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SERVICE MANUAL
VIDEO CASSETTE RECORDER
HR-S3900U/U(C), HR-S5900U/U(C)
HR-S3900U/S5900U
CABLE/ MBR SET
TV DBS A/B
POWER
TV/VCR A. MONITOR DISPLAY
1 2 3
2
4 5 6
DBS DAILY(M-F) WEEKLY
7 8 9
C.RESET AUX
CANCEL 0 TIMER 4
START STOP DATE CH
EXPRESS PROGRAMMING
1 PROG PROG SP/EP SKIP SEARCH
CHECK REW FF
PLAY
REW FF PLAY
STOP PAUSE
POWER +
REC
3 OK
MENU TV CH + CH /+
PUSH / TURN
SHUTTLE
PLUS
TV
+
O
REC LINK A.DUB
L
V
O
L V
TV
S VIDEO VIDEO (MONO)L--AUDIO--R 24HR QUICK
TV CH
PROGRAM
SP EP
S-VHS ET VCR INSERT REC PAUSE STOP/EJECT
MULTI BRAND
REMOTE CONTROL UNIT
SPECIFICATIONS (The specifications shown pertain specifically to the model HR-S3900U/S3910U/S5900U/S5910U)
GENERAL TUNER
Power requirement : AC 120 V` , 60 Hz Tuning system : Frequency-synthesized tuner
Power consumption Channel coverage
Power on : 20 W VHF : Channels 213
JVC SERVICE & ENGINEERING COMPANY OF AMERICA Power off
Temperature
: 2.5 W UHF
CATV
: Channels 1469
: 113 Channels
DIVISION OF JVC AMERICAS CORP. Operating
Storage
: 5°C to 40°C (41°F to 104°F)
: 20°C to 60°C (4°F to140°F)
RF output : Channel 3 or 4 (switchable; preset
to Channel 3 when shipped) 75
Operating position : Horizontal only ohms, unbalanced
Head office : 1700 Valley Road Wayne, New Jersey 07470-9976 (973)315-5000 Dimensions (W x H x D) : 400 x 94 x 283 mm TIMER
East Coast : 10 New Maple Avenue Pine Brook, New Jersey 07058-9641 (973)396-1000 Weight : 3.3 kg Clock reference : Quartz
Midwest : 705 Enterprise Street Aurora, Illinois 60504-8149 (630)851-7855 Format : S-VHS/VHS NTSC standard Program capacity : 1-year programmable timer/
West Coast : 5665 Corporate Avenue Cypress, California 90630-0024 (714)229-8011 Maximum recording time 8 programs
Atlanta : 1500 Lakes Parkway Lawrenceville, Georgia 30043-5857 (770)339-2582 SP : 210 min. with ST-210 video cassette Memory backup for timer is not supported.
: 2969 Mapunapuna Place Honolulu, Hawaii 96819-2040 (808)833-5828 EP : 630 min. with ST-210 video cassette
Hawaii
ACCESSORIES
VIDEO/AUDIO
Provided accessories : Infrared remote control unit, "AA"
Signal system : NTSC-type color signal and EIA battery x 2,
monochrome signal, 525 lines/60 fields S-video cable (4-pin),
Recording/ RF cable (F-type)
Playback system : DA-4 (Double Azimuth) head helical
JVC CANADA INC. Signal-to-noise ratio
scan system
: 45 dB
Specifications shown are for SP mode unless specified otherwise.
E. & O.E. Design and specifications subject to change without notice.
Head office : 21 Finchdene Square Scarborough, Ontario M1X 1A7 (416)293-1311 Horizontal resolution
Montreal : 16800 Rte Trans-Canadienne, Kirkland, Quebec H9H 5G7 (514)871-1311 VHS : 230 lines
S-VHS : 400 lines
Vancouver : 13040 Worster Court Richmond, B.C. V6V 2B3 (604)270-1311
No. 82848
Frequency range
Normal audio : 70 Hz to 10,000 Hz
Hi-Fi audio : 20 Hz to 20,000 Hz
Input/Output : RCA connectors (IN x 2, OUT x 1)
S-video connectors
For HR-S5900U/5910U: (IN x 2, OUT x 1)
S40895-03 For HR-S3900U/3910U: (IN x 1, OUT x 1)
Printed in Japan This service manual is printed on 100% recycled paper. No. 82848
COPYRIGHT © 2001 VICTOR COMPANY OF JAPAN, LTD. March 2001
TABLE OF CONTENTS
Section Title Page Section Title Page
Important Safety Precautions 3. ELECTRICAL ADJUSTMENT
INSTRUCTIONS 3.1 Precaution ............................................................................ 3-1
3.1.1 Required test equipments ............................................... 3-1
1. DISASSEMBLY 3.1.2 Required adjustment tools .............................................. 3-1
1.1 Disassembly flow chart ........................................................ 1-1 3.1.3 Color (colour) bar signal,Color (colour) bar pattern .......... 3-1
1.2 How to read the disassembly and assembly ........................ 1-1 3.1.4 Switch settings and standard precautions ...................... 3-1
3.1.5 EVR Adjustment .............................................................. 3-1
1.3 Disassembly/assembly method ........................................... 1-1
3.2 Servo circuit ............................................................................ 3-2
1.4 Service position .................................................................... 1-4
3.2.1 Switching point ................................................................ 3-2
1.4.1 How to set the "Service position" .................................. 1-4 3.2.2 Slow tracking preset ........................................................ 3-2
1.5 Mechanism service mode .................................................... 1-4 3.3 Video circuit .......................................................................... 3-2
1.5.1 How to set the "Mechanism service mode" .................. 1-4 3.3.1 D/A level .......................................................................... 3-2
1.6 Jig RCU mode ....................................................................... 1-4 3.3.2 EE Y/PB Y (S-VHS/VHS) level .......................................... 3-2
1.6.1 Setting the Jig RCU mode ............................................... 1-4 3.3.3 REC color (colour) level ................................................... 3-3
1.6.2 Setting the User RCU mode ............................................ 1-4 3.3.4 Video EQ (Frequency response) ...................................... 3-3
1.7 Emergency display function ................................................. 1-5 3.3.5 Auto picture initial setting ................................................ 3-4
1.7.1 Displaying the EMG information ..................................... 1-5 3.4 Audio circuit .......................................................................... 3-4
1.7.2 Clearing the EMG history ................................................ 1-5 3.4.1 Audio REC FM ................................................................. 3-4
1.7.3 EMG content description ................................................ 1-6
3.5 Demodulator circuit .............................................................. 3-4
1.7.4 EMG detail information <1> ............................................ 1-7
3.5.1 Input level ........................................................................ 3-4
1.7.5 EMG detail information <2> ............................................ 1-8
3.5.2 Stereo VCO ..................................................................... 3-5
3.5.3 Stereo filter ...................................................................... 3-5
2. MECHANISM ADJUSTMENT 3.5.4 Separation - 1 .................................................................. 3-5
2.1 Before starting repair and adjustment ................................... 2-1 3.5.5 Separation - 2 .................................................................. 3-5
2.1.1 Precautions ...................................................................... 2-1 3.5.6 SAP VCO ......................................................................... 3-6
2.1.2 Checking for proper mechanical operations .................... 2-1
2.1.3 Manually removing the cassette tape ............................. 2-1
2.1.4 Jigs and tools required for adjustment ............................ 2-2 4. CHARTS AND DIAGRAMS
2.1.5 Maintenance and inspection ........................................... 2-3 NOTES OF SCHEMATIC DIAGRAM ............................................ 4-1
2.2 Replacement of major parts ................................................. 2-6 CIRCUIT BOARD NOTES ............................................................. 4-2
2.2.1 Before starting disassembling (Phase matching between 4.1 BOARD INTERCONNECTIONS ............................................ 4-3
mechanical parts) ............................................................ 2-6 4.2 MAIN (VIDEO/AUDIO) SCHEMATIC DIAGRAM ................... 4-5
2.2.2 How to set the "Mechanism assembling mode" ........... 2-6 4.3 MAIN (S-SUB) SCHEMATIC DIAGRAM ............................... 4-7
2.2.3 Cassette holder assembly ............................................... 2-6 4.4 MAIN (SYSCON) SCHEMATIC DIAGAM .............................. 4-9
2.2.4 Pinch roller arm assembly ............................................... 2-8 4.5 MAIN (SW.REG) SCHEMATIC DIAGRAM .......................... 4-11
2.2.5 Guide arm assembly and press lever assembly .............. 2-8 4.6 MAIN (TUNER/DEMOD) SCHEMATIC DIAGRAM ............. 4-13
2.2.6 A/C head .......................................................................... 2-8 4.7 MAIN (FRONT) AND ADV. JOG SCHEMATIC DIAGRAMS 4-15
2.2.7 Loading motor ................................................................. 2-8
2.2.8 Capstan motor ................................................................. 2-9 4.8 MAIN (TERMINAL) SCHEMATIC DIAGRAM ...................... 4-17
2.2.9 Pole base assembly (supply or take-up side) ................... 2-9 4.9 MAIN (BS CONNECTION), S-JACK, R.PAUSE AND C.BOX CTL
2.2.10 Rotary encoder ........................................................... 2-10 SCHEMATIC DIAGRAMS .......................................................... 4-19
2.2.11 Clutch unit ................................................................... 2-10 4.10 2D DIGITAL SCHEMATIC DIAGRAM ............................... 4-21
2.2.12 Change lever assembly, direct gear, clutch gear and 4.11 DEMODULATOR SCHEMATIC DIAGRAM ...................... 4-23
coupling gear .............................................................. 2-10 4.12 MAIN, R.PAUSE AND C.BOX CTL CIRCUIT BOARDS .... 4-25
2.2.13 Link lever .................................................................... 2-11 4.13 2D DIGITAL AND DEMODULATOR CIRCUIT BOARDS .. 4-28
2.2.14 Cassette gear, control cam and worm gear ................ 2-11 4.14 REMOTE CONTROLLER SCHEMATIC DIAGRAM .......... 4-29
2.2.15 Control plate ............................................................... 2-11 4.15 FDP GRID ASSIGNMENT AND ANODE CONNECTION .. 4-30
2.2.16 Loading arm gear (supply or take-up side) and 4.16 WAVEFORMS .................................................................. 4-31
loading arm gear shaft ................................................ 2-12 4.17 VOLTAGE CHARTS .......................................................... 4-33
2.2.17 Take-up lever, take-up head and control plate guide ... 2-13 4.18 CPU PIN FUNCTION ........................................................ 4-34
2.2.18 Capstan brake assembly ............................................. 2-13 4.19 SYSTEM CONTROL BLOCK DIAGRAM .......................... 4-35
2.2.19 Sub brake assembly (take-up side) ............................. 2-13 4.20 VIDEO BLOCK DIAGRAM ............................................... 4-37
2.2.20 Main brake assembly (take-up side), reel disk (take-up side) and 4.21 AUDIO BLOCK DIAGRAM ............................................... 4-41
main brake assembly (supply side) ............................................ 2-13
2.2.21 Tension brake assembly, reel disk (supply side) and
tension arm assembly ................................................. 2-14 5. PARTS LIST
2.2.22 Idler lever, idler arm assembly .................................... 2-14 5.1 PACKING AND ACCESSORY ASSEMBLY ................ 5-1
2.2.23 Stator assembly .......................................................... 2-14 5.2 FINAL ASSEMBLY .................................................... 5-2
2.2.24 Rotor assembly ........................................................... 2-14 5.3 MECHANISM ASSEMBLY ....................................... 5-4
2.2.25 Upper drum assembly ................................................ 2-15 5.4 ELECTRICAL PARTS LIST .................................................... 5-6
2.3 Compatibility adjustment .................................................... 2-16 MAIN BOARD ASSEMBLY <03> .............................................. 5-6
2.3.1 FM waveform linearity .................................................. 2-16 2D DIGITAL BOARD ASSEMBLY <05> .................................. 5-12
2.3.2 Height and tilt of the A/C head ...................................... 2-17 A/C HEAD BOARD ASSEMBLY <12> ..................................... 5-13
2.3.3 A/C head phase (X-value) ............................................... 2-17 DEMOD BOARD ASSEMBLY <14> ........................................ 5-13
2.3.4 Standard tracking preset ............................................... 2-18 S JACK BOARD ASSEMBLY(S5900U/U(C))<36> .................... 5-13
2.3.5 Tension pole position ..................................................... 2-18 ADV.JOG BOARD ASSEMBLY <38> ...................................... 5-13
LOADING MOTOR BOARD ASSEMBLY <55> ....................... 5-14
R.PAUSE BOARD ASSEMBLY <91> ....................................... 5-14
C.BOX BOARD ASSEMBLY <92> ........................................... 5-14
The following table lists the differing points between Models ( HR-S3900U/U(C), HR-S5900U and HR-S5900U(C) ) in this series.
HR-S3900U/U(C) HR-S5900U HR-S5900U(C)
FLYING ERASE HEAD NOT USED USED USED
INSERT/OPERATION NOT USED USED USED
AUDIO DUBBING/OPERATION NOT USED USED USED
REC RESUME NOT USED NOT USED USED
FRONT SOVIDEO INPUT TERMINAL NOT USED USED USED
Important Safety Precautions
Prior to shipment from the factory, JVC products are strictly inspected to conform 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.
· Precautions during Servicing
1. Locations requiring special caution are denoted by labels and in- 12. Crimp type wire connector
scriptions on the cabinet, chassis and certain parts of the product. In such cases as when replacing the power transformer in sets
When performing service, be sure to read and comply with these where the connections between the power cord and power trans-
and other cautionary notices appearing in the operation and serv- former primary lead wires are performed using crimp type connec-
ice manuals. tors, if replacing the connectors is unavoidable, in order to prevent
safety hazards, perform carefully and precisely according to the
2. Parts identified by the ! symbol and shaded ( ) parts are following steps.
critical for safety.
Replace only with specified part numbers. 1) Connector part number : E03830-001
Note: Parts in this category also include those specified to com- 2) Required tool : Connector crimping tool of the proper type which
ply with X-ray emission standards for products using will not damage insulated parts.
cathode ray tubes and those specified for compliance 3) Replacement procedure
with various regulations regarding spurious radiation (1) Remove the old connector by cutting the wires at a point
emission. close to the connector.
Important : Do not reuse a connector (discard it).
3. Fuse replacement caution notice.
Caution for continued protection against fire hazard.
Replace only with same type and rated fuse(s) as specified.
4. Use specified internal wiring. Note especially:
1) Wires covered with PVC tubing
2) Double insulated wires cut close to connector
3) High voltage leads
Fig.3
5. Use specified insulating materials for hazardous live parts. Note
especially: (2) Strip about 15 mm of the insulation from the ends of the
1) Insulation Tape 3) Spacers 5) Barrier wires. If the wires are stranded, twist the strands to avoid
2) PVC tubing 4) Insulation sheets for transistors frayed conductors.
15 mm
6. When replacing AC primary side components (transformers, power
cords, noise blocking capacitors, etc.) wrap ends of wires securely
about the terminals before soldering.
Fig.4
(3) Align the lengths of the wires to be connected. Insert the
wires fully into the connector.
Fig.1 Metal sleeve
7. Observe that wires do not contact heat producing parts (heatsinks,
oxide metal film resistors, fusible resistors, etc.)
8. Check that replaced wires do not contact sharp edged or pointed Connector
parts.
Fig.5
9. When a power cord has been replaced, check that 10-15 kg of
force in any direction will not loosen it. (4) As shown in Fig.6, use the crimping tool to crimp the metal
sleeve at the center position. Be sure to crimp fully to the
complete closure of the tool.
Power cord
1.2
2.0
5 Crimping tool
5.5
Fig.2 Fig.6
10. Also check areas surrounding repaired locations. (5) Check the four points noted in Fig.7.
11. Products using cathode ray tubes (CRTs) Not easily pulled free Crimped at approx. center
In regard to such products, the cathode ray tubes themselves, the of metal sleeve
high voltage circuits, and related circuits are specified for compli-
ance with recognized codes pertaining to X-ray emission.
Consequently, when servicing these products, replace the cath- Conductors extended
ode ray tubes and other parts with only the specified parts. Under
Wire insulation recessed
no circumstances attempt to modify these circuits. more than 4 mm
Unauthorized modification can increase the high voltage value and
cause X-ray emission from the cathode ray tube. Fig.7
I S40888-01
· 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 original positions, Afterwards, perform the following tests and confirm the specified values in order to verify compliance with safety
standards.
1. Insulation resistance test
Confirm the specified insulation resistance or greater between power cord plug prongs and exter-
nally exposed parts of the set (RF terminals, antenna terminals, video and audio input and output
terminals, microphone jacks, earphone jacks, etc.). See table 1 below.
2. Dielectric strength test
Confirm specified dielectric strength or greater between power cord plug prongs and exposed acces-
sible parts of the set (RF terminals, antenna terminals, video and audio input and output terminals,
microphone jacks, earphone jacks, etc.). See table 1 below.
3. Clearance distance
When replacing primary circuit components, confirm specified clearance distance (d), (d') be-
tween soldered terminals, and between terminals and surrounding metallic parts. See table 1
below.
Fig. 8
4. Leakage current test
Confirm specified or lower leakage current between 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.). a b
Measuring Method : (Power ON) Z A c
Insert load Z between earth ground/power cord plug prongs and externally exposed accessible Externally
parts. Use an AC voltmeter to measure across both terminals of load Z. See figure 9 and following exposed V
table 2. accessible part
Fig. 9
5. Grounding (Class 1 model only)
Confirm specified or lower grounding impedance between earth pin in AC inlet and externally exposed accessible parts (Video in, Video out,
Audio in, Audio out or Fixing screw etc.).
Measuring Method:
Connect milli ohm meter between earth pin in AC inlet and exposed accessible parts. See figure 10 and grounding specifications.
Fig. 10
Table 1 Specifications for each region
Table 2 Leakage current specifications for each region
Note: These tables are unofficial and for reference only. Be sure to confirm the precise values for your particular country and locality.
II S40888-01
SECTION 1
DISASSEMBLY
1.1 Disassembly flow chart 1.3 Disassembly/assembly method
This flowchart lists the disassembling steps for the cabinet Step/ Fig.
Loc No. Part Name No. Point Note
parts and P.C. boards in order to gain access to item(s) to
[1] Top cover, D1 3(S1a)
be serviced. When reassembling, perform the step(s) in re- -----------------
Bracket 2(S1b)
verse order. Bend, route and dress the flat cables as they
[2] Front panel assembly D2 CN7001(WR2a)
were originally laid. 7(L2a)
S Jack board CN7108(WR2b),
-----------------
assembly 2(S2a)
[1] Top cover, Bracket
[3] Drum assembly D3 CON1(WR3a),
CN1(WR3b),
[2] Front panel assembly, (S3a), (W3a),
S Jack board assembly Spacer, (S3b), (S3c)
[4] Mechanism assembly D4 CN2001(WR4a),
[3] Drum assembly (S4a), (S4b),
(S4c), (S4d)
[5] Main board assembly D5 (S5a), 7(L5a)
[4] Mechanism assembly
[5] Main board assembly
· When reattaching the Front panel assembly, make sure that
the door opener "a" of the Cassette holder assembly is low-
ered in position prior to the reinstallation.
· When reattaching the Front panel assembly, pay careful at-
1.2 How to read the disassembly and assembly tention to the switch lever not to make it touch the switch
knob "b" of the Main board assembly from the side.
Step/ Fig.
Loc No. Part Name No. Point Note · Be careful not to damage the connector and wire etc. during
[1] Top cover, D1 4(S1a),(S1b),3(L1a), connection and disconnection.
2(SD1a),(P1a),(W1a), When connecting the wire to the connector, be careful with
CN1(WR1a),
Bracket 2(S1c) the wire direction.
· When it is required to remove the screws (S4a to S4b) re-
(1) (2) (3) (4) (5) taining the Mechanism assembly, please refer to the "Pro-
cedures for Lowering the Cassette holder assembly"(See
(1) Order of steps in Procedure on page 1-2).
When reassembling, perform the step(s) in the reverse order. · When reattaching the Mechanism assembly to the Main
These numbers are also used as the identification (location) No. board assembly, take care not to damage the sensors and
of parts Figures. switch on the Main board assembly.
(2) Part name to be removed or installed.
(3) Fig. No. showing procedure or part location.
(4) Identification of part to be removed, unhooked, unlocked,
released, unplugged, unclamped or unsoldered.
P= Spring, W= Washer, S= Screw, L= Locking tab, SD= Solder,
CN**(WR**)= Remove the wire (WR**) from the connector
(CN**).
Note:
· The bracketed ( ) WR of the connector symbol are as-
signed nos. in priority order and do not correspond to
those on the spare parts list.
(5) Adjustment information for installation
1-1
Procedures for Lowering the Cassette holder assembly
As the mechanism of this unit is integrated with the Housing
assembly, the holder must be lowered and the two screws un-
screwed when removing the Mechanism assembly.
[2]
Front panel
assembly
(L2a)
(A)
(B)
Fig. 2
CN7001
(L2a)
Fig. 1
"b"
Front panel (L2a) "a"
back side
CN7108
WR2a
Fig. 3
(S2a)
WR2b
Turn the loading motor pulley in the direction as indicated by S Jack
Fig.2. As both (A) and (B) levers are lodged twice, push the board assembly
levers in the direction as indicated by Fig.3 to release them.
When pushing the levers, do it in the order of (A), (B), (B),
(A). When the holder has been lowered, turn the pulley until
the cassette holder is securely in place without allowing any
up/down movement.
Procedures for Lowering the Cassette holder assembly Fig. D2
Note:
(S1a) When installing the Drum assembly, secure the screws (S3a to
(S1a) S3c) in the order of a, b, c.
Inertia plate
[1] Top cover
(S3a)
(S3c)
WR3a
(L3a) (W3a)
spacer CON1
(P3)
(S3b)
(S1a) (L3b) WR3b
(S1b)
Roller arm
assy
Not used Cleaner assy
(S1b) [3]
Drum
[1] asembly
Bracket (L3c)
Not used
CN1
Fig. D1 Fig. D3
1-2
Note:
When installing the Mechanism assembly, secure the screws
(S4a to S4b) in the order of a, b.
(S5a) [5]
(S4c) Main board
WR4a assembly
(S4a)
(S4d)
(S4b)
[4]
Mechanism
assembly
(L5a)
Q3002
End sensor
CN2001
D3001
LED
S3002
S cassette switch
Fig. D4 Fig. D5
1-3
1.4 Service position TP2253
A.PB.FM
TP106
PB.FM
This unit has been designed so that the Mechanism and
Demodulator
Main board assemblies can be removed together from the board assembly
TP111
D.FF
chassis assembly. Before diagnosing or servicing the cir- TP4001
CTL.P
Main board
cuit boards, take out the major parts from the chassis as- 2D Digital
board assembly
assembly
sembly.
VR1201 CP5302
D/A LEVEL
1.4.1 How to set the "Service position"
(1) Refer to the disassembly procedure and perform the dis- CP4001
assembly of the major parts before removing the Drum TPGND
TP7001
TEST
assembly.
S Jack board assembly
(2) Lower the cassette holder to prepare for the removal of
the Mechanism assembly screws. (Refer to the "Proce-
Fig. 1-4-1a
dures for lowering the Cassette holder assembly" of 1.3
Disassembly/assembly method.)
(3) Remove the combined Mechanism and Main board as- 1.5 Mechanism service mode
semblies. This model has a unique function to enter the mechanism
(4) Connect the wires and connectors of the major parts that into every operation mode without loading of any cassette
have been removed in step (1). (Refer to Fig.1-4-1a.) tape. This function is called the "Mechanism service mode".
(5) Place the combined Mechanism and Main board assem-
blies upside down. 1.5.1 How to set the "Mechanism service mode"
(6) Insert the power cord plug into the power outlet and then (1) Unplug the power cord plug from the power outlet.
proceed with the diagnostics and servicing of the board (2) Connect TPGND and TP7001(TEST) on the Main board
assembly. assembly with a jump wire.
Notes: (3) Insert the power cord plug into the power outlet.
· Before inserting the power cord plug into the power (4) With lock levers (A) (B) on the left and right of the Cas-
outlet, make sure that none of the electrical parts are sette holder assembly pulled toward the front, slide the
able to short-circuit between the workbench and the holder in the same direction as the cassette insertion di-
board assembly. rection. (For the positions of lock levers (A) (B), refer to
· For the disassembly procedure of the major parts and the "Procedures for lowering the Cassette holder assem-
details of the precautions to be taken, see "1.3 Disas- bly" of 1.3 Disassembly/assembly method.)
sembly/assembly method". (5) The cassette holder lowers and, when the loading has
· If there are wire connections from the Main board and completed, the mechanism enters the desired mode.
Mechanism assemblies to the other major parts, be
sure to remove them ( including wires connected to the
major parts ) first before performing step (2). 1.6 Jig RCU mode
· When carrying out diagnosis and repair of the Main
board assembly in the "Service position", be sure to This unit uses the following two modes for receiving remote
ground both the Main board and Mechanism assem- control codes.
blies. If they are improperly grounded, there may be 1) User RCU mode : Ordinary mode for use by the user.
noise on the playback picture or FDP counter display 2) Jig RCU mode : Mode for use in production and serv-
may move even when the mechanism is kept in an in- icing.
operative status.
· In order to diagnose the playback or recording of the When