Luma VCR425 Service Manual
SERVICE MANUAL
Sec. 1: Main Section
I
Specifications
I
Preparation for Servicing
I
Adjustment Procedures
I
Schematic Diagrams
I
CBA’s
Sec. 2: Deck Mechanism Section
I
Standard Maintenance
I
Alignment for Mechanism
I
Disassembly/Assembly of Mechanism
I
Alignment Procedures of Mechanism
Sec. 3: Exploded views
and Parts List Section
I
Exploded views
I
Parts List
VIDEO CASSETTE RECORDER
VCR425
PAL
MAIN SECTION
VIDEO CASSETTE RECORDER
VCR425
Sec. 1: Main Section
I
Specifications
I
Preparation for Servicing
I
Adjustment Procedures
I
Schematic Diagrams
I
CBA’s
TABLE OF CONTENTS
Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1-1
Important Safety Precautions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2-1
Standard Notes for Servicing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3-1
Preparation for Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4-1
Cabinet Disassembly Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5-1
Electrical Adjustment Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6-1
Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7-1
Function Indicator Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7-9
Schematic Diagrams / CBA’s and Test Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8-1
Waveforms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9-1
Wiring Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10-1
IC Pin Function Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11-1
Lead Identifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-12-1
SPECIFICATIONS
Description Unit Minimum Nominal Maximum Remark
1. Video
1-1. Video Output (PB) Vp-p 0.8 1.0 1.2 FL6A
1-2. Video Output (R/P) Vp-p 0.8 1.0 1.2
1-3. Video S/N Y (R/P) dB 40 45
1-4. Video Color S/N AM (R/P) dB 37 41 SP Mode
1-5. Video Color S/N PM (R/P) dB 30 36 SP Mode
1-6. Resolution (PB) Line 230 245 SP Mode
2. Servo
2-1. Jitter Low µsec 0.07 0.12 SP Mode
2-2. Wow & Flutter % 0.3 0.5 SP Mode
3. Normal Audio
3-1. Output (PB) dBV -9 -6 -3 SP Mode
3-2. Output (R/P) dBV -9 -6 -1.5 SP Mode
3-3. S/N (R/P) dB 36 41 SP Mode
3-4. Distortion (R/P) % 1.0 4.0 SP Mode
3-5. Freq. resp (R/P) at 200Hz dB -7 -4 SP Mode
(-20dB ref. 1kHz) at 6kHz dB -10 -4 SP Mode
SP Mode,
W/O Burst
4. Tuner
4-1. Video output Vp-p 0.8 1.0 1.2 E-E Mode
4-2. Video S/N dB 39 42 E-E Mode
4-3. Audio output dB -10 -6 -2 E-E Mode
4-4. Audio S/N dB 40 46 E-E Mode
: Nominal specs represent the design specs. All units should be able to approximate these – some will exceed
Note
and some may drop s lightly bel ow these spec s. Limit sp ecs rep resent the a bsolute wo rst con dition that still migh t
be considered acceptable; In no case should a unit fail to meet limit specs.
1-1-1 HC341SP
IMPORTANT SAFETY PRECAUTIONS
Product Safety Notice
Some electrical and mechanical parts have special
safety-related char acteristics which are often not evi dent from visual inspection, nor can the protection
they give necessarily be obtained by replacing them
with components rated for higher voltage, wattage,
etc. Parts that have sp ecial safety characteristi cs are
identified by a ! on schematics and in parts lists. Use
of a substitute replacement that does not have the
same safety characteristics as the recommended
replacement part might create shock, fire, and/or other
hazards. The Prod uct’s Safety is under review continuously and new instructions are issued whenever
appropriate. Prior to shipment from the factory, our
products are carefully inspected to confirm with the
recognized product s afety and electrical codes of the
countries in which they are to be sold. However, in
order to maintain su ch com plian ce, it is equal ly imp ortant to implement the following precautions when a set
is being serviced
Precautions during Servicing
Parts identified by the ! symbol are critical for
A.
safety. Replace only with part number specified.
In addition to safety, other parts and assemblies
B.
are specified for conformance with regulations
applying to spur ious rad iation. T hese m ust also be
replaced only with specified re pla ce men ts .
Examples: RF converters, RF c ables, noise blocking capacitors, and noise blocking f ilters, etc.
Use specified internal wiring. Note especially:
C.
1)Wires covered with PVC tubing
2)Double insulated wires
3)High voltage leads
Use specified insulating materials for hazardous
D.
live parts. Note especially:
1)Insulation tape
2)PVC tubing
3)Spacers
4)Insulators for transistors
When replacing AC primary side components
E.
(transformers, power cord, etc.), wrap ends of
wires securely about the terminals before soldering.
Observe that the wires do not contact hea t produc-
F.
ing parts (heatsinks, oxid e met al film res istors, fusible resistors, etc.).
Check that replaced wires do not contact sharp
G.
edges or pointed parts.
When a power cord h as been repl aced, ch eck that
H.
5 - 6 kg of force in any direction will not loosen it.
.
Also check areas surrounding repaired locations.
I.
Be careful that foreign objects (screws, solder
J.
droplets, etc.) do not remain inside the set.
Crimp type wire connector
K.
The power tr ansformer uses crimp type connectors
which connect the power cord and the primary side
of the transformer. When replacing the transformer,
follow these steps carefully and precisely to prevent shock hazards.
Replacement procedure
1)Remove the old connector by cutting the wires at a
point close to the connector.
Important:
2)Strip about 15 mm of t he insulation fr om the ends
of the wires. If the wires are stranded, twist the
strands to avoid frayed conductors.
3)Align the lengths of the wires to be connected.
Insert the wires fully into the connector.
4)Use a crimping tool to crimp the metal sleeve at its
center. Be sure to crimp ful ly to the complete closure of the tool.
When connecting or disconnecting the internal con-
L.
nectors, first, disco nnect the AC plug from th e AC
outlet.
Do not re-use a connector. (Discard it.)
1-2-1 H8740SFP
Safety Check after Servicing
Examine the area surrounding the repaired location for
damage or deterioration. Obse rve that screws, parts,
and wires have been returned to their original positions. Afterwards, do the following tests and confirm
the specified values to verify compliance with safety
standards.
1. Clearance Distance
When replacing primary circuit components, confirm
specified clearan ce distance (d) and (d’ ) between soldered terminals, and between terminals and surrounding metallic parts. (See Fig. 1)
Table 1 : Ratings for selected area
AC Line Voltage Clearance Distance (d) (d’)
230 V
This table is unofficial and for reference only.
Note:
Be sure to confirm the precise values.
≥ 3mm(d)
≥ 6 mm(d’)
2. Leakage Current Test
Confirm the specified (or lower) leakage current
between B (earth ground, power cord plug prongs)
and externally exposed accessible parts (RF terminals, antenna terminals, video and audio input and
output terminals, microphone jacks, earphone jacks,
etc.) is lower than or equal to the specified value in the
table below.
Measuring Method (Power ON) :
Insert load Z between B (earth ground, power cord
plug prongs) and exposed accessible parts. Use an
AC voltmeter to measure acr oss the ter minals of l oad
Z. See Fig. 2 and the following table.
Chassis or Secondary Conductor
Primary Circuit Terminals
dd'
Exposed Accessible Part
Z
One side of
B
Power Cord Plug Prongs
AC Voltmeter
(High Impedance)
Fig. 1
Fig. 2
Table 2: Leakage current ratings for selected areas
AC Line Voltage Load Z Leakage Current (i)
2kΩ RES.
Connected in
230 V
This table is unofficial and for reference only. Be sure to confirm the precise values.
Note:
parallel
50kΩ RES.
Connected in
parallel
i≤0.7mA AC Peak
i≤2mA DC
i≤0.7mA AC Peak
i≤2mA DC
1-2-2 H8740SFP
One side of power cord plug
prongs (B) to:
RF or
Antenna terminals
A/V Input, Output
STANDARD NOTES FOR SERVICING
Circuit Board Indications
a. The output pin of the 3 pin Regulator ICs is indi-
cated as shown.
Top View
Out
b. For other ICs, pin 1 and every fifth pin are indicated
as shown.
Input
In
Pin 1
c. The 1st pin of every male connector is indica ted as
shown.
Pin 1
Bottom View
5
10
How to Remove / Install Flat Pack-IC
1. Removal
With Hot-Air Flat Pack-IC Desoldering Machine:
(1) Prepare the hot-air flat pack-IC desoldering
machine, then apply hot air to the Flat Pack-IC
(about 5 to 6 seconds). (Fig. S-1-1)
Fig. S-1-1
(2) Remove the flat pack-IC with tweezers while apply-
ing the hot air.
(3) B ottom of the flat pack-IC is fixed with glue to the
CBA; when removing en tire flat pack-IC, fir st apply
soldering iron to c en ter of the flat pack-IC and hea t
up. Then remove (glue will be melted). (Fig. S-1-6)
(4) R elease the fla t pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
.
Instructions for Connectors
1. When you connec t o r di s connec t the FF C ( Flex ible
Foil Connector) cable, be sure to first disconnect
the AC cord.
2. FFC (Flexible Foil Connector) cable should be
inserted parallel into the connector, not at an angle.
FFC Cable
Connector
CBA
* Be careful to avoid a short circuit.
Caution:
1. Do not supply hot air to the chip parts aroun d the
flat pack-IC for over 6 seconds because damage
to the chip parts may occur. Put masking tape
around the flat pack -IC to protect other parts from
damage. (Fig. S-1-2)
2. The flat pack-IC on the CB A is affixed with glue, so
be careful not to break or damage the foil of each
pin or the solder lands under the IC when removing
it.
Hot-air
Flat Pack-IC
Desoldering
CBA
Masking
Tape
Tweezers
Machine
Flat Pack-IC
Fig. S-1-2
1-3-1 NOTE_1
With Soldering Iron:
(1)Using desoldering braid, remove the solder from all
pins of the flat pack-IC. W hen you use solder flux
which is applied t o all pins of the f lat pack-IC, you
can remove it easily. (Fig. S-1-3)
Flat Pack-IC
Desoldering Braid
(4) B ottom of the flat pack-IC is fixed with glue to the
CBA; when removing en tire flat pack-IC, fir st apply
soldering iron to c en ter of the flat pack-IC and hea t
up. Then remove (glue will be melted). (Fig. S-1-6)
(5) R elease the fla t pack-IC from the CBA using twee-
zers. (Fig. S-1-6)
Note:
When using a solde ring iron, care must be taken
to ensure that the flat pack-IC is not being held by
glue. When the flat pack-IC is removed from the
CBA, handle it ge ntl y bec au se it may be damaged
if force is applied.
Soldering Iron
Fig. S-1-3
(2) Lift each lead of the flat pack-IC upward one by
one, using a sharp pin or wire to which sold er will
not adhere (iron wir e). When heating the pi ns, us e
a fine tip soldering iron or a hot air desoldering
machine. (Fig. S-1-4)
Sharp
Pin
Fine Tip
Soldering Iron
Fig. S-1-4
(3)Botto m of the flat pack-IC is fixed with glue to the
CBA; when removing en tire flat pack -IC, first appl y
soldering iron to c ent er of the fla t pa ck - IC an d h eat
up. Then remove (glue will be melted). (Fig. S-1-6)
(4)Relea se th e flat pac k-IC from the CB A us ing twee -
zers. (Fig. S-1-6)
With Iron Wire:
(1)Using desoldering braid, remove the solder from all
pins of the flat pack-IC. W hen you use solder flux
which is applied t o all pins of the f lat pack-IC, you
can remove it easily. (Fig. S-1-3)
(2) Affix the wire to a workbench or solid mounting
point, as shown in Fig. S-1-5.
(3) While heating the pins using a fine tip soldering
iron or hot air blower, pull up t he wir e as t he so lde r
melts so as to lift the IC leads from the CBA contact
pads as shown in Fig. S-1-5
To Solid
Mounting Point
CBA
Tweezers
Hot Air Blower
or
Iron Wire
Soldering Iron
Fig. S-1-5
Fine Tip
Soldering Iron
Flat Pack-IC
Fig. S-1-6
1-3-2 NOTE_1
2. Installation
(1) Using desoldering braid, remove the solder from
the foil of each pi n of the flat pack-IC on the CBA
so you can install a replacemen t flat pack-IC more
easily.
(2)The “ I ” mark on the flat pack -IC indicates pin 1.
(See Fig. S-1-7.) Be sure this mar k matches the 1
on the PCB when positioni ng for installation. Then
presolder the four corn ers o f the fl at pac k -IC. (S ee
Fig. S-1-8.)
(3)Solder all pins of the flat pack-IC. Be sure that none
of the pins have solder bridges.
Example :
Pin 1 of the Flat Pack-IC
is indicated by a " " mark.
Fig. S-1-7
Instructions for Handling
Semi-conductors
Electrostatic breakdown of the semi-conductors may
occur due to a poten tial difference c aused by electrostatic charge during unpacking or repair work.
1. Ground for Human Body
Be sure to wear a gr oundin g band (1MΩ) that is properly grounded to re m ov e an y sta tic el ec tric it y that may
be charged on the body.
2. Ground for Workbench
Be sure to place a c onductive sheet or copper plate
with proper grounding (1MΩ) on the workbench or
other surface, where the semi-conductors are to be
placed. Because t he static electric ity charge on c lothing will not escape through the body grounding band ,
be careful to avoid contacting semi-conductors with
your clothing.
< Incorrect >
CBA
Presolder
Flat Pack-IC
Fig. S-1-8
CBA
< Correct >
Grounding Band
1MΩ
CBA
1MΩ
Conductive Sheet or
Copper Plate
1-3-3 NOTE_1
PREPARATION FOR SERVICING
How to Enter the Service Mode
About Optical Sensors
Caution:
An optical sensor system is used for the Tape Start
and End Sensors on this equipment. Carefully read
and follow the instruct ions below. Otherwise the unit
may operate erratically.
What to do for preparation
Insert a tape into th e Deck Mechanis m Assembly and
press the PLAY button. The tape will be loaded into
the Deck Mechanism Assembly. Make sure the power
is on, TP507 (SENSOR INHIBITION) to GND. This will
stop the function of Tape Start Sensor, Tape End Sensor and Reel Sensors. (If these TPs are connected
before plugging in the unit, th e functi on of th e sens ors
will stay valid.) See Fig. 1.
Because the Tape End Sensors are inactive, do
Note:
not run a tape a ll th e way t o the s tart or t he en d of the
tape to avoid tape damage.
About REC-Safety Switch
Caution:
The REC-Safety Switch is directly mounted on the
Main CBA. When the Dec k Mechanism Assembly is
removed from t he Main CBA for servic ing, this sw itch
does not work automatically.
What to do for preparation
In order to record, pr ess the Rec butt on whil e push ing
REC-SAFETY SW on the Main CBA. See Fig. 1.
Q503
SW506
Q504
TP507
S-INH
(REC-SAFETY SW)
Fig. 1
1-4-1 HC2C0PFS
CABINET DISASSEMBLY INSTRUCTIONS
1. Disassembly Flowchart
This flowchart indicate s the disas sembly step s 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.
[1] Top Case
[2] Front Assembly
[3] VCR Chassis Unit
[4] Jack CBA
[5] Function CBA
[6] Deck Assembly
[7] Main CBA
2. Disassembly Method
REMOVAL
ID/
LOC.
No.
PART
REMOVE/*UNHOOK/
Fig.
UNLOCK/RELEASE/
No.
UNPLUG/DESOLDER
Note
(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. Release Locking Tab (L-3) and remove Screw
(S-2), five Screws (S-3), three Screws (S-4) and
Screw (S-5). Then, slowly lift the VCR Chassis Unit
(Deck Assembly, Function CBA, Jack CBA and
Main CBA) up.
2. When reassembling, solder wire jumpers as shown
in Fig. 5.
3. Before installing the Deck Assembly, be sure to
place the pin of LD-SW on Main CBA as sho wn in
Fig. 6. Then, install the Deck Assemb ly whil e alig ning the hole of Cam Gear with the pin of LD-SW,
the shaft of Cam Gear with the hol e of LD-SW as
shown in Fig. 6.
[1] Top Case 1 7(S-1) -
Front
[2]
Assembly
VCR
[3]
Chassis
Unit
[4] Jack CBA 4 Desolder, (S-6) -
Function
[5]
CBA
Deck
[6]
Assembly
[7] Main CBA 5 ---------- -
↓
(1)
↓
(2)
2 *3(L-1),*4(L-2) -
*(L-3), 5(S-3), 3(S-4),
3
(S-5)
5 Desolder -
5,6 2(S-7), Desolder 2,3
↓
(3)
↓
(4)
1
↓
(5)
1-5-1 HC2C0DC
(S-1)
[1] T op Case
(S-1)
(S-1)
Fig. 1
(S-3)
[3]VCR
Chassis Unit
(S-4)
(S-3)
(S-5)
(S-4)
(S-3)
(L-2)
[2] Front
Assembly
(L-1)
(L-2)
(L-3)
Fig. 3
[4] Jack CBA
(S-6)
Desolder
Fig. 2
Fig. 4
1-5-2 HC2C0DC
FE Head
Cylinder Assembly
AC Head
Assembly
Pin
SW507
LD-SW
[6] Deck Assembly
(S-7)
[5] Function
CBA
Desolder from
bottom
From
FE Head
Lead with
red stripe
From
Cylinder
Assembly
Lead with
white stripe
From
AC Head
Assembly
[7] Main CBA
From
Capstan Motor
Assembly
Lead with
white stripe
(S-7)
[7] Main CBA
[6] Deck Assembly
Shaft
Hole
LD-SW
Cam Gear
Hole
Pin
[7] Main CBA
Fig. 6
TOP VIEW
Lead connections of Deck Assembly and Main CBA
Fig. 5
1-5-3 HC2C0DC
ELECTRICAL ADJUSTMENT INSTRUCTIONS
General Note: "CBA" is an abbreviation for
"Circuit Board Assembly."
NOTE:
1.Electrical adjustments a re required after re placing
circuit component s and certain mechanical parts.
It is important to do these adjustments only afte r
all repairs and replacements have been completed. Also, do not attempt these adjustments
unless the proper equipment is available.
2.To perform these alignment / confirmation procedures, make sure that the tracki ng co ntrol is set in
the center position: P ress eith er "L5??" or "K" button
on the remote control unit first, then the "PLAY"
button (Front Panel only).
Test Equipment Required
1.Oscilloscope: Dual-trace with 10:1 probe,
V-Range: 0.001~50V/Div.,
F-Range: DC~AC-20MHz
2.Alignment Tape (FL6A)
Head Switching Position Adjustment
Purpose:
To determine the Head Switching point during
playback.
Symptom of Misadjustment:
May cause Head Switching noise or ver tical jitter
in the picture.
Test point Adj.Point Mode Input
TP751(V-OUT)
TP502(RF-SW)
GND
Tape
FL6A Oscilloscope
Connections of Measurement Equipment
Main CBA
VR501
(Switching Point)
(MAIN CBA)
Measurement
Equipment
TP751
GND
TP502
PLAY
(SP)
6.5H±1H
(412.7µs±60µs)
Oscilloscope
-----
Spec.
CH1 CH2
Trig. (+)
Figure 1
EXT. Syncronize Trigger Point
V-Sync
CH1
CH2
Reference Notes:
Playback the Alignment tape and adjust VR501 so that
the V-sync front edg e of the CH1 video output waveform is at the 6.5H(412.7µs) delayed position from the
rising edge of the CH2 head switching pulse waveform.
1.0H
Switching Pulse
6.5H
0.5H
1-6-1 HC2C0EA
M
M
LOADING
MOTOR
CYLINDER ASSEMBLY CAPSTAN MOTOR
DRUM
MOTOR
PG
SENSOR
CONTROL
HEAD
CL287
5 5CTL(+)
6 6CTL(-)
CL504
AC HEAD ASSEMBLY
MAIN CBA
KEY- 2
C-FG
C-CONT
D-FG
D-PG
ST-S
T-REEL
C-F/R
KEY- 1
REMOCON-IN
CTL(+)
RESET
REC-SAF-SW
PG-DELAY
CTL(-)
D-V SYNC
D-REC-H
RF-SW
H-A-SW
C-ROTA
END-S
14
90
89
94
95
76
87
10
4
80
34
78
2
13
15
18
65
16
31
8
7
RS501
REMOTE
SENSOR
LM-FWD/REV
81
D-CONT77
(DECK ASSEMBLY)
Servo/System Control Block Diagram
BLOCK DIAGRAMS
T-REEL
Q501
RESET
Q503
S-REEL79
SW-POINT
AL+5V
AL+5V
VR501
TIMER+5V
S-REEL
PS503
TP506
I2C-BUS SDA
I2C-BUS SDA
I2C-BUS SCL
A-MUTE-H
A-MUTE-H
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
REC-SAFETY
TO
VIDEO BLOCK
TO
AUDIO BLOCK
2 2KEY-2
4 4KEY-1
KEY SWITCH
KEY SWITCH
CL505 CN651
FUNCTION CBA
1-7-1 1-7-2 HC341BLS
SDA
SDA
SCL
SCL
TU701(TUNER UNIT)
IC503 (MEMORY)
72
83
I2C-BUS SCL
D-V SYNC
D-REC-H
RF-SW
H-A-SW
C-ROTA
I2C-BUS SDA
H-A-COMP
V-ENV
C-SYNC
I2C-BUS SCL
71
3
5
SDA
SCL
12
11
LD-SW9
AL+15V/+12V
AL+12V
AL+5V
AL+5V
SW507
P-ON+5V
LD-SW
AL+5V
D502
S-LED
END-S
TO
POWER
SUPPLY
BLOCK
KEY
SWITCH
TP507
S-INH
SW505
CH-UP
M
CAPSTAN
MOTOR
IC501
(SERVO/SYSTEM CONTROL)
AUDIO-SW-2
30
AUDIO-SW-1
AUDIO-SW-2
AUDIO-SW-1
29
5
6
CL502
12 C-F/R
11
AL+15V/+12V
10 AL+12V
9
P-ON+5V
8
GND
7
C-FG
6
C-CONT
5
GND
4
D-FG
3
LM-FWD/REV
2
D-CONT
1
D-PG
SENSOR CBA
SENSOR CBA
END-S
ST-S
Q504
Q505
CTL97
FF/REW-L84
Q502
TP501
CTL
Q562
Q563
Q564
Q565
CAS-LED
TIMER-LED
REC-LED 26
25
24
POWER-LED 23
D565 REC
D564 TIMER
D563 CAS
D562 POWER
D561 STAND-BY
SW508
RESET
CYLINDER ASSEMBLY
V(R)-1
V-COM
V(L)-1
CL253
1
2
3
Video Block Diagram
1-7-3 1-7-4 HC341BLV
(DECK ASSEMBLY)
VIDEO (R)-1
HEAD
SP
HEAD
AMP
EP
HEAD
AMP
REC FM
AGC
TO 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
C-SYNC
V-ENV
H-A-COMP
H-A-SW
D-V-SYNC
RF-SW/C-ROTA
VIDEO (L)-1
HEAD
VIDEO (L)-2
HEAD
VIDEO (R)-2
HEAD
V(L)-2
V-COM
V(R)-2
4
5
6
TU701
IC301
(Y/C SIGNAL PROCESS)
IC501 (OSD)
REC-VIDEO SIGNAL PB-VIDEO SIGNAL MODE: SP/REC
SERIAL
DECORDER
V-OUT1
1
V-IN113 3
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
IN2
IN2
AGC
PR
R
Y
C
P
R P R P
EP
Y. DELAY
Y/C
MIX
+
21
7978
AGC VXO
OSD
CHARACTER
MIX
FBC
1/2
58 59
65
2928
69684643
67
84
83
71
62
70
D-REC-H
80
BUFFER
Q101
BUFFER
Q102
TP751
V-OUT
WF1
TU-VIDEO
VIDEO
MAIN CBA
TP502
RF-SW
WF2
Q351
BUFFER
TO SERVO/SYSTEM
CONTROL BLOCK
I2C BUS SDA
I2C BUS SCL
TP301
X301
4.43MHz
C-PB
WF5
Audio Block Diagram
REC
AMP
100
3
AUTO
BIAS
2
1
+5V
+5V
Q401
Q406
BIAS
OSC
Q402
Q404
(PB=ON)
Q405
(PB=ON)
Q403
SWITCHING
D-REC-OFF
5
EQ
AMP
98
7
LINE
AMP
REC-ON
AUDIO HD-SW
CONTROL
MUTE
11
6
PB-ON
SP/LP-ON
P
R
ALC
DET
ALC
IC301 (AUDIO SIGNAL PROCESS)
4 A-PB/REC
CL504
3 A-COM
1 AE-H
2 AE-H/FE-H
A-PB/REC 4
A-COM 3
AE-H 1
AE-H/FE-H 2
CL287
AUDIO
HEAD
AUDIO
ERASE
HEAD
ACE HEAD ASSEMBLY
FE HEAD
2 FE-H
1 FE-H-GND
CL501
1-7-5 1-7-6 HC341BLA
MAIN CBA
PB-AUDIO SIGNAL REC-AUDIO SIGNAL Mode : SP/REC
71
A-MUTE-H
I2C BUS-SCL
I2C BUS-SDA
TO SERVO/SYSTEM
CONTROL BLOCK
FULL
ERASE
HEAD
68 69
SERIAL
DECODER
(DECK ASSEMBLY)
12
16
INV
ATT
TU701
SW
CTL
IC151 (SWITCHING)
PB/EE
PB/EE
PB/EE
PB/EE
TUNER
TU-AUDIO
IN2
IN1
IN1
AUDIO-SW-1
AUDIO-SW-2
TO SERVO/SYSTEM
CONTROL BLOCK
A-IN1
A-OUT1
8
6
JACK CBA
JK101
A-IN1(R)
A-IN1(L)
2
6
1
3
CL101
A-OUT1(R)
A-OUT1(L)
A-IN2
A-OUT2
8
6
8
6
8
6
JK102
A-IN2(R)
A-IN2(L)
2
6
1
3
CL102
CL151
CL152
A-OUT2(R)
A-OUT2(L)
21
1
5
2
4
12
14
15
11
10
9
3
13
TUNER
IN2
IN1
15
13
17
BUFFER
Q151
BUFFER
Q152
2
4
16
6
7
Power Supply Block Diagram
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.
HC341BLP
1-7-7 1-7-8
COLD
MAIN CBA
HOT CIRCUIT. BE CAREFUL.
HOT
IC001
ERROR
VOLTAGE DET
Q002
Q003
Q001
F001
L003
LINE
FILTER
BRIDGE
RECTIFIER
D001 - D004
1
2
3
4
Q004
(SHUNT REGULATOR)
REG
AC001
T001
P-ON+44V
12
P-ON-H
AL+15V/+12V
AL+12V
C-POW-SW
AL+5V
TIMER+5V
P-ON+5V
P-DOWN-L
AL-5V
Q051
Q054
Q056
Q052
Q057
Q058
13
15
14
11
17
18
T1.6A L 250V
FUNCTION INDICATOR SYMBOLS
Note:
The following symb ols wi ll ap pea r on t he i nd ic ato r panel to indicate the c ur rent mode or operatio n of the VCR.
On-screen modes will also be momentarily displayed on the tv screen when you press the operation buttons.
Display panel
RECFUNCTIONSTANDBY TAPE IN TIMER
" H "= LED Light on, " L "= LED Light off
Led Mode Indicator Active
STANDBY Power on = " H "
Power off = " L "
FUNCTION VCR mode = " H "
TV mode = " L "
TAPE IN
1. When reel and capstan mechanism is
not functioning correctly
2. When tape loading mechanism is not
functioning correctly
3. When cassette loading mechanism is
not functioning correctly
4. When the drum is not working properly
TIMER Timer stand by = " H "
REC REC mode = " H "
Cassette in = " H "
Cassette out = " L "
Cassette in
Cassette in
Cassette in
Cassette in
One touch recording = " H "
Timer recording = " H "
General mode = " L "
REC pause
General mode = " L "
Blinks at 0.8Hz interval
Blinks at 1.6Hz interval
Blinks at 3.2Hz interval
Blinks at 6.4Hz interval
Blinks at 0.8Hz interval
1-7-9 HC341FIS
SCHEMATIC DIAGRAMS / CBA’S AND TEST POINTS
Standard Notes
WARNING
Many electrical and mechanical parts in this chassis
have special characteristics. These characteristics
often pass unnoticed and the protection afforded by
them cannot necessarily be obtained by using replacement components rated for higher voltage, wattage,
etc. Replacement p arts that ha ve these special safety
characteristics are identified in this manual and its
supplements; ele ctrical components having such features are identified by the mark " ! " in the schematic
diagram and the parts list. Before replacing any of
these components, read the parts list in this manual
carefully. The use of substit ute replaceme nt parts that
do not have the same s afety character istics as specified in the parts list may create shock, fire, or other
hazards.
Capacitor Temperature Markings
Mark
Capacity
change rate
Standard
temperature
Temperature
range
Notes:
1. Do not use the part number shown on these dr awings for ordering. The correct part number is shown
in the parts list, and may be slightly different or
amended since these drawings were prepared.
2. All resistance values are indicated in ohms
3
(K=10
3. Resistor wattages are 1/4W or 1/6W unless otherwise specified.
4. All capacitance va lue s ar e indicated in µF
(P=10
5. All voltages are DC voltages unless otherwise
specified.
6. Electrical parts such as capacitors, connectors,
diodes, IC’s, transistors, resistors, switches, and
fuses are identi fied by four di gits. The fir st two digits are not shown for each component. In each
block of the diagram, there is a note such as shown
below to indicate these abbreviated two digits.
, M=106).
-6
µF).
(B)
(F) +30 - 80% 20°C -25~+85°C
(SR)
(Z) +30 - 80% 20°C -10~+70°C
Capacitors and transistors are represented by the following symbols.
±
±
10%
15%
20°C -25~+85°C
20°C -25~+85°C
CBA Symbols
(Top View) (Bottom View)
+
Electrolytic Capacitor
(Bottom View)
Transistor or Digital Transistor
E C B
(Top View)
(Top View)
Schematic Diagram Symbols
Digital Transistor
NPN Transistor
E C B
(Top View)
NPN Digital Transistor
E C B
PNP Transistor
E C B
(Top View)
PNP Digital
Transistor
E C B
1-8-1 SCPA1
LIST OF CAUTION, NOTES, AND SYMBOLS USED IN THE SCHEMATIC DIAGRAMS ON THE FOLLOWING
PAGES:
1.
CAUTION:
FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, REPLACE ONLY WITH THE SAME TYPE FUSE.
2.
CAUTION:
Fixed Voltage (or Auto voltage selectable) power supply circuit is used in this unit.
If Main Fuse (F001) is blown, first 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.
3.
Note:
(1) Do not use the part number shown on the drawings for ordering. The correct part number is shown in the parts
list, and may be slightly different or amended since the drawings were prepared.
(2) To maintain origi nal function and reliability of rep aired units, use only original replacement parts which are
listed with their part numbers in the parts list section of the service manual.
4. 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).
5. Mode: SP/REC
6. Voltage indications for PLAY and REC modes on the schematics are as shown below:
Unit: Volts
The same voltage for
both PLAY & REC modes
7. How to read converged lines
1-D3
Distinction Area
Line Number
(1 to 3 digits)
Examples:
1. "1-D3" means that line number "1" goes to area "D3".
2. "1-B1" means that line number "1" goes to area "B1".
8. 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.
5.0
231
5.0
PLAY mode
REC mode
(2.5)
Indicates that the voltage
is not consistent here.
3
AREA D3
2
1
AREA B1
1-D3
ABCD
1-B1
: Used to indicate a test point with no test pin.
: Used to indicate a test point with a test pin.
1-8-2 SCRK05
1-8-3 1-8-4 1-8-5
HC341SCM1
Main 1/4 Schematic Diagram
Note:
When it is necessary to replace one or more of the following Diodes,
all five should be replaced: D561, D562, D563, D564, D565.
*
1
1-8-6 1-8-7 1-8-8 HC341SCM2
Main 2/4 Schematic Diagram
1-8-9
1-8-10
1-8-11
HC341SCM3
Main 3/4 Schematic Diagram
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