JVC HR-S3800U Service Manual

JVC HR-S3800U Service Manual

Hide thumbs Also See for HR-S3800U:
Table of Contents

Advertisement

SERVICE MANUAL
VIDEO CASSETTE RECORDER
HR-S3800U/S4800U
TV
C.RESET
CANCEL
START
1
PROG
SPECIFICATIONS
GENERAL
Power requirement
: AC 120 V`, 60 Hz
Power consumption
Power on
: 20 W
Power off
: 2.5 W
Temperature
Operating
: 5°C to 40°C (41°F to 104°F)
Storage
: –20°C to 60°C (–4°F to140°F)
Operating position
: Horizontal only
Dimensions (W x H x D) : 400 x 94 x 281 mm
(15-3/4" x 3-3/4" x 11-1/8")
Weight
: 3.4 kg (7.5 lbs)
Format
: S-VHS/VHS NTSC standard
Maximum recording time
SP
: 210 min. with ST-210 video cassette
EP
: 630 min. with ST-210 video cassette
VIDEO/AUDIO
Signal system
: NTSC-type color signal and EIA
monochrome signal, 525 lines/60
fields
Recording/Playback
system
: DA-4 (Double Azimuth) head
helical scan system
Signal-to-noise ratio
: 45 dB
Horizontal resolution
VHS
: 230 lines
S-VHS
: 400 lines
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 (IN x 2, OUT x 1)
CABLE/
MBR SET
DBS
A/B
POWER
TV/VCR
A. MONITOR
DISPLAY
1
2
3
2
4
5
6
DBS
DAILY(M-F)
WEEKLY
7
8
9
AUX
0
TIMER
4
STOP
DATE
CH
EXPRESS PROGRAMMING
PROG
SP/EP
SKIP SEARCH
CHECK
PLAY
POWER
STOP
C
SHUTTLE
PLUS
S-VIDEO
VIDEO (MONO)L—AUDIO—R
S-VHS ET
MULTI BRAND
REMOTE CONTROL UNIT
This service manual is made from all recycled paper.
COPYRIGHT © 2000 VICTOR COMPANY OF JAPAN, LTD.
REW
FF
MENU
PLAY
SP EP
CH
VCR
REC
STOP/EJECT
PAUSE
OK
TUNER
Tuning system
Channel coverage
VHF
UHF
CATV
RF output
TIMER
Clock reference
Program capacity
Memory backup time
ACCESSORIES
Provided accessories
FOR HR-S4800U : Infrared remote control unit,
FOR HR-S3800U : Infrared remote control unit,
Specifications shown are for SP mode unless specified otherwise.
E. & O.E. Design and specifications subject to change without notice.
: Frequency-synthesized tuner
: Channels 2–13
: Channels 14–69
: 113 Channels
: Channel 3 or 4 (switchable;
preset to Channel 3 when
shipped) 75 ohms, unbalanced
: Quartz
: 1-year programmable timer/8 programs
: Approx. 3 min.
"AA" battery x 2,
Audio/video cable,
S-video cable (4-pin),
S-VHS ET labels,
Controller
"AA" battery x 2,
Audio/video cable,
S-video cable (4-pin),
S-VHS ET labels,
No. 82792
March 2000

Advertisement

Table of Contents
loading

Summary of Contents for JVC HR-S3800U

  • Page 1 : DA-4 (Double Azimuth) head S-VHS ET labels, helical scan system Controller Signal-to-noise ratio : 45 dB FOR HR-S3800U : Infrared remote control unit, Horizontal resolution “AA” battery x 2, : 230 lines Audio/video cable, S-VHS : 400 lines...
  • Page 2: Table Of Contents

    3. ELECTRICAL ADJUSTMENT SHUTTLE BOARD ASSEMBLY <85> ........5-14 3.1 PRECAUTION ..............3-1 C.BOX BOARD ASSEMBLY <92> ........... 5-14 The following table lists the differing points between Models ( HR-S3800U/U(C) and HR-S4800U(C) ) in this series. HR-S3800U/U(C) HR-S4800U/U(C) FLYING ERASE HEAD...
  • Page 3: Important Safety Precautions

    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.
  • Page 4 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 compli- ance with safety standards.
  • Page 5 (S1) (L3) (S1) FOIL SIDE <NOTE 3c> CN7001 (L3) <NOTE 3b> (L3) <NOTE 3a> (S1) FRONT PANEL SUPPORTING BACK SIDE TAPE SIDE WR3a <NOTE 3c> CN7108 (S3) WR3b S JACK board assembly Fig. D3 NOTE: When installing the DRUM assembly, secure the screws (S4a) in the order of a , b , c .
  • Page 6 NOTE: When installing the Mechanism assembly, secure the screws (S5a) in the order of a , b . (S6) (S5a) (S5b) <NOTE 5a> (S5c) FOIL SIDE <NOTE 3c> CN7001 Q3002 End sensor (L5) (L6) <NOTE 5c> Spacer <NOTE 5b> (L5) Spacer <NOTE 5b>...
  • Page 7: Disassembly/Assembly Method

    1.4 SERVICE POSITION In order to facilitate diagnosis and the repair of the Mecha- nism assembly, this unit is constructed so as to allow the Mechanism and Main board assemblies to be removed to- JACK board assembly gether from the Bottom chassis assembly. CN7108 1.4.1 How to take out the Mechanism and Main board assemblies...
  • Page 8: Mechanism Service Mode

    MAIN BOARD ASSEMBLY <03> Fig. 1-4-3 1.5.1 How to set the "MECHANISM SERVICE MODE" 1.5 MECHANISM SERVICE MODE (1) Disconnect VCR from AC. This model has a unique function to enter the mechanism (2) Connect TPGND and TP7001(TEST) on the Main board into every operation mode without loading of any cassette assembly with a jump wire.
  • Page 9: Emergency Display Function

    1.6.1 Displaying the emergency information 1.6 EMERGENCY DISPLAY FUNCTION (1) Transmit the code “59” from the Jig RCU. The FDP shows the emergency content in the form of This unit has a function for storing the history of the past “E: : ** ”.
  • Page 10: Emergency Content Description

    1.6.3 Emergency content description NOTE: Emergency contents “E08/E09” are for the model with Dynamic Drum (DD). CONTENT CAUSE 1 The mechanism is locked in the middle of mode transition. E01: Loading EMG When the mechanism mode cannot be changed to an- 2 The mechanism is locked at the loading end due to the encoder position other mode even when the loading motor has rotated for more than 4 seconds in the loading direction, [E:01]...
  • Page 11 1.6.4 Emergency detail information [FDP display] The status (electrical operation mode) of the VCR and the status (mechanism operation mode/sensor information) of the mechanism in the latest emergency can be confirmed 1 : Deck operation mode at the moment of emer- based on the figure in EMG detail information gency 2 : Mechanism operation mode at the moment of...
  • Page 12 1.6.5 Emergency detail information The type of the cassette tape and the cassette tape wind- 6 : Cassette tape winding position ing position can be confirmed based on the figure in EMG The cassette tape winding position at the moment of EMG detail information is displayed by dividing the entire tape (from the beginning [FDP display]...
  • Page 13: Syscon Circuit

    1.7 SYSCON CIRCUIT 1.7.1 Syscon CPU pin function (IC3001) PIN NO. LABEL IN/OUT FUNCTION SP_FG DETECTION SIGNAL FOR SUPPLY REEL ROTATION/TAPE REMAIN TU_FG DETECTION SIGNAL FOR TAKE-UP REEL ROTATION/TAPE REMAIN PAUSE/COMPU_IN REMOTE PAUSE INPUT/NC BS_ANT_ON(H) REMOTE CONTROL DATA INPUT OPE_SW TU_CLK CLOCK FOR DATA TRANSFER TO THE TUNER UNIT TU_DATA...
  • Page 14 PIN NO. LABEL IN/OUT FUNCTION VDD2 SYSTEM POWER AFCC FILTER INPUT FOR HORIZONTAL SYNCHRONIZING OF OSD CHARACTER AFCLPF FILTER INPUT FOR HORIZONTAL SYNCHRONIZING OF OSD CHARACTER FSCI/BIT_IN(H) FSCLPF/BS_P.CTL I2C_DATA IN/OUT I/O DATA FOR MEMORY IC I2C_CLK/TEST SERIAL DATA TRANSFER CLOCK FOR MEMORY IC CHARAE OSD CHARACTER DATA (FRINGE) OUTPUT LMC3...
  • Page 15: Mechanism Adjustment

    SECTION 2 MECHANISM ADJUSTMENT 2.1 BEFORE STARTING REPAIR AND ADJUSTMENT 2.1.1 Precautions (1) Unplug the power cable of the main unit before using Loading motor your soldering iron. (2) Take care not to cause any damage to the conductor wires when plugging and unplugging the connectors. (3) Do not randomly handle the parts without identifying where the trouble is.
  • Page 16 2. In case of mechanical failure (3) Take the spring of the pinch roller arm assembly off the If you cannot remove the cassette tape which is loaded be- hook of the press lever assembly, and detach it from the cause of any mechanical failure, manually remove it by tak- tape.
  • Page 17: Jigs And Tools Required For Adjustment

    2.1.4 Jigs and Tools Required for Adjustment Alignment tape (SP) Alignment tape (EP) Back tension cassette gauge A/C head positioning tool MHP-L PUJ48076-2 PTU94010 Roller driver Jig RCU Torque gauge PTU94002 PTU94023B PUJ48075-2 Table 2-1-1 Jigs and tools required for adjustment 2.1.5 Maintenance and Inspection 1.
  • Page 18 Loading arm gear (supply side) Capstan motor Capstan brake assembly Belt (loading motor) Belt (capstan) Loading arm gear (take-up side) Plate (supply side) Control bracket1 Worm gear Control cam Control plate Brake lever Tension arm bearing Cassette gear Link lever Direct gear Rotary encoder Take-up head...
  • Page 19 Note: This table shows the order in which parts are removed for replacement. To replace parts, remove them in the order of 1 to 18 as shown in the table. To install them, reverse the removal sequence. The circled numbers (symbols and numbers) preceding the individual part names represent the numbers in the "Lo- cation of major mechanical parts"...
  • Page 20: Replacement Of Major Parts

    2. Cleaning Operation Hours System Parts Name Regular cleaning of the transport system parts is desirable ~1000H ~2000H but practically impossible. So make it a rule to carry out clean- ¤R ing of the tape transport system whenever the machine is Upper drum assembly serviced.
  • Page 21: How To Set The Mechanism Assembling Mode

    This unit is provided with a mechanism assembly mode. It 2.2.3 Cassette Holder Assembly is therefore necessary to enter this mode for assembling and 1. How to remove disassembling procedures. (1) Remove the guide rail and roller cam assembly. (See This mode is usually not in use, manually set it when it is Fig.2-2-2.) required.
  • Page 22 (4) While swinging the lock levers (R) and (L) of the cassette holder assembly toward the front, slide the cassette holder assembly until its legs come to where the guide Cassette holder assembly rail and the roller cam assembly have been removed (so that the drive arm is upright).
  • Page 23 2. How to install (Phase matching) (1) Insert the section A of the drive arm into the section B of the main deck. (2) Insert the section 1 of the drive gear into the round hole, and the section 2 into the square hole on the drive arm. (See Fig.2-2-7.) (3) Hold the drive arm upright and fit the leg C on the right side of the cassette holder assembly into the groove.
  • Page 24: Pinch Roller Arm Assembly

    2.2.4 Pinch Roller Arm Assembly 2.2.6 Audio Control Head 1. How to remove 1. How to remove (1) Remove the spring from the hook of the press lever as- (1) Remove the two screws (A) and remove the audio con- sembly.
  • Page 25: Loading Motor

    2.2.7 Loading Motor 2. How to install (Centering the mounting position) When the capstan motor has once been removed and then 1. How to remove reinstalled out of the initial correct position in the rotational (1) Remove the belt wound around the worm gear. direction, the capstan motor current may be unstable dur- (2) Open the two lugs of the motor guide and remove the ing operation in high or low temperatures.
  • Page 26: Pole Base Assembly (Supply Or Take-Up Side)

    2.2.9 Pole Base Assembly (supply or take-up side) 2.2.10 Rotary Encoder 1. How to remove 1. How to remove (1) Remove the UV catcher 2 on the removal side by loos- (1) Remove the screw (A) and remove the rotary encoder ening the screw (A).
  • Page 27: Clutch Unit

    2.2.11 Clutch Unit 1. How to remove (1) Release the two lugs of the rotary encoder guide in the (1) Remove the belt wound around the capstan motor and arrow-indicated direction and remove the change lever the clutch unit. assembly. (2) Remove the slit washer and remove the clutch unit.
  • Page 28: Cassette Gear, Control Cam And Worm Gear

    2. How to install (Phase matching) 2.2.14 Cassette Gear, Control Cam and Worm Gear (1) Slide the control plate so that its mark E is aligned with 1. How to remove the mark M on the loading arm gear shaft. (See Fig.2-2- (1) Remove the control cam by lifting it.
  • Page 29: Loading Arm Gear (Supply Or Take-Up Side) And Loading Arm Gear Shaft

    2. How to install (Phase matching) 2.2.16 Loading Arm Gear (supply or take-up side) and (1) Adjust the position of the idler arm assembly pin as indi- Loading Arm Gear Shaft cated in Fig.2-2-30 (to the left of center of the R section). 1.
  • Page 30: Take-Up Lever, Take-Up Head And Control Plate Guide

    Take-up lever Idler arm assembly pin Loading arm gear shaft Lug(C) Projection A Screw(A) Projection B Take-up head Lug(A) Lug(B) Loading arm gear (take-up side) Control plate guide Fig. 2-2-34 Fig. 2-2-33 2.2.18 Capstan Brake Assembly 2. How to install (1) Align the notch of the loading arm gear (take-up side) to 1.
  • Page 31: Sub Brake Assembly (Take-Up Side)

    2.2.19 Sub Brake Assembly (take-up side) (5) When installing the main brake assembly (take-up side), slide the brake lever in the direction as indicated by the 1. How to remove arrow to prevent it from hitting the projection of the main (1) Remove the spring attached to the lid guide and sub brake assembly (take-up side).
  • Page 32: Idler Lever, Idler Arm Assembly

    2.2.22 Idler Lever, Idler Arm Assembly 2.2.24 Rotor Assembly 1. How to remove (1) Remove the stator assembly. (1) Remove the lug of the idler lever from the main deck (2) Remove the two screws (B) and remove the rotor as- and remove the hook fitted in the idler arm assembly hole sembly.
  • Page 33: Upper Drum Assembly

    2.2.25 Upper Drum Assembly (3) Install the cap to the upper drum assembly. (4) Position the collar assembly as indicated in Fig.2-2-46 1. How to remove while controlling its up- down movement. (1) Remove the stator assembly and rotor assembly. (2) Loosen the screw of the collar assembly using a 1.5 mm hexagonal wrench and remove the collar assembly.
  • Page 34: Compatibility Adjustment

    2.3 COMPATIBILITY ADJUSTMENT Notes: • Although compatibility adjustment is very important, it is not necessary to perform this as part of the nor- mal servicing work. It will be required when you have replaced the audio control head, drum assembly or any part of the tape transport system.
  • Page 35: Checking/Adjustment Of The Height And Tilt Of The Audio Control Head

    (1) Play back the alignment tape (A). (2) Apply the external trigger signal to D.FF (E), to observe the AUDIO OUT waveform and Control pulse waveform at the measuring points (D1) and (D2) in the ALT mode. (3) Press the channel buttons (+, –) simultaneously to enter the manual tracking mode.
  • Page 36: Checking/Adjustment Of The Standard Tracking Preset

    [Perform steps (6) to (9) adjustments only for 2 Heads (1) Play back the alignment tape (A). LP mode models.] (2) Apply the external trigger signal to D.FF (E), to observe the V.PB FM waveform at the measuring point (D). (6) Then play back the alignment tape (A2).
  • Page 37 Mechanism Timing Chart EJECT CASS- Mechanism mode CASS-INS FF/REW STOP SLOW/STILL PLAY Control plate mark HIGH C CH HIGH Rotary encoder B CH HIGH A CH Control cam angle 264. 318. 412. Rotary encoder 114. 150. 167. 178. 207. 218. 240.
  • Page 38: Electrical Adjustment

    SECTION 3 ELECTRICAL ADJUSTMENT 3.1.3 Color (colour) bar signal,Color (colour) bar pattern 3.1 PRECAUTION The following adjustment procedures are not only neces- s Color bar signal [NTSC] s Color bar pattern [NTSC] sary after replacement of consumable mechanical parts or White(100%) (75%) board assemblies, but are also provided as references to...
  • Page 39: Evr Adjustment

    3.1.5 EVR Adjustment (4) Adjust tracking by pressing the channel buttons (+, –) so that the V.PB FM waveform becomes maximum. Some of the electrical adjustments require the adjustment (5) Set the VCR to the Auto adjust mode by transmitting the performed by the EVR system.
  • Page 40: Video Circuit

    3.3 VIDEO CIRCUIT 3.3.1 D/A level Y level Signal (A1) • Ext. S-input / Ext. input 1.00 ± 0.05 Vp-p (A2) • Color bar signal [NTSC] Mode (B1) • S-VHS (B2) • EE Equipment • Oscilloscope H. rate Measuring point (D) •...
  • Page 41: Pb Y Level (S-Vhs/Vhs)

    (10) After adjustment, record the signal (A3) then playing it 3.3.5 Video EQ (Frequency response) back again. At this time, confirm that there is no invert- Signal (A1) • Ext. S-input ing phenomenon or noise appearing on the playback (A2) •...
  • Page 42: Audio Circuit

    3.4 AUDIO CIRCUIT DEMODULATOR CIRCUIT Notes: Note: • This adjustment should be done after the “REC color • Unless otherwise specified,set an audio multiplex TV (colour) level adjustment” for the video circuit has been signal generator as follows; completed. RF signal : 70 dBµ / 75 Ø , color bar 87.5% modulation. •...
  • Page 43: Stereo Filter

    3.5.3 Stereo filter 3.5.5 Separation - 2 Signal • RF signal (Audio: No signal) Signal • RF signal (Audio: L-ch 5 kHz 14% modulated) Mode • Tuner • EE Mode • Tuner Equipment • Oscilloscope • EE Measuring point • IC1501 pin 26 [Demod board] Equipment •...

This manual is also suitable for:

Hr-s4800u

Table of Contents