/02,07,16,58
VR752/07,16,58
For technical data reference is made to the Service Manual of VR550/02/07/16
3103 785 22260. The present manual states only the differences.

1-5-3 HG490IB
OPERATING CONTROLS AND FUNCTIONS
[ VR750/ (02, 16), VR752/16 ]
Buttons for VCR feature only
To record the TV channel selected at this moment.
To switch off or on, interrupt menu function.
Press to select channels at VCR.
To select the programme number. During normal
or slow motion playback, press to adjust the tracking.
To access or remove the VCR’s on-screen
status display. To exit on-screen menus.
To delete last entry. To clear a programmed
recording (TIMER). To reset the elapsed time counter in the
playback, recording or stop mode.
To stop the tape and play back a picture step
by step. (except for during fast forwarding and fast rewinding)
In combination with /: to search for
previous or next recording on the cassette.
To view the picture in slow motion.
To change stereo sound and 2nd language.
To change the picture setting.
To set a TIMER programming with the SHOWVIEW
system.
To programme a recording with the function
TURBO TIMER.
Doesn’t work on this model.
SYSTEM
TURBO TIMER
SV/V+
SMART PICTURE
AUDIO
SLOW
INDEX
STILL
CLEAR
STATUS/EXIT
P–P+
0..9
STANDBY/ON
REC
Buttons with TV feature
To eliminate the TV’s sound. Press again to restore the volume.
To adjust the TV’s volume.
To select a programme number on the TV.
TV-PROG.–
TV-PROG.+
TV-VOL – TV-VOL +
MUTE
You can use this remote control to operate
some functions of Philips TVs.
1 2 3
4 5 6
7 8 9
0
STILL
STOP
MENU
REW FWD
PLAYSTATUS/EXIT CLEAR
REC STANDBY/ON
TV-PROG.TV-VOL
INDEXMUTE
TURBO
TIMER
SMART
PICTURE
SLOW SYSTEM
AUDIOSV/V+
PP
To call up main menu of VCR.
When tape playback is stopped, press to fast forward the tape
at high speed. During playback, press to fast forward the tape while the
picture stays on the screen. To store or confirm entry in the menu.
When tape playback is stopped, press to rewind the tape at
high speed. During playback, press to rewind the tape while the picture stays
on the screen.To return the cursor in the menu.
To play back a tape, select an item in the menu of VCR.
To stop the tape, select an item in the menu of VCR.
STOP -
PLAY -
REW -
FWD -
MENU
The remote control

1-5-4 HG490IB
RF OUT
AV 2 (DECODER) AV 1 (TV)
AERIAL
AUDIO
OUTPUT
L
R
To switch off or on, interrupt menu function.
To select the programme number. During nor-
mal or slow motion playback, press to adjust the tracking.
To record the TV channel selected at this moment.
When tape playback is stopped, press to fast forward the tape at high
speed. During playback, press to fast forward the tape while the picture stays on
the screen.
When tape playback is stopped, press to rewind the tape at high speed.
During playback, press to rewind the tape while the picture stays on the screen.
To play back a tape.
To stop the tape and eject the cassette.
White and red socket Audio input socket left/right: To connect a camcorder or a
video recorder.
Yellow socket Video input socket: To connect a camcorder or a video recorder.
FRONT A/V CONNECTORS
STOP/EJECT
PLAY
REW.
FWD.
RECORD
PROGRAMME-PROGRAMME+
STANDBY/ON
To connect an audio Hi-Fi amplifier.
To connect a satellite receiver, decoder, video recorder, etc.
To connect the TV.
To connect the aerial cable.
To connect the TV.
RF OUT
AERIAL
AV1(TV)
AV2(DECODER)
AUDIO OUTPUT L R
Front of your VCR
Back of your VCR

1-5-5 HG490IB
[ VR750/07, VR752/07 ]
Buttons for VCR feature only
To record the TV channel selected at this moment.
To switch off or on, interrupt menu function.
Press to select channels at VCR.
To select the programme number. During normal
or slow motion playback, press to adjust the tracking.
To access or remove the VCR’s on-screen
status display. To exit on-screen menus.
To delete last entry. To clear a programmed
recording (TIMER). To reset the elapsed time counter in the
playback, recording or stop mode.
To stop the tape and play back a picture step by
step. (except for during fast forwarding and fast rewinding)
In combination with /: to search for
previous or next recording on the cassette.
To view the picture in slow motion.
To change stereo sound and 2nd language.
To change the picture setting.
To set a TIMER programming with the VIDEO Plus+
system.
To programme a recording with the function
TURBO TIMER.
Doesn’t work on this model.
SYSTEM
TURBO TIMER
SV/V+
SMART PICTURE
AUDIO
SLOW
INDEX
STILL
CLEAR
STATUS/EXIT
P–P+
0..9
STANDBY/ON
REC
You can use this remote control to operate
some functions of Philips TVs.
1 2 3
4 5 6
7 8 9
0
STILL
STOP
MENU
REW FWD
PLAYSTATUS/EXIT CLEAR
REC STANDBY/ON
TV-PROG.TV-VOL
INDEXMUTE
TURBO
TIMER
SMART
PICTURE
SLOW SYSTEM
AUDIOSV/V+
PP
To call up main menu of VCR.
When tape playback is stopped, press to fast forward the
tape at high speed. During playback, press to fast forward the tape while the
picture stays on the screen. To store or confirm entry in the menu.
When tape playback is stopped, press to rewind the tape at
high speed. During playback, press to rewind the tape while the picture stays
on the screen.To return the cursor in the menu.
To play back a tape, select an item in the menu of VCR.
To stop the tape, select an item in the menu of VCR.
Buttons with TV feature
To eliminate the TV’s sound. Press again to restore the volume.
To adjust the TV’s volume.
To select a programme number on the TV.
TV-PROG.–
TV-PROG.+
TV-VOL – TV-VOL +
MUTE
STOP -
PLAY -
REW -
FWD -
MENU
The remote control

1-5-6 HG490IB
RF OUT
AV 2 (DECODER) AV 1 (TV)
AERIAL
AUDIO
OUTPUT
L
R
To switch off or on, interrupt menu function.
To select the programme number. During nor-
mal or slow motion playback, press to adjust the tracking.
To record the TV channel selected at this moment.
When tape playback is stopped, press to fast forward the tape at high
speed. During playback, press to fast forward the tape while the picture stays
on the screen.
When tape playback is stopped, press to rewind the tape at high speed.
During playback, press to rewind the tape while the picture stays on the screen.
To play back a tape.
To stop the tape and eject the cassette.
White and red socket Audio input socket left/right: To connect a camcorder or a
video recorder.
Yellow socket Video input socket: To connect a camcorder or a video recorder.
FRONT A/V CONNECTORS
STOP/EJECT
PLAY
REW.
FWD.
RECORD
PROGRAMME-PROGRAMME+
STANDBY/ON
To connect an audio Hi-Fi amplifier.
To connect a satellite receiver, decoder, video recorder, etc.
To connect the TV.
To connect the aerial cable.
To connect the TV.
RF OUT
AERIAL
AV1(TV)
AV2(DECODER)
AUDIO OUTPUT L R
Front of your
Back of your VCR
VCR

1-5-7 HG490IB
[ VR750/58, VR752/58 ]
Buttons for VCR feature only
To record the TV channel selected at this moment.
To switch off or on, interrupt menu function.
Press to select channels at VCR.
To select the programme number. During normal or
slow motion playback, press to adjust the tracking.
To access or remove the VCR’s on-screen
status display. To exit on-screen menus.
To delete last entry. To clear a programmed
recording (TIMER). To reset the elapsed time counter in the
playback, recording or stop mode.
To stop the tape and play back a picture step by
step. (except for during fast forwarding and fast rewinding)
In combination with /: to search for
previous or next recording on the cassette.
To view the picture in slow motion.
To change stereo sound and 2nd language.
To change the picture setting.
To set a TIMER programming with the SHOWVIEW
system.
To programme a recording with the function
TURBO TIMER.
To change the Video (Colour) System.
SYSTEM
TURBO TIMER
SV/V+
SMART PICTURE
AUDIO
SLOW
INDEX
STILL
CLEAR
STATUS/EXIT
P–P+
0..9
STANDBY/ON
REC
Buttons with TV feature
To eliminate the TV’s sound. Press again to restore the volume.
To adjust the TV’s volume.
To select a programme number on the TV.
TV-PROG.–
TV-PROG.+
TV-VOL – TV-VOL +
MUTE
You can use this remote control to operate
some functions of Philips TVs.
1 2 3
4 5 6
7 8 9
0
STILL
STOP
MENU
REW FWD
PLAYSTATUS/EXIT CLEAR
REC STANDBY/ON
TV-PROG.TV-VOL
INDEXMUTE
TURBO
TIMER
SMART
PICTURE
SLOW SYSTEM
AUDIOSV/V+
PP
To call up main menu of VCR.
When tape playback is stopped, press to fast forward the
tape at high speed. During playback, press to fast forward the tape while
the picture stays on the screen. To store or confirm entry in the menu.
When tape playback is stopped, press to rewind the tape at
high speed. During playback, press to rewind the tape while the picture
stays on the screen.To return the cursor in the menu.
To play back a tape, select an item in the menu of VCR.
To stop the tape, select an item in the menu of VCR.
STOP -
PLAY -
REW -
FWD -
MENU
The remote control

1-5-8 HG490IB
RF OUT
AV 2 (DECODER) AV 1 (TV)
AERIAL
AUDIO
OUTPUT
L
R
To switch off or on, interrupt menu function.
To select the programme number. During
normal or slow motion playback, press to adjust the tracking.
To record the TV channel selected at this moment.
When tape playback is stopped, press to fast forward the tape at high speed.
During playback, press to fast forward the tape while the picture stays on the
screen.
When tape playback is stopped, press to rewind the tape at high speed. During
playback, press to rewind the tape while the picture stays on the screen.
To play back a tape.
To stop the tape and eject the cassette.
White and red socket Audio input socket left/right: To connect a camcorder or a video
recorder.
Yellow socket Video input socket: To connect a camcorder or a video recorder.
FRONT A/V CONNECTORS
STOP/EJECT
PLAY
REW.
FWD.
RECORD
PROGRAMME-PROGRAMME+
STANDBY/ON
To connect an audio Hi-Fi amplifier.
To connect a satellite receiver, decoder, video recorder, etc.
To connect the TV.
To connect the aerial cable.
To connect the TV.
RF OUT
AERIAL
AV1(TV)
AV2(DECODER)
AUDIO OUTPUT L R
Front of your
Back of your VCR
VCR

1-6-3 HG490SNA
SIGNAL NAME ABBREVIATIONS
[ VR750/ (02, 07, 16, 58), VR752/ (07, 16, 58) ]
Signal Name Function
16P SCART 16Pin Control Signal
8POUT-1 SCART 1 8Pin Output Control
Signal
8POUT-2 SCART 2 8Pin Output Control
Signal
A-COM Audio Head Common
A-IN Audio Signal Input
A-MODE Hi-Fi Tape Detection Signal
A-MUTE-H Audio Mute Control Signal (Mute
= “H”)
A-OUT Audio Signal Output
A-PB/REC Normal Audio Play Back/Record
Signal
AE-H Audio Erase Head
AFC Automatic Frequency Control
Signal
AGC IF AGC Comparator Signal
AL+12V Always +12V with AC Plug
Connected
AL+12V/+20.5V Always +12V/+20.5V with AC
Plug Connected
AL+15V Always +15V with AC Plug
Connected
AL+44V Always +9V with AC Plug
Connected
AL+5V Always +5V with AC Plug
Connected
AL+9V Always +9V with AC Plug
Connected
AMPC CTL AMP Connected Terminal
AMPVcc AMPVcc
AMPVREF IN V-Ref for CTL AMP
AMPVREF OUT V-Ref for CTL AMP
AVcc A/D Converter Power Input/
Standard Voltage Input
C-CONT Capstan Motor Control Signal
C-F/R
Capstan Motor FWD/REV
Control Signal (FWD=”L”/
REV=”H”)
C-FG Capstan Motor Rotation
Detection Pulse
C-POW-SW Capstan Power Switching Pulse
C-ROTA Color Phase Rotary Changeover
SIgnal
C-SYNC Composite Synchronized Pulse
CLKSEL Clock Select (GND)
COLOR-IN
SECAM or MESECAM Chroma
Video Input Signal at Super
Impose
CTL (+) Playback/Record Control Signal
(+)
CTL (-) Playback/Record Control Signal
(-)
CTLAMP out To Monitor for CTL AMP Output
D-CONT Drum Motor Control Signal
D-PFG Drum Motor Pulse Generator
D-REC-H Delayed Record Signal
D-V-SYNC Dummy V-sync Output
DAVN-L VPS/PDC Data Receive = “L”
DRV-CLK LED Clock Driver IC Control
Clock
DRV-DATA LED Clock Driver IC Control
Data
DRV-STB LED Clock Driver IC Chip Select
Signal
END-S Tape End Position Detect Signal
FE-H Full Erase Head
FF/REW-L CTL Frequency Characteristics
Switching Signal (FF/REW=”L”)
FSC-IN
[4.43MHz] 4.43MHz Clock Input
FTV-IN Comparator Input of Video
Signal for Follow TV
H-A-COMP Head Amp Comparator Signal
H-A-SW Video Head Amp Switching
Pulse
Hi-Fi-A Hi-Fi Audio Head
Hi-Fi-COM Hi-Fi Audio Head Common
Hi-Fi-H-SW Hi-Fi Audio Head Switching
Pulse
HLF LPF Connected Terminal (Slicer)
IIC-BUS SCL I2C BUS Control Clock
IIC-BUS SDA I2C BUS Control Data
JK1-8P-OUT SCART 8Pin Output Control
Signal
Signal Name Function

1-6-4 HG490SNA
KEY-1 Key Scan Input Signal 1
KEY-2 Key Scan Input Signal 2
LD-SW Deck Mode Position Detector
Signal
LINE-MUTE Audio Mute Control Signal
LM-FWD/REV Loading Motor Control Signal
LP LP
MOD-A Modulator Audio Output Signal
N-A-PB Normal Audio Playback
N-A-REC Normal Audio Recording
OSCin Clock Input for letter size
OSCout Clock Output for letter size
OSD-V-IN OSD Video Signal Input
OSD-V-OUT OSD Video Signal Output
OSDVcc OSDVcc
OSDVss OSDVss
P-DOWN-L Power Voltage Down Detector
Signal
P-ON+15V +15V at Power-On Signal
P-ON+44V +44V at Power-On Signal
P-ON+5V +5V at Power-On Signal
P-ON-H Power On Signal at High
P80/C P80/C Terminal
PG-DELAY Video Head Switching Pulse
Signal Adjusted Voltage
POW-SAF P-ON Power Detection Input
Signal
REC-SAF-SW
Recording Safety SW Detect
(With Record tab="L"/With out
Record tab="H")
REMOCON-IN Remote Control Sensor
RESET System Reset Signal (Reset=”L”)
RESET+5V +5V at System Reset Signal
RF-SW Video Head Switching Pulse
RGB-
THROUGH
SCART 2 RGB Through Control
Signal
S-REEL Supply Reel Rotation Signal
SC2-IN Input Signal from Pin 8 of
SCART2
SECAM-H SECAM Mode at High
SIF Tuner Audio Intermediate
Frequency Signal
ST-S Tape Start Position Detector
Signal
T-REEL Take Up Reel Rotation Signal
Signal Name Function
TIMER+5V +5V at Timer
TU-AUDIO Tuner Audio Input Signal
TU-VIDEO Tuner Video Input Signal
V(L) Video L Head
V(R) Video R Head
V-COM Video Head Common
V-ENV Video Envelope Comparator
Signal
V-IN Video Signal Input
V-OUT Video Signal Output
Vcc Vcc
VIDEO Video Signal
Vss Vss(GND)
X-IN Main Clock Input
X-OUT Main Clock Input
XC-IN Sub Clock
XC-OUT Sub Clock
Signal Name Function

1-7-4 HG490DC
CABINET DISASSEMBLY INSTRUCTIONS
[ VR750/ (02, 07, 16, 58), VR752/ (07, 16, 58) ]
1. Disassembly Flowchart
This flowchart indicates the disassembly steps to gain
access to item(s) to be serviced. When reassembling,
follow the steps in reverse order. Bend, route, and
dress the cables as they were originally.
2. Disassembly Method
(1): Identification (location) No. of parts in the figures
(2): Name of the part
(3): Figure Number for reference
(4): Identification of parts to be removed, unhooked,
unlocked, released, unplugged, unclamped, or
desoldered.
P=Spring, L=Locking Tab, S=Screw,
CN=Connector
*=Unhook, Unlock, Release, Unplug, or Desolder
e.g. 2(S-2) = two Screws (S-2),
2(L-2) = two Locking Tabs (L-2)
(5): Refer to “Reference Notes.”
Reference Notes
CAUTION: Locking Tabs (L-1) and (L-2) are fragile.
Be careful not to break them.
1. Remove five Screws (S-2), three Screws (S-3) and
Screw (S-4). Then, slowly lift the VCR Chassis Unit
(Deck Assembly, Jack CBA and Main CBA) up
while releasing two Locking Tabs (L-3).
2. When reassembling, solder wire jumpers as shown
in Fig. D5.
3. Before installing the Deck Assembly, be sure to
place the pin of LD-SW on Main CBA as shown in
Fig. D6. Then, install the Deck Assembly while
aligning the hole of Cam Gear with the pin of LD-
SW, the shaft of Cam Gear with the hole of LD-SW
as shown in Fig. D6.
ID/
LOC.
No.
PART
REMOVAL
Fig.
No.
REMOVE/*UNHOOK/
UNLOCK/RELEASE/
UNPLUG/DESOLDER
Note
[1] Top Case D1 7(S-1) -
[2] Front
Assembly D2 *3(L-1), *4(L-2) -
[3]
VCR
Chassis
Unit
D3 5(S-2), 3(S-3), (S-4),
*2(L-3) 1
[4] Jack CBA D4 Desolder, (S-5) -
[5] Deck
Assembly
D5,
D6 2(S-6), Desolder 2,3
[6] Main CBA D5 (L-4) -
[7] Cylinder
Shield D5 (S-7) -
[8] Rear
Panel D5 ---------- -
↓
(1)
↓
(2)
↓
(3)
↓
(4)
↓
(5)
[5] Deck Assembly
[4] Jack CBA
[1] Top Case
[2] Front Assembly
[3] VCR Chassis Unit
[6] Main CBA
[8] Rear Panel
[7] Cylinder Shield

1-7-5 HG490DC
Fig. D1
[1] Top Case
(S-1)
(S-1)
(S-1)
Fig. D2
(L-2)
(L-1)
[2] Front
Assembly (L-2)
Fig. D3
[3] VCR
Chassis Unit
(S-2)
(S-2)
(S-4)
(S-2)
(S-2)
(L-3)
(S-3)
(S-3)
(S-3)
Fig. D4
(S-5)
[4] Jack CBA
Desolder

1-7-6 HG490DC
(S-7)
FE Head
Cylinder Assembly
ACE Head
Assembly
[7] Cylinder Shield
[6] Main CBA
(S-6)
(S-6)
From
FE Head
From
Cylinder
Assembly
From
ACE Head
Assembly
Lead with
white stripe
Lead with
blue stripe
Desolder
from bottom
Lead with
blue stripe
From
Capstan Motor
Assembly
Lead connections of Deck Assembly and Main CBA
Printing
side
TOP VIEW
[8] Rear Panel
(L-4) [5] Deck
Assembly
Fig. D5
Fig. D6
LD-SW Pin
Hole
Hole
Shaft
Cam Gear
[6] Main CBA
[5] Deck Assembly
[6] Main CBA
SW507
LD-SW
Pin

1-9-6
BLOCK DIAGRAMS
Servo/System Control Block Diagram
HG490BLS
M
M
LOADING MOTOR
CYLINDER ASSEMBLY CAPSTAN MOTOR
DRUM MOTOR
PG SENSOR
CONTROL HEAD
CL504
AC HEAD ASSEMBLY
MAIN CBA
KEY- 2
C-CONT
C-FG
D-PFG
ST-S T-REEL C-F/R
KEY- 1REMOCON-IN
CTL(+)
RESET FTV-IN
REC-SAF-SW
PG-DELAY
CTL(-)
D-V-SYNC
D-REC-H
RF-SW
H-A-SW
C-ROTA
END-S
14
90
87
94 95 76 10
4
80 34 78
2
13 15 18 33 16
31
8 7
RS501
REMOTE SENSOR
LM-FWD/REV
81
D-CONT
77
(DECK ASSEMBLY)
T-REEL
TU-VIDEO
FROM VIDEO BLOCK V-IN1
Q771, Q772
Q501
RESET
Q503
S-REEL
79
SW-POINT
AL+5V
VR501
TIMER+5V
AND
S-REEL
PS503
TP506
IIC-BUS SDA IIC-BUS SDA
IIC-BUS SCL
A-MUTE-H
IIC-BUS SDA
IIC-BUS SCL
Hi-Fi-H-SW
A-MODE
A-MUTE-H
Hi-Fi-H-SW
A-MODE
H-A-COMP
17
V-ENV
6
P-ON-H C-POW-SW
P-ON-H C-POW-SW
P-DOWN-L
67 66
86
P-DOWN-L
C-SYNC
58
SW506
FROM/TO VIDEO BLOCK FROM/TO Hi-Fi AUDIO BLOCK TO AUDIO BLOCK
SDA SDA SCL SCL
TU701(TUNER UNIT)
IC503 (MEMORY)
72 32 19 83
IIC-BUS SCL
D-V-SYNC
D-REC-H
RF-SW
H-A-SW
C-ROTA
IIC-BUS SDA
H-A-COMP
V-ENV
C-SYNC
IIC-BUS SCL
71
3 5
SDA SCL
12 11
LD-SW
9
AL+12V/+20.5V P-ON+15V
AL+5V
AL+5V
SW507
AL+12V P-ON+5V
LD-SW
AL+5V
D502
S-LED
FROM/TO POWER SUPPLY BLOCK
LINE-MUTE
KEY SWITCH
KEY SWITCH
TP507
SENS-INH
CAPSTAN MOTOR
" " = SMD
NOTE FOR WIRE CONNECTORS: 1. PREFIX SYMBOL "CN" MEANS CONNECTOR. (CAN DISCONNECT AND RECONNECT
.)
2. PREFIX SYMBOL "CL" MEANS WIRE-SOLDER HOLES OF THE PCB. (WIRE IS SOLDERED DIRECTLY.)
TEST POINT INFORMATION
:INDICATES A TEST POINT WITH A JUMPER WIRE ACROSS A HOLE IN THE PCB. :USED TO INDICATE A TEST POINT WITH A COMPONENT LEAD ON FOIL SIDE. :USED TO INDICATE A TEST POINT WITH NO TEST PIN. :USED TO INDICATE A TEST POINT WITH A TEST PIN.
IC561 (LED DISPLAY)
IC501 (SERVO/SYSTEM CONTROL)
IC771 (COMPARATOR)
DRV-DATA DRV-STB DRV-CLK
DRV-DATA
DRV-STB DRV-CLK
FP562
LED DISPLAY
D1 D2 D3 D4
a
f
j
b
c
d
23 22 21
28
2 1
68 69 70
20 11 16 14 13
e
12 17
7
LINE-MUTE
28
5 6
914
13
8
11 10
264
4 5
CL502
12
P-ON+15V
11
AL+12V(2)
10
GND
9
D-PFG
8
D-CONT
7
LM-FWD/REV
6
GND
5
C-CONT
4
C-F/R
3
C-FG
2
P-ON+5V
1
AL+12V/+20.5V
SENSOR CBA SENSOR CBA
END-S
ST-S
Q504
Q505
REC-SAFETY
P-ON+5V
END-S
P-ON+5V
CL504
2 CTL(+) 1 CTL(-)
M
DAVN-L
56
DAVN-L
[ VR750/ (02, 07, 16, 58), VR752/ (07, 16, 58) ]

1-9-7
Video Block Diagram
HG490BLV
CYLINDER ASSEMBLY
V(R)-1
V-COM
V(L)-1
CL253
1 2 3
(DECK ASSEMBLY)
VIDEO (R)-1 HEAD
SP HEAD AMP EP HEAD AMP
REC FM AGC
FROM/TO SERVO/SYSTEM CONTROL BLOCK
FROM SERVO/SYSTEM CONTROL BLOCK
C-SYNC
RF-SW
D-REC-H
C-ROTA
D-V-SYNC
H-A-SW
H-A-COMP
V-ENV
LUMINANCE SIGNAL PROCESS
CHROMINANCE SIGNAL PROCESS
PB-H OUT
C-SYNC
V-ENV
H-A-COMP
H-A-SW
D-V-SYNC
C-ROTA/RF-SW
VIDEO (L)-1 HEAD
VIDEO (L)-2 HEAD
VIDEO (R)-2 HEAD
V(L)-2
V-COM
V(R)-2
4 5 6
TU701(TUNER UNIT)
IC301 (Y/C SIGNAL PROCESS)
IC501 (OSD)
REC-VIDEO SIGNAL PB-VIDEO SIGNAL MODE: SP/REC
SERIAL
DECORDER
V-OUT1 1
V-IN1
1
33
V-OUT2 1
V-IN2 3
1
3
JACK CBA
48 50 52 56
24
6
50
52
19 20
JK101
V-OUT1 V-IN1
19 20
JK102
CL151 CL152
CL101 CL102
V-OUT2 V-IN2
61 63
96 95 93 94 90 89 88 87
CHARA. INS.
CCD 1H DELAY
SP
BYPASS
MUTE
PB/EE
IN1
TUNER
IN1
TUNER
MUTE
PB/EE
FRT
IN2
FRT
IN2
AGC
PR
R Y C
P
RPRP
EP
Y. DELAY
Y/C MIX
+
21 7978
AGC VXO
OSD CHARACTER MIX
FBC
1/2
58 59
65
252928 44
IIC-BUS SDA IIC-BUS SCL
69684643
" " = SMD
NOTE FOR WIRE CONNECTORS: 1. PREFIX SYMBOL "CN" MEANS CONNECTOR. (CAN DISCONNECT AND RECONNECT
.)
2. PREFIX SYMBOL "CL" MEANS WIRE-SOLDER HOLES OF THE PCB. (WIRE IS SOLDERED DIRECTLY.)
TEST POINT INFORMATION
:INDICATES A TEST POINT WITH A JUMPER WIRE ACROSS A HOLE IN THE PCB. :USED TO INDICATE A TEST POINT WITH A COMPONENT LEAD ON FOIL SIDE. :USED TO INDICATE A TEST POINT WITH NO TEST PIN. :USED TO INDICATE A TEST POINT WITH A TEST PIN.
67 84 83 71 62 70
D-REC-H
80
BUFFER
Q101
BUFFER
Q102
J23
V-OUT
WF1
TP301
X301
4.433619MHz C-PB
WF3
VIDEO OUT
TU-VIDEO V-IN1TO
SERVO/SYSTEM CONTROL BLOCK
VIDEO IN
BUFFER
Q351
MAIN CBA
TP502
RF-SW
WF2
54
55
COLOR -IN
IC640 (VPS)
VPS-V IIC-BUS SDA DAVN-L IIC-BUS SCL
6
14
7
16
DAVN-L
JK756 V-IN
FRONT
I,L
Comparison Chart of Models & Marks
Model Mark
VR750/02 VR750/07
VR750/16
F
G
H
VR750/58 I
VR752/07
VR752/16
J
VR752/58
K
L

1-9-8
Audio Block Diagram
HG490BLA
REC AMP
100
3
AUTO BIAS
2 1
+5V
+5V
Q401
Q406
BIAS OSC
Q402
N-A-PB
TO Hi-Fi AUDIO BLOCK N-A-REC
Q405 (PB=ON)
Q403
5EQ
AMP 98
7
LINE AMP
REC-ON
AUDIO HD-SW CONTROL
MUTE 11
6
PB-ON
SP/LP-ON
P
TUNER IN2
IN1
R
ALC
DET
ALC
IC301 (AUDIO SIGNAL PROCESS) 1513 17
3 A-PB/REC
CL504
4 A-COM 6 AE-H 5 AE-H/FE-H
AUDIO HEAD AUDIO ERASE HEAD
ACE HEAD ASSEMBLY
FE HEAD
2 FE-H 1 FE-H-GND
CL501
MAIN CBA
PB-AUDIO SIGNAL REC-AUDIO SIGNAL
Mode : SP/REC
71
A-MUTE-H
IIC-BUS SCL
IIC-BUS SDA TO SERVO/SYSTEM
CONTROL BLOCK
FULL ERASE HEAD
68 69
SERIAL
DECODER
(DECK ASSEMBLY)
" " = SMD
NOTE FOR WIRE CONNECTORS: 1. PREFIX SYMBOL "CN" MEANS CONNECTOR. (CAN DISCONNECT AND RECONNECT
.)
2. PREFIX SYMBOL "CL" MEANS WIRE-SOLDER HOLES OF THE PCB. (WIRE IS SOLDERED DIRECTLY.)
TEST POINT INFORMATION
:INDICATES A TEST POINT WITH A JUMPER WIRE ACROSS A HOLE IN THE PCB. :USED TO INDICATE A TEST POINT WITH A COMPONENT LEAD ON FOIL SIDE. :USED TO INDICATE A TEST POINT WITH NO TEST PIN. :USED TO INDICATE A TEST POINT WITH A TEST PIN.
12
16
INV
AT T

1-9-9
Hi-Fi Audio Block Diagram
HG490BLH
ENV DET
LOGIC
R L
HOLD PULSE
LIM
OUTPUT SELECT
REC-AUDIO SIGNALPB-AUDIO SIGNAL Mode : SP/REC
IIC-BUS SDA
IIC-BUS SCL
A-MODE
LINE-MUTE
MUTE
MUTE-ON MUTE-ON
Hi-Fi-H-SW
" " = SMD
NOTE FOR WIRE CONNECTORS: 1. PREFIX SYMBOL "CN" MEANS CONNECTOR. (CAN DISCONNECT AND RECONNECT
.)
2. PREFIX SYMBOL "CL" MEANS WIRE-SOLDER HOLES OF THE PCB. (WIRE IS SOLDERED DIRECTLY.)
TEST POINT INFORMATION
:INDICATES A TEST POINT WITH A JUMPER WIRE ACROSS A HOLE IN THE PCB. :USED TO INDICATE A TEST POINT WITH A COMPONENT LEAD ON FOIL SIDE. :USED TO INDICATE A TEST POINT WITH NO TEST PIN. :USED TO INDICATE A TEST POINT WITH A TEST PIN.
IF SIGNAL PROCESS
N-A-REC
TO AUDIO BLOCK N-A-PB
AFV CBA
TU-AUDIO(R)
4
TU-AUDIO(L)
5
4
5
CN701 CN1
SIF 2
2
CN701
CN1
TU701
AUDIO IN
SIF OUT
2
22
JACK CBA
MAIN CBA
JK101
A-IN1(R) A-IN1(L)
2 6 2 6 1 3 1 3
JK102
CL151 CL152
CL101 CL102
A-IN2(R) A-IN2(L)
A-OUT1(R) A-OUT1(L) A-OUT2(R) A-OUT2(L)
A-IN2(R)
(Hi-Fi AUDIO SIGNAL PROCESS)
9
A-IN2(L) 8
9
8
A-OUT2(R) 6
A-OUT2(L) 11
6
11
A-IN1(R) 9
A-IN1(L) 7
9
7
A-OUT1(R) 5
A-OUT1(L) 11
5
11
IC451
Hi-Fi AUDIO (R) HEAD Hi-Fi AUDIO (L) HEAD
CYLINDER ASSEMBLY
Hi-Fi-A(R) 7 Hi-Fi-COM 8 Hi-Fi-A(L) 9
CL253
48
47
14
15
R-CH INSEL
L-CH INSEL
ALC
SW
SW ALC
62 61 71
70
24 26 27
34 33
L-CH BPF
COMP
SW NOISE
COMP
SW NOISE
R-CH BPF
VCO
LPF
LIM DEV
VCO
LPF
LIM DEV
MIX V/I
NOISE DET
DO DET
P P R R
VCO MUTE
73 74 72 76 77 75
37 38
21 53
39
L-CH PNR
ALC
R-CH PNR
ALC
67 65 52 56 54 50 60
2 6
10
8 4
78 80
+
Q451
FROM/TO SERVO/SYSTEM CONTROL BLOCK
(DECK ASSEMBLY)
JK751
A-OUT (L) A-OUT (R)
SUB JACK CBA
CL509
A-OUT1(L)
2
A-OUT1(R)
1
JK758 A-IN(R) JK757 A-IN(L)
FRONT
(TUNER UNIT)

1-9-10
Power Supply Block Diagram
HG490BLP
2 4
16
6 7
CAUTION
FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, REPLACE ONLY WITH THE SAME TYPE T1.6AL/250V FUSE.
NOTE : The voltage for parts in hot circuit is measured using hot GND as a common terminal.
CAUTION ! Fixed voltage (or Auto voltage selectable ) power supply circuit is used in this unit. If Main Fuse (F001) is blown, check to see that all components in the power supply circuit are not defective before you connect the AC plug to the AC power supply. Otherwise it may cause some components in the power supply circuit to fail.
COLD
MAIN CBA
HOT CIRCUIT. BE CAREFUL.
HOT
IC001 ERROR VOLTAGE DET
Q002
Q003
Q001
F001 L003
LINE FILTER
BRIDGE RECTIFIER
D001 - D004
1 23
4
Q004
AC001
T001
P-ON+44V P-ON+15V
12
P-ON-H AL+12V/+20.5V AL+9V AL+12V C-POW-SW AL+5V TIMER+5V P-ON+5V P-DOWN-L
Q051
Q053
Q054
Q056
Q052
Q057
Q058
13 15 14 11 17 18
T1.6A L 250V
Q055
Q059
SHUNT REGULATOR

Main 1/7 Schematic Diagram Parts Location Guide
1-10-31
[ VR750/ (02, 07, 16, 58), VR752/ (07, 16, 58) ]
Ref No. Position Ref No. Position Ref No. Posi tion
C501 B-1 CL501 A-2 R524 B-4
C502 B-1 CL502 F-4 R525 B-3
C506 C-1 CL504 A-2 R526 A-2
C508 E-2 R527 A-2
C510 E-2 D501 E-4 R528 B-1
C511 E-2 D502 A-1 R529 A-1
C512 E-2 D552 E-3 R530 E-1
C513 E-2 D553 E-2 R531 E-1
C514 E-2 R533 D-1
C515 E-2 IC501 C-3 R551 E-3
C516 E-2 IC503 A-4 R552 E-3
C517 E-4 R553 F-2
C518 E-4 L501 A-1 R555 C-1
C519 B-4 L851 D-3 R556 C-1
C520 A-3 R557 C-1
C521 A-2 Q501 E-2 R558 C-1
C522 A-2 Q503 D-1 R615 D-1
C523 A-2 Q551 E-3 R616 D-1
C524 A-2 Q552 E-3 R621 A-3
C526 A-2 R622 A-3
C527 B-2 R501 B-1 R851 D-3
C528 A-2 R502 B-2 R852 D-3
C530 B-2 R503 C-2 R853 D-4
C531 B-1 R504 B-1
C532 A-3 R505 B-1 SW506 D-1
C533 A-3 R506 C-1
C535 E-1 R508 E-4 VR501 B-1
C563 E-4 R509 D-1
C564 E-4 R510 C-4 X501 D-2
C567 F-4 E511 E-2 X502 D-2
C851 E-3 R513 E-2
C852 E-3 R514 E-2 PS503 E-1
C853 D-3 R516 D-2 RS501 B-2
C854 E-3 R517 D-3
C855 D-3 R518 F-3 TP501 A-2
C856 D-4 R520 E-4 TP502 C-1
C858 E-4 R521 E-4
C859 D-4 R522 E-4
C862 D-3 R523 B-4
VARIABLE RESISTOR
CRYSTAL OSCILLATORS
MISCELLANEOUS
TEST POINTS
SWITCH
RESISTORS
CAPACITORS CONNECTORS RESISTORS
TRANSISTORS
ICS
DIODES
COILS

1-10-32 1-10-33 HG490SCM1
THE SAME VOLTAGE FOR
BOTH PLAY & REC MODES.
INDICATES THAT THE VOLTAGE
IS NOT CONSISTENT HERE.
MODE: SP/REC PLAY MODE
REC MODE
123
5.0 5.0
(2.5)
~
“ “ = SMD
Main 1/7 Schematic Diagram IC501 KEY VOLTAGE CHART
0.00 ~ 0.51V POWER STOP/EJECT
0.51 ~ 0.92V CH DOWN REW
0.92 ~ 1.27V CH UP PLAY
1.27 ~ 1.61V ---------------- FF
1.61 ~ 1.98V ---------------- --------------
1.98 ~ 2.39V REC/OTR --------------
2.39 ~ 2.90V ---------------- --------------
2.90 ~ 3.60V SENS-INH --------------
3.60 ~ 4.30V ---------------- --------------
4.30 ~ 5.00V KEY OFF KEY OFF
Pin No.
Voltage KEY 1 (7 PIN) KEY 2 (8 PIN)
Comparison Chart of
Models and Marks
MODEL MARK
VR750/02 F
VR750/07 G
VR750/16 H
VR750/58 I
VR752/07 J
VR752/16 K
VR752/58 L

Main 2/7 & Sensor Schematic Diagrams
1-10-34 1-10-35 HG490SCM2
THE SAME VOLTAGE FOR
BOTH PLAY & REC MODES.
INDICATES THAT THE VOLTAGE
IS NOT CONSISTENT HERE.
MODE: SP/REC PLAY MODE
REC MODE
123
5.0 5.0
(2.5)
~
“ “ = SMD
D1 D2 D3 D4
a
b
c
d
e
g
f
D1 D2 D3 D4
a
b
c
d
e
f
g
c
d
e
f
g
c
d
e
f
g
c
d
e
f
g
h
j
i
a
b
c
d
e
f
g
a
b
a
b
a
b
FP562 MATRIX CHART
Comparison Chart of
Models and Marks
MODEL MARK
VR750/02 F
VR750/07 G
VR750/16 H
VR750/58 I
VR752/07 J
VR752/16 K
VR752/58 L