Some electrical and mechanical parts have special
safety-related characteristics which are often not evident 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 special safety characteristics 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 Product’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 safety and electrical codes of the
countries in which they are to be sold. However, in
order to maintain such compliance, it is equally important to implement the following precautions when a set
is being serviced.
1-1-2 Precautions during Servicing
A. Parts identified by the ! symbol are critical for
safety. Replace only with part number specified.
B. In addition to safety, other parts and assemblies
are specified for conformance with regulations
applying to spurious radiation. These must also be
replaced only with specified replacements.
Examples: RF converters, RF cables, noise blocking capacitors, and noise blocking filters, etc.
C. Use specified internal wiring. Note especially:
1)Wires covered with PVC tubing
2)Double insulated wires
3)High voltage leads
D. Use specified insulating materials for hazardous
live parts. Note especially:
1)Insulation tape
2)PVC tubing
3)Spacers
4)Insulators for transistors
E. When replacing AC primary side components
(transformers, power cord, etc.), wrap ends of
wires securely about the terminals before soldering.
F. Observe that the wires do not contact heat produc-
ing parts (heatsinks, oxide metal film resistors, fusible resistors, etc.).
G. Check that replaced wires do not contact sharp
edges or pointed parts.
H. When a power cord has been replaced, check that
5 - 6 kg of force in any direction will not loosen it.
I. Also check areas surrounding repaired locations.
J. Be careful that foreign objects (screws, solder
droplets, etc.) do not remain inside the set.
K. Crimp type wire connector
The power transformer 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: Do not re-use a connector. (Discard it.)
2)Strip about 15 mm of the insulation from 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 fully to the complete closure of the tool.
L. When connecting or disconnecting the internal con-
nectors, first, disconnect the AC plug from the AC
outlet.
1-1
1-1-3 Safety Check after Servicing
Examine the area surrounding the repaired location for
damage or deterioration. Observe 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 clearance distance (d) and (d’) between soldered terminals, and between terminals and surrounding metallic parts. (See Fig. 1-1-1)
Table 1-1-1 : Ratings for selected area
AC Line VoltageClearance Distance (d) (d’)
Chassis or Secondary Conductor
Primary Circuit Terminals
dd'
230 V
Note: This table is unofficial and for reference only.
Be sure to confirm the precise values.
≥3 mm(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 across the terminals of load
Z. See Fig. 1-1-2 and the following table.
Table 1-1-2: Leakage current ratings for selected areas
AC Line VoltageLoad ZLeakage Current (i)
2kΩ RES.
Connected in parallel
230 V
50kΩ RES.
Connected in parallel
i≤0.7mA AC Peak
i≤2mA DC
i≤0.7mA AC Peak
i≤2mA DC
Fig. 1-1-1
Exposed Accessible Part
Z
One side of
B
Power Cord Plug Prongs
One side of power cord plug
AC Voltmeter
(High Impedance)
Fig. 1-1-2
prongs (B) to:
RF or
Antenna terminals
A/V Input, Output
Note: This table is unofficial and for reference only. Be sure to confirm the precise values.
1-2
1-2 STANDARD NOTES FOR SERVICING
1-2-1 Circuit Board Indications
1. The output pin of the 3 pin Regulator ICs is indicated as shown.
Top View
Input
Out
2. For other ICs, pin 1 and every fifth pin are indicated
as shown.
In
Pin 1
3. The 1st pin of every male connector is indicated as
shown.
Pin 1
Bottom View
5
10
1-2-3 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. 1-2-1)
Fig. 1-2-1
(2) Remove the flat pack-IC with tweezers while apply-
ing the hot air.
(3) Bottom of the flat pack-IC is fixed with glue to the
CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. 1-2-6)
(4) Release the flat pack-IC from the CBA using twee-
zers. (Fig. 1-2-6)
1-2-2 Instructions for Connectors
1. When you connect or disconnect the FFC (Flexible
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 around 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. 1-2-2)
2. The flat pack-IC on the CBA 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. 1-2-2
1-3
With Soldering Iron:
(1) Using desoldering braid, remove the solder from all
pins of the flat pack-IC. When you use solder flux
which is applied to all pins of the flat pack-IC, you
can remove it easily. (Fig. 1-2-3)
Flat Pack-IC
Desoldering Braid
(4) Bottom of the flat pack-IC is fixed with glue to the
CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. 1-2-6)
(5) Release the flat pack-IC from the CBA using twee-
zers. (Fig. 1-2-6)
Note:
When using a soldering 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 gently because it may be damaged
if force is applied.
Soldering Iron
Fig. 1-2-3
(2) Lift each lead of the flat pack-IC upward one by
one, using a sharp pin or wire to which solder will
not adhere (iron wire). When heating the pins, use
a fine tip soldering iron or a hot air desoldering
machine. (Fig. 1-2-4)
Sharp
Pin
Fine Tip
Soldering Iron
Fig. 1-2-4
(3) Bottom of the flat pack-IC is fixed with glue to the
CBA; when removing entire flat pack-IC, first apply
soldering iron to center of the flat pack-IC and heat
up. Then remove (glue will be melted). (Fig. 1-2-6)
(4) Release the flat pack-IC from the CBA using twee-
zers. (Fig. 1-2-6)
With Iron Wire:
(1) Using desoldering braid, remove the solder from all
pins of the flat pack-IC. When you use solder flux
which is applied to all pins of the flat pack-IC, you
can remove it easily. (Fig. 1-2-3)
(2) Affix the wire to a workbench or solid mounting
point, as shown in Fig. 1-2-5.
(3) While heating the pins using a fine tip soldering
iron or hot air blower, pull up the wire as the solder
melts so as to lift the IC leads from the CBA contact
pads as shown in Fig. 1-2-5.
To Solid
Mounting Point
CBA
Tweezers
Hot Air Blower
or
Iron Wire
Soldering Iron
Fig. 1-2-5
Fine Tip
Soldering Iron
Flat Pack-IC
Fig. 1-2-6
1-4
2. Installation
(1) Using desoldering braid, remove the solder from
the foil of each pin of the flat pack-IC on the CBA
so you can install a replacement flat pack-IC more
easily.
(2) The “I” mark on the flat pack-IC indicates pin 1.
(See Fig. 1-2-7.) Be sure this mark matches the 1
on the PCB when positioning for installation. Then
presolder the four corners of the flat pack-IC. (See
Fig. 1-2-8.)
(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. 1-2-7
1-2-4 Instructions for Handling
Semi-conductors
Electrostatic breakdown of the semi-conductors may
occur due to a potential difference caused by electrostatic charge during unpacking or repair work.
1. Ground for Human Body
Be sure to wear a grounding band (1MΩ) that is properly grounded to remove any static electricity that may
be charged on the body.
2. Ground for Workbench
(1) Be sure to place a conductive sheet or copper plate
with proper grounding (1MΩ) on the workbench or
other surface, where the semi-conductors are to be
placed. Because the static electricity charge on
clothing will not escape through the body grounding band, be careful to avoid contacting semi-conductors with your clothing.
Timer indication :24-hour system
Operating temperature :5
Terminals
AERIAL :Coaxial type, male
RF OUT :Coaxial type, female
AUDIO/VIDEO :21 pin scart socket x 2
TV standard
and Two-audio heads
Helical scan system
IRA~IRJ
E21~E69
CATV
(adjustable)
º
C ~ 40ºC
[ VT-MX310E(UK) ]
Electrical Specifications
Video output level :1Vp-p
Video output impedance :75Ω unbalanced
Audio output level :-6dBV
Video input level :0.5 ~2.0Vp-p
Audio input level :-10dBV
Video S/N ratio
(STANDARD):45dB
Audio S/N ratio
(STANDARD):41dB
Other Specifications
Power requirement :220-240V50Hz
Power consumption :20 Watts (Stand by:3.3 watts)
Dimensions :W 360mm
Timer indication :24-hour system
Operating temperature :5
Terminals
AERIAL :Coaxial type, male
RF OUT :Coaxial type, female
AUDIO/VIDEO :21 pin scart socket x 2
TV standard
helical scan system
IRA~IRJ
E21~E69
CATV
(adjustable)
º
C ~ 40ºC
Electrical Specifications
Video output level :1Vp-p
Video output impedance :75
Audio output level :-6dBV
Video input level :0.5 ~2.0Vp-p
Audio input level :-10dBV
Video S/N ratio
(STANDARD):45dB
Audio S/N ratio
(STANDARD):41dB
Ω unbalanced
Other Specifications
Power requirement :220-240V ~ 50Hz
Power consumption :20 Watts (Stand by: 3.3 watts)
Linear Audio Signal ProcessIncluded in IC301←
Main Microcomputer µPM37762MCA-AC8GP(IC501)M37762MCA-1C1GP(IC501)
VCR-EEP ROMBR24C02F-W(IC503)←
Reset--
Loading Motor Drive--
Cylinder/Loading Motor Control--
Power Reset--
VPSLC74793JM-TRM(IC640)-
Audio Output Selector
LA72648M(IC451)
[VT-FX340E(UK)]
TC4052BF(EL)(IC151)
[VT-MX310E(UK)]
LA72646M-A-MPB(IC451)
[VT-FX240EUK]
TC4052BF(EL)(IC151)
[VT-MX210EUK]
2-3
2-3 FUNCTION INDICATOR SYMBOLS
Note:
The following symbols will appear on the indicator panel to indicate the current mode or operation of the VCR.
On-screen modes will also be momentarily displayed on the tv screen when you press the operation buttons.
Display panel
" H "= LED Light on, " L "= LED Light off
LED MODEINDICATOR ACTIVE
CASSETTE "IN"
CASSETTE "OUT"
CLOCK" 88:88ON
POWER ON" PWR."ON
REC" REC "ON
REC PAUSE" REC "Blinks at 0.8Hz interval
T- R E C , O T R
When reel and capstan mechanism is not
functioning correctly
When tape loading mechanism is not functioning correctly
When cassette loading mechanism is not
functioning correctly
When the drum is not working properly
P-ON Power safety detection
" "
" "
" "
" "
" 1 "
" "
" 2 "
" "
" 3 "
" "
" 4 "
" "
" 5 "
ON
OFF
ON
(T-REC OFF,T-REC incomplete
Blinks at 0.8Hz interval)
Blinks at 0.8Hz interval
Blinks at 0.8Hz interval
Blinks at 0.8Hz interval
Blinks at 0.8Hz interval
Blinks at 0.8Hz interval
S-INH conditionAll modesBlinks at 0.8Hz interval
2-4
PWR.REC
10
11
14
12
13
L
o
2-4 OPERATING CONTROLS AND FUNCTIONS
[ VT-FX340E(UK) ]
Front Panel
1. Cassette compartment
2. D (F.FWD) button
3. B (PLAY) button
4. E (REW) button
5. CA( STOP/EJECT) button
6. I (REC) button
7. Indicator (See below)
8. PROGRAM (o/p) [TRACKING]
buttons
9.y (OPERATE) button
10. PWR. (Power) indicator
11. TAPE IN indicator
12. REC indicator
13. (Timer) indicator
14. CLOCK indicator
15. Power cord
16. AV2 (DECODER) socket
17. AV1 (TV) socket
18. RF OUT socket
19. AERIAL socket
Indicator
Rear Panel
15
PROGRAM
TRACKING
1
247
35689
1716
AV2(DECODER)AV1(TV)
AERIAL
RF OUT
Remote Control
OPERATE
1
1
2
4
7
VIDEO Plus+
3
4
MENU
5
6
7
8
REW
REC
QUICK-FIND
9
10
AUDIO
SELECT
2
5
8
0
DISPLAY
PLAY
TO
S
TIME
SEARCH
3
6
9
DAILY/WEEKLY
COUNTER
RESET
P
SPEED
INDEX
EJECT
PROGRAM
SLOW
MEMORY
D
W
.F
F
PAUSE/STILL
22
21
20
19
18
17
16
15
14
13
12
11
1819
1. OPERATE button
2. NUMBER buttons
3. VIDEO Plus+ button
4. MENU button
5. DISPLAY button
6. REW/s button
7. STOP/
8. REC button
9. QUICK-FIND button
10. TIME SEARCH button
11. INDEX SEARCH button
12. PAUSE/STILL button
13. SPEED button
14. F.FWD/B button
15. PLAY/
16. COUNTER RESET button
17. COUNTER MEMORY button
18. SLOW button
19. DAILY/WEEKLY button
20. PROGRAM (o/p) buttons
21. EJECT button
22. AUDIO SELECT button
L
o
button
button
2-5
PWR.REC
10
11
14
12
13
L
o
[ VT-MX310E(UK) ]
Front Panel
PROGRAM
TRACKING
Indicator
Rear Panel
15
1
1. Cassette compartment
2. D (F.FWD) button
3. B (PLAY) button
4. E (REW) button
5.
CA(STOP/EJECT) button
6.
I (
REC) button
7. Indicator (See below)
8. PROGRAM (o/p) [TRACKING]
buttons
9.y (OPERATE) button
247
35689
10. PWR. (Power) indicator
11. TAPE IN indicator
12. REC indicator
13. (Timer) indicator
14. CLOCK indicator
1716
AV2(DECODER)AV1(TV)
15. Power cord
16. AV2 (DECODER) socket
17. AV1 (TV) socket
18. RF OUT socket
19. AERIAL socket
AERIAL
RF OUT
Remote Control
OPERATE
1
2
1
5
2
3
4
4
7
VIDEO Plus+
MENU
8
0
DISPLAY
5
EW
6
7
R
REC
8
DAILY/WEEKLY
PLAY
O
T
S
3
6
9
RESET
P
SPEED
EJECT
PROGRAM
COUNTER
MEMORY
FWD
.
F
PAUSE/STILL
17
16
15
14
13
12
11
10
9
1819
1. OPERATE button
2. NUMBER buttons
3. VIDEO Plus+ button
4. MENU button
5. DISPLAY button
6. REW/s button
7. STOP/
8. REC button
9. PAUSE/STILL button
10. SPEED button
11. F.FWD/ B button
12. PLAY/
13. COUNTER RESET button
14. COUNTER MEMORY button
15. DAILY/WEEKLY button
16. PROGRAM (o/p) buttons
17. EJECT button
L
o
button
button
2-6
3
MAINTENANCE AND INSPECTION
3-1 TROUBLESHOOTING
Troubleshooting is how to service for the specifying malfunction or poor parts.
Detect malfunction or poor parts and service as the following charts.
Video problem 1 (No recording Video)
RF INPUT
Check Video signal at pin 48 of IC301.
OK
Check TU701 and line between
TU701 and pin 48 of IC301, and
service it if detective.
Check Video signal at pin 50 of IC501.
OK
Check Video signal at pin 56 of IC301.
OK
Check IC501 and line between pin
52 of IC501 and pin 56 of IC301, and
service it if detective.
Cleaning the Video Head. (See page 3-7.) Or check Cylinder Assembly and service it if detective.
LINE INPUT (AV2)
NG
NG
LINE INPUT (AV1)
Check Video signal at pin 50 of IC301.
OK
Check A/V cable, JK101 and line
between JK101 and pin 50 of IC301, and
service it if detective.
NG
Check IC301, X301 and line between pin 65 of IC301
and pin 50 of IC501, and service it if detective.
NG
Check Video signal at pin 52 of IC301.
OK
Check Video signal at pin 50 of IC501.
OK
Check Video signal at pin 56 of IC301.
OK
Cleaning the Video Head.(See page 3-7.)
Or check Cylinder Assembly and service it if detective.
NG
Check AV cable, JK102 and line
of IC301,
NG
Check IC301, X301 and
pin 50 of IC501
NG
Check IC501 and line between pin 52 of IC501 and pin
56 of IC301, and service it if detective.
and service it if detective.
, and service it if detective.
between
line between pin 52 of IC301 and
JK102 and pin 52
3-1
Video problem 2 (No playback Video)
Check signal at pin 93 and pin 96 (or pin 87, pin 90) of IC301.
OK
Check Video signal at pin 50 of IC501.
OK
Check IC301, X301 and line between pin
65 of IC301 and pin 50 of IC501, and
service it if detective.
NG
NG
Cleaning the Video Head. (See page 3-7.) Or check
Cylinder Assembly and service it if detective.
Check Video signal at pin 56 of IC301.
OK
RF OUTLINE OUT (AV1)LINE OUT (AV2)
Check Video signal at pin 6 of TU701.
OKOKOK
Check TU701 and service
it if detective.
Check line between pin 52 of IC501
and pin 6 of TU701, and service it if
detective.
NGNG
Check Video signal at pin 19 of JK101.Check Video signal at pin 19 of JK102.
Check JK101 and AV cable,
and service it if detective.
Check line between pin 61 of IC301
and pin 19 of JK101, and service it if
detective.
NG
Check IC501 and line between pin 52 of IC501 and pin
56 of IC301, and service it if detective.
Check JK102 and AV cable,
and service it if detective.
Check line between pin 63 of IC301
and pin 19 of JK102, and service it if
detective.
3-2
Audio problem 1 (No recording Normal Audio)
RF-INPUT
(with VT-FX340E(UK))
Change for Audio-mode(MONO) by AUDIOSELECT KEY of Remote Controller.
OK
Check SIF signal at pin 2 of CN701.
OK
Check Audio signal at pin 4 and 5 of CN701
or pin 4 and 50 of IC451.
OK
Check Audio signal at pin 13, pin 15 or pin 17 of IC301.
OK
Check Tape interchangeability alignment. (See page 5-5.)
OK
Cleaning the Audio Control Head. (See page 3-7.)
LINE INPUT (AV2)
(with VT-FX340E(UK))
Check Audio signal at pin 10 or pin 56 of IC451.
OK
(with VT-MX310E(UK))
NG
NG
(with VT-MX310E(UK))
LINE INPUT (AV1)
Check Audio signal at pin 6 or 52 of IC451.
Check TU701 and
service it if detective.
Check AFV CBA and
service it if detective.
NG
Check IC451 and IC301, and service it if detective.
Check ACE Head Assembly and service it if detective.
NG
Check AV cable, JK102 and line between JK102 and pin
(10, 56) of IC451, and service it if detective.
(with VT-MX310E(UK))
(with VT-FX340E(UK))
OK
Check AV cable, JK101 and
line between JK101 and pin
(6, 52) of IC451, and service
it if detective.
NG
NG
Check Audio signal at pin 17 of IC301.
OK
Check Tape interchangeability alignment. (See page 5-5.)
OK
Cleaning the Audio Control Head. (See page 3-7.)
NG
Check IC451 and IC301, and service it if detective.
NG
Check ACE Head Assembly and service it if detective.
Audio problem 2 (No playback Normal Audio)
(RF OUTPUT/AV1)(AV2)
Check Audio signal at pin 5 of IC301.
NG
Cleaning the Audio
Check Tape interchangeability
alignment. (See page 5-5.)
NG
Check ACE Head Assembly and service it if detective.
Check Audio signal at pin 11 of IC301 or pin 80 of IC451.
OK(with VT-MX310E(UK))
Check Audio signal at pin
(72, 74, 76) of IC451.
NG
Check IC451
it if detective.
and service
OK
Control Head.
(See page 3-7.)
OK(with VT-MX310E(UK))
OK
Check TU701 or
A-OUT jack, and
service it if detective.
Check IC301 and IC451
and service it if detective.
OK
Check Audio signal at pin 5 of IC301.
Check Tape interchangeability
alignment. (See page 5-5.)
Check ACE Head Assembly and service it if detective.
Check Audio signal at pin 11 of IC301 or pin 80 of IC451.
NG
Check Audio signal at pin
65 and pin 67 of IC451.
,
Check IC451
it if detective.
NG
NG
OK(with VT-MX310E(UK))
OK
NG
and service
Cleaning the Audio
OK
Control Head.
(See page 3-7.)
OK(with VT-MX310E(UK))
Check A-OUT jack and
service it if detective.
Check IC301 and IC451
and service it if detective.
OK
NG
,
3-3
Audio problem 3 (No recording Hi-Fi Audio)
RF-INPUT
NGNG
Check SIF signal at pin
2 of CN701.
OK
Check Audio signal at
pin 4 and 5 of CN701 or
pin 4 and 50 of IC451.
OK
Check signal at pin 26 of IC451.
OK
Cleaning the Video Head. (See page 3-7.) Or check Cylinder Assembly and service it if detective.
LINE INPUT (AV2)
Check Audio signal at pin 10 and 56 of IC451.
OK
Check signal at pin 26 of IC451.
OK
Cleaning the Video Head. (See page 3-7.) Or check Cylinder Assembly and service it if detective.
Check TU701 and
service it if detective.
NG
Check AFV CBA and
service it if detective.
NG
NG
NG
LINE INPUT (AV1)
Check Audio signal at
pin 6 and pin 52 of IC451.
OK
Check signal at pin 26 of IC451.
NG
Check IC451 and
service it if detective.
Check AV cable, JK102 and line between JK102 and
pin (10, 56) of IC451, and service it if detective.
Check IC451 and service it if detective.
Check A/V cable, JK101
and line between JK101
and pin (6, 52) of IC451,
and service it if detective.
OK
Cleaning the Video Head.
(See page 3-7.)
NG
Audio problem 4 (No playback Hi-Fi Audio)
(AV1)(AV2)
Check signal at pin 24 and 27 of IC451.
OK
Cleaning the Video Head. (See
page 3-7.) Or check Cylinder
Assembly and service it if detective.
Check Audio signal at pin
74 and pin 76 of IC451.
OK
Check TU701 and A-OUT jack, and service it if detective.
NG
Check IC451 and
service it if detective.
NG
Check signal at pin 24 and pin 27 of IC451.
OK
Cleaning the Video Head. (See
page 3-7.) Or check Cylinder
Assembly and service it if detective.
Check Audio signal at pin
65 and pin 67 of IC451.
OK
NG
Check IC451 and
service it if detective.
NG
3-4
Power problem
It is highly recommended that a variable isolation
transformer which can monitor current be used.
(Alternatively a variable AC source which monitors current will do). Read directions below before
power is added!
1] Check for any defective parts while the secondary
rectifying diodes are disconnected (D011, D013 and
D014) perform a diode check in both forward and
reverse directions through a tester.
2] Remove the following components and check for
defects: snubber diode (D005), switching FET (Q001),
source resistor (R006), control transistor (Q002).
Repair method
CHECK
Connect unit to the isolation transformer and slowly increase the AC supply while monitoring the current, if it
draws too much current (Be ware fuse
is rated for 1.6 amps), then turn off
supply and do repair method #1.
NO
Check whether the primary rectifying
DC of the Switching power supply has
an output. (Reading should be about
168V.)
YES
With the primary DC working check
the secondary 5V.
YES
Are the 44V, 12V and 5V
higher than normal?
NO
Although the secondary 5V is working,
are any of the other voltages higher
than normal (44V and 12V)?
NO
There is no problem on the SW power
supply.
YES
NO
NO
YES
YES
#1
#2
#3
#4
#5
Repair method #2
Check the fuse 1.6A (F001), primary rectifying diodes
(D001-D004) as possible problems. Remove the
above mentioned parts and check them. The circuit
which turns on switching FET (Q001) may be
regarded as a possible cause, even if the load at the
secondary side is shorted, it can't be detected
because switching FET (Q001) isn't operating. Perform check according to the step 1 and 2 of repair
method #1 and check the following parts:
(Remove the part from PCB)
Switching FET (Q001), source resistor (R006), gate
resistor (R008) and start resistor (R003, R004, R005
and R028).
Repair method #3
A circuit to turn on switching FET (Q001) may not work
and this may be regarded as a cause of trouble. Even
if the load at the secondary side is short-circuited, it
cannot be detected because switching FET (Q001)
does not turn on. Therefore, perform check according
to the steps 1] and 2] of the repair method #1 and execute the under-mentioned parts breakage check.
(Remove the part from PCB.)
switching FET (Q001), source resistor (R006), control
transistor (Q002), gate resistor (R008) and start resistor (R003, R004, R005 and R028).
Repair method #4
Repair method #1
(Power must be off)
Short circuit in the secondary side. check diode D014,
D011, D012, D013, switching FET (Q001), control
transistor (Q002), diode (D006), and resistor (R014)
replace as necessary.
Disconnect 44V diode (D011), 12V diode (D013), 5V
diode (D014). Check the load continuity of 44V line,
12V line and 5V line through a tester (resistance
range).
If the tester indicates a lower resistance value around
0 ohm, the line is short-circuited.
Before repairing the switching power supply, find out
the short-circuited area of such line and repair it.
If the tester does not indicate any low resistance value
(around 0 ohm), no load is short-circuited and there is
no problem.
The feedback circuit which is monitored by the output
of voltage may not work and this may be regarded as
a possible cause, remove control transistor Q002 and
check for defects. More over, a photo coupler (IC001)
and transistor (Q004) may be defective, replace any
defective parts with factory originals.
Repair method #5
If the output voltage of the secondary side is slightly
high, the line load may be in the "OPEN" state and this
may be regarded as a cause of trouble. If there is no
output voltage on the secondary side, the rectifying
diodes (D014) and (D015) may be defective.
3-5
3-2 STANDARD MAINTENANCE
3-2-1 Service Schedule of Components
h: Hours : Check I: Change
DeckPeriodic Service Schedule
Ref.No.Part Name1,000 h2,000 h3,000 h4,000 h
B2
B3
B8
B587Tension Lever AssemblyII
B31
B573, B574
B37Capstan MotorII
B52
*B73
B86F Brake Assembly (HI)II
B133
B410Pinch Arm AssemblyII
B414M Brake (SP) Assembly (HI)II
B416
Cylinder Assembly
Loading Motor Assembly
Pulley Assembly (HI)
AC Head Assembly
Reel S, Reel T
Cap Belt
FE Head Assembly
Idler Assembly (HI)
M Brake (TU) Assembly (HI)
II
I
II
I
I
II
I
II
II
B525LDG BeltII
Notes:
1.Clean all parts for the tape transport (Upper Drum with Video Head / Pinch Roller / Audio Control Head / Full
Erase Head) using 90% lsopropyl Alcohol.
2.After cleaning the parts, do all DECK ADJUSTMENTS.
3.For the reference numbers listed above, refer to Deck Exploded Views.
* FE Head Assembly (B73) is used in VT-FX340E(UK) only.
3-6
3-2-2 Cleaning
Cleaning of Video Head
Clean the head with a head cleaning stick or chamois
cloth.
Procedure
1.Remove the top cabinet.
2.Put on a glove (thin type) to avoid touching the
upper and lower drum with your bare hand.
3.Put a few drops of 90% Isopropyl alcohol on the
head cleaning stick or on the chamois cloth and,
by slightly pressing it against the head tip, turn the
upper drum to the right and to the left.
Notes:
1.The video head surface is made of very hard
material, but since it is very thin, avoid cleaning it
vertically.
2.Wait for the cleaned part to dry thoroughly before
operating the unit.
3.Do not reuse a stained head cleaning stick or a
stained chamois cloth.
Cleaning of ACE Head
Clean the head with a cotton swab.
Procedure
1.Remove the top cabinet.
2.Dip the cotton swab in 90% Isopropyl alcohol and
clean the ACE head. Be careful not to damage the
upper drum and other tape running parts.
Notes:
1.Avoid cleaning the ACE head vertically.
2.Wait for the cleaned part to dry thoroughly before
operating the unit or damage may occur.
ACE Head
Upper
Cylinder
Do Not !
Video Head
Cleaning Stick
3-7
4
DISASSEMBLY
4-1 CABINET DISASSEMBLY INSTRUCTIONS
4-1-1 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.
[1] Top Case
[2] Front Assembly
[3] VCR Chassis Unit
[4] Jack CBA
[5] Deck Assembly
[6] Main CBA
[7] AFV CBA
[VT-FX340E(UK)]
[8] Cylinder Shield
4-1-2. Disassembly Method
REMOVAL
ID/
LOC.
No.
PAR T
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. Remove five Screws (S-2), two Screws (S-3) and
Screw (S-4). Then, slowly lift the VCR Chassis Unit
(Deck Assembly, Jack CBA and Main CBA) up.
2. When reassembling, solder wire jumpers as shown
in Fig. 4-1-5.
3. Before installing the Deck Assembly, be sure to
place the pin of LD-SW on Main CBA as shown in
Fig. 4-1-6. Then, install the Deck Assembly while
aligning the hole of Cam Gear with the pin of LDSW, the shaft of Cam Gear with the hole of LD-SW
as shown in Fig. 4-1-6.
[1]Top Case4-1-17(S-1)-
Front
[2]
Assembly
VCR Chas-
[3]
sis Unit
[4]Jack CBA4-1-4Desolder, (S-5)-
Deck
[5]
Assembly
[6]Main CBA4-1-5-----------
AFV CBA
[7]
[VT-FX340E(UK)]
Cylinder
[8]
Shield
↓
(1)
↓
(2)
4-1-2*3(L-1),*4(L-2)-
4-1-35(S-2), 2(S-3), (S-4),1
4-1-5
4-1-6
4-1-5-----------
4-1-52(S-7)-
2(S-6), Desolder2,3
↓
(3)
↓
(4)
↓
(5)
4-1
(S-1)
(S-5)
[4] Jack CBA
Desolder
[1] Top Case
(S-1)
(S-1)
Fig. 4-1-1
(S-2)
[3]VCR
Chassis Unit
(S-2)
(S-3)
(S-2)
(S-4)
(S-3)
(S-2)
(L-2)
[2] Front
Assembly
(L-2)
Fig. 4-1-3
(L-1)
Fig. 4-1-2
Fig. 4-1-4
4-2
[8] Cylinder Shield
FE Head
Cylinder Assembly
(S-7)
Pin
[5] Deck Assembly
[7] AFV CBA
[VT-FX340E(UK)]
Desolder from
bottom
From
From
FE Head
Cylinder
Assembly
(S-6)
TOP VIEW
From
ACE Head
Assembly
ACE Head
Assembly
[6] Main CBA
(S-6)
From
Capstan Motor
Assembly
Lead with
blue stripe
[6] Main CBA
[5] Deck Assembly
Shaft
Hole
LD-SW
SW507
LD-SW
Cam Gear
Hole
Pin
[6] Main CBA
Fig. 4-1-6
Printing
Lead with
blue stripe
Lead connections of Deck Assembly and Main CBA
Lead with
blue stripe
Desolder
from bottom
side
Fig. 4-1-5
4-3
4-2 DISASSEMBLY/ASSEMBLY PROCEDURES OF DECK
MECHANISM
Before following the procedures described below, be sure to remove the deck assembly from the cabinet. (Refer to
CABINET DISASSEMBLY INSTRUCTIONS on page 4-1.)
All the following procedures, including those for adjustment and replacement of parts, should be done in Eject
mode; see the positions of [44] and [45] in Fig. 4-2-1 on page 4-6. When reassembling, follow the steps in reverse
order.