Panasonic PV-4601 A, PV-4601 B, PV-4601-K, PV-4651, PV-4651-K Service Manual

ORDER NO. MKS9512M303

Video Cassette Recorder

PV-4601 A PV-4601 B

PV-4601-K

PV-4651

PV-4651-K

SPECIFICATIONS

ITEM SPECIFICATIONS 1 2 Power Source: 120 V AC ±10%, 60Hz ±0.5%

o Consumption: Approx. 18 watts (Power on), Approx. 6

watts (Power off) Approx. 23 watts (Power on), Approx. 7 watts (Power off)

o --

Video Head: 4 rotary heads helical scanning system o o

Input Level: VIDEO IN Jack (Phono type) 1.0 Vp-p 75

ΩΩΩΩ

unbalanced Output Level: VIDEO OUT Jack (Phono type) 1.0 Vp-p 75

ΩΩΩΩ

unbalanced Signal-to-Noise Ratio: SP: more than 43 dB LP/SLP: more than 41 dB Horizontal Resolution: Color/Monochrome: more than 230 lines

o o

Audio Head: Normal Mono: 1 stationary head

Hi-Fi Stereo: 2 rotary heads

o -o

Input Level: AUDIO IN Jack (Phono type) -10 dBV 50 k

ΩΩΩΩ

unbalanced Output Level: AUDIO OUT Jack (Phono type) -8 dBV 600

ΩΩΩΩ

unbalanced AUDIO OUT Jack (Phono type) -8 dBV 1 k

ΩΩΩΩ

unbalanced

o o

Frequency Response: Normal Mono: SP: 100 Hz ~ 8 kHz LP: 100 Hz ~ 6 kHz SLP: 100 Hz ~ 5 kHz Hi-Fi Stereo: SP/LP/SLP: 20 Hz ~ 20 kHz

o o o

o Signal-to-Noise Ratio: Normal Mono: SP: more than 42 dB LP/SLP: more than 40 dB Hi-Fi Stereo: SP/LP/SLP: more than 60 dB

o o

o Wow and Flutter: Normal Mono: SP: Less than 0.2%

WRMS LP: Less than 0.3% WRMS SLP: Less than 0.4% WRMS Hi-Fi Stereo: Less than 0.015% WRMS

o o o

RF Out

CH 3/CH 4 switchable 72 dB

µµµµ

(open voltage) 75

ΩΩΩΩ

unbalanced

o o

Tuner Broadcast Channels: VHF 2 ~ 13, UHF 14 ~ 69

CATV Channels: Midband A through I (14 ~ 22) Superband J through W (23 ~ 36) Hyperband AA ~ EEE (37 ~ 64) Lowband A-5 ~ A-1 (95 ~ 99) Special CATV channel 5A (01) Ultraband 65 ~ 94, 100 ~ 125

o o

Video Signal EIA Standard (525 lines, 60 fields) NTSC Color Signal o o

Tape Speed SP: 1-5/16 i.p.s (33.35 mm/sec), LP: 21/32 i.p.s (16.67

mm/sec), SLP: =7/16 i.p.s (11.12 mm/sec) Record/Playback Time: 8 Hrs with 160 min. type tape used in SLP mode FF/REW Time: Less than 5 min. (120 min. type tape)

o o

Tape Format Tape width 1/2° (12.7 mm) high density tape o o Operating

Condition

41=A1F (5=A1C) ~ 104=A1F (40=A1C) (Temperature) 10% ~ 75% (Humidity)

o o

Dimension 14-3/16" (360 mm) (W) X 3-1/2" (89 mm) (H) X 11-1/4" (285

=mm) (D)

o o

Weight Approx. 7.9 lbs. (3.6 kg)

Approx. 8.2 lbs. (3.7 kg)

o --

Use The Marks(A,B,...)shown in the chart bellow to distinguish the different moddels included in this Service Manual.

MODEL MARK PV-4601 A A PV-4601 B B PV-4601 -K C PV-4651 D PV-4651-K E NOT USED Z

IMPORTANT SAFETY NOTICE

There are special components used in this equipment which are important for safety. These parts are marked by /triangle =up triangle, open]in the Schematic Diagrams, Circuit Board Diagrams, Exploded Views and Replacement Parts List. It is essential that these critical parts should be replaced with manufacturer's specified parts to prevent shock, fire or other hazards. Do not modify the original design without permission of manufacturer.

1. SAFETY PRECAUTIONS

1.1. GENERAL GUIDELINES

1. When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or damaged by the short circuit.

2. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers shields are properly installed.

3. After servicing, make the following leakage current checks to prevent the customer from being exposed to shock hazards.

1.2. LEAKAGE CURRENT COLD CHECK

1. Unplug the AC cord and connect a jumper between the two prongs on the plug.

2. Measure the resistance value, with an ohmmeter, between the jumpered AC plug and each exposed metallic cabinet part on the equipment such as screwheads, connectors, control shafts, etc. When the exposed metallic part has a return path to the chassis, the reading should be between 1M ohm and 5.2M ohm. When the exposed metal does not have a return path to the chassis, the reading must be

∞∞∞∞

Figure 1

1.3. LEAKAGE CURRENT HOT CHECK (See Figure 1.)

1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.

2. Connect a 1.5K ohm, 10 watts resistor, in parallel with a 0.15 micro farad capacitor, between each exposed metallic part on the set and a good earth ground such as a water pipe, as shown in

Figure 1.

3. Use an AC voltmeter, with 1000 ohms/volt or more sensitivity, to measure the potential across the resistor.

4. Check each exposed metallic part, and measure the voltage at each point.

5. Reverse the AC plug in the AC outlet and repeat each of the above measurements.

6. The potential at any point should not exceed 0.75 volts RMS. A leakage current tester (Simpson Model 229 or equivalent) may be used to make the hot checks, leakage current must not exceed 1/2 milliamp. In case a measurement is outside of the limits specified, there is a possibility of a shock hazard, and the equipment should be repaired and rechecked before it is returned to the customer.

2. PREVENTION OF ELECTRO STATIC DISCHARGE

(ESD) TO ELECTROSTATICALLY SENSITIVE(ES)

DEVICES

Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor "chip" components. The following techniques should be used to help reduce the incidence of component damage caused by electro static discharge (ESD).

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any ESD on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging ESD wrist strap, which should be removed for potential shock reasons prior to applying power to the unit under test.

2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.

4. Use only an anti-static solder removal device. Some solder removal devices not classified as "antistatic (ESD protected)" can generate electrical charge sufficient to damage ES devices.

5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.

6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material).

7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed. CAUTION : Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD) sufficient to damage an ES device).

"NOTE to CATV system installer:

This reminder is provided to call the CATV system installer's attention to Article 820-22 of the NEC that provides guidelines for proper grounding and, in particular, specifies that the cable ground shall be connected to the grounding system of the building, as close to the point of cable entry as practical."

Model : D, E Equipped with dbx ® -TV Noise Reduction for true MTS reproduction. dbx ® -TV Noise Reduction is required for good stereo separation and audio fidelity.

3. SUMMARY

3.1. BASIC OPERATIONS

3.2. HELPFUL SERVICE NOTES AND CAUTIONS (Please read)

3.2.1. Simplified Fault Finding Data

Simplified Self-Diagnostic System facilitates finding the cause of the fault. A 4 digit fault code will be displayed in F.I.P. The Simplified Fault finding data is memorized for approximately 12 hours. This data is cleared after it is displayed and then the Power button is pressed back on.

1. With power turned off, press FF button on VCR for over 3 seconds as shown in

Fig.

1-1.

Fig. 1-1

2. Fault code (4 digit number) will be displayed in F.I.P. as shown in Fig. 1-2 and Fig.

1-3.

Fig. 1-2

Fig. 1-3

Explanation of Codes Code No. S-Tab SW Data

- S-Tab SW is off. 1

- S-Tab SW is on. 2 Take Up and Supply Photo Sensor Data

- No light detected at either sensor. 1

- Take Up Photo Sensor detected at beginning of tape.

- Supply Photo Sensor detected at end of tape.

- Light detected at both sensors. 4 Present Mechanism Position Code Mechanism Position is indicated. (Refer to

Fig. 1-4.)

1 2 3 4 5 6 7 8 9 A

Lock Code

- VCR is not in shut-off condition. 0

- Reel lock. 1

- Cylinder lock. 2

- Exceeds loading/unloading time. (Mechanism Lock)

- Exceeds Cassette loading/unloading time. (Cassette Lock)

Explanation of Codes Code No. Tape Loading (direction) 1 4 Tape Unloading (direction) 2 4

Fig. 1-4

3. While pressing down FF button on VCR with power turned off, press any operation button on either VCR, or remote to detect that a key has been pressed. 1st digit changes to "0" only when key is detected.

Fig. 1-5

Note:

When 1 to 4 listed in Lock code occurs, the VCR goes into VCR shut-off condition. VCR stops and all VCR function buttons except for power become non-operational.

3.2.2. Service Position

1. Service Position (1)

Service Position (1) is used for checking and replacing Mechanical and Electrical parts. To position the VCR Unit for servicing as shown in

Fig. 2-1, use the following

procedure.

1. In the order described in the Disassembly of Cabinet Parts Section, remove the Top Cover, Power Supply Ass'y and Front Panel Ass'y .

2. Remove Screw (S-4) and Screw (S-5) in

Fig. D4, Page 2-2.

3. Remove 2 Screws (S-6), 2 Screws (S-7), 2 Screws (S-8), Screw (S-9), Screw (S-10), Screw (S-11), 2 Screws (S-12), and the Chassis Plate in

Fig. D7, Page 2-3.

4. Remove the VCR Chassis Unit. Refer to Note Item 5 and "How to remove the VCR Chassis Unit from the frame," Page 1-11.

5. Remove 2 Screws (S-13) in

Fig. D8, Page 2-3.

6. Open the Mechanism Chassis and Cassette Up Ass'y.

7. Place the left side of the Cassette Up Ass'y on the front side of the Frame as shown in

Fig. 2-1.

8. Reinstall the Power Supply Ass'y as shown in

Fig. 2-1, refer to Note Item 4.

9. Press VCR/TV button and CH down button together on VCR for over 5 seconds in power off condition or Place a jumper between TP6001 and GND.

Fig. 2-1

Note:

1. When placing the unit into the Service Position (1), Beats may be seen in the picture. However, when the Red Screw between the Main C.B.A. and the Power Supply AssÕy is tightened, the Beats in the picture will be eliminated. So, place a short ground jumper wire between the Power Supply AssÕy and the Main C.B.A. while operating in the Service Position (1).

2. When servicing in Service Position (1), do not use a T160 tape. It may cause a Tape Jam.

3. If misloading of the cassette tape is encountered in this position, press the

Cassette Tape firmly into the Cassette Up Ass'y with your left thumb.

4. To install the Power Supply Ass'y to the Main C.B.A.: Connect connector P1001 and hook the tab of the Shield Case to the slot of the Main C.B.A. as shown in

Fig. 2-2.

Fig. 2-2

5. When lifting up the VCR Chassis Unit, do not pull up on the Top Plate of the Cassette Up Ass'y.

6. Model : D, E When raising or opening the mechanism, place something insulated between the Hi-Fi Audio/Video Head Amp Ass'y and Audio Jack.

Service Position (2)

Service position (2) is used to check the Mechanism and Electronic Circuits.

In this position, check the movement of mechanical parts on the Mechanism Chassis and replace parts as needed. In this position, checking is limited on the electronic circuit of the Main C.B.A. from the component side. To position the VCR Unit for servicing as shown in

Fig. 2-3, use the following

procedure.

1. In the order described in the Disassembly of Cabinet Parts Section, remove the Top Cover and Front Panel Ass'y.

2. Remove Screw (S-5) in

Fig. D4, Page 2-2.

3. Remove 2 Screws (S-6), 2 Screws (S-7), 2 Screws (S-8), Screw (S-9), Screw (S-10), Screw (S-11) and the Chassis Plate in

Fig. D7, Page 2-3.

4. Remove 2 Screws (S-13) in

Fig. D8, Page 2-3.

5. Raise the Mechanism Chassis and secure it using the Chassis Plate which was used to secure the Mechanism Chassis on the frame as shown in

Fig. 2-3.

6. Press VCR/TV button and CH down button together on VCR for over 5 seconds in power off condition or Place a jumper between TP6001 and GND.

Fig. 2-3

3.2.3. How to reset all VCR Memory functions

To reset (clear) the select language, channel auto set and set clock functions to their initial power on condition (power on, no cassette inserted), hold down the PLAY and REWIND buttons together on VCR for more than 5 seconds. Power will shut off .

3.2.4. Service Mode

In order to inhibit detection of the Supply and Takeup Photo Transistors, Reel Sensor, and Cylinder Lock, press VCR/TV button and CH down button together on VCR for over 5 seconds in power off condition. The power comes on and the unit goes into service mode. Mechanism movement can be confirmed without a cassette in this mode. To release from this mode, press POWER button off or disconnect AC Plug. (Alternative method) Ground the TP6001.

Fig. 3

3.2.5. Test Point Information

Test Point purpose operation TP6001 T o confirm mechanism

movement without a cassette, the detection of the Supply / Takeup Photo Transistors, Reel Sensor, and Cylinder Lock will be inhibited.

Ground the TP6001

TP6003 T o defeat the Auto

Tracking Function. (Maintain the Neutral Position.)

Place a jumper between TP6003 and TP6009(+5V).

TP6011 A check Terminal for

judgment of the IC6001 microprocessor. The microprocessor is OK if there is Scan pulse output.

TP6301 A check Terminal for

judgment of the IC6301 microprocessor. The microprocessor is OK if there is pulse output.

3.2.6. Easy check of Power Supply Ass'y, Hi-Fi Audio C.B.A., UHF/VHF

Tuner/TV Demodulator Unit

Power Supply Ass'y, Hi-Fi Audio C.B.A., UHF/VHF Tuner/TV Demodulator Unit can be checked easily through holes in the bottom of the frame after removing the Bottom Panel. You can check connector pins of following units and C.B.A.s.

P1051 (Pins of Power Supply Ass'y)

Pins of UHF/VHF Tuner/TV Demodulator Unit.

Model : D, E

P4201,P4202,P4203 (Pins of Hi-Fi Audio C.B.A.)

Fig. 4

3.2.7. VCR Lock Feature

This feature prohibits all operations except for timer recording, and tape eject. This is useful to prevent misoperation and protect your VCR.

To set the VCR Lock Feature:

Press STOP/EJECT button on VCR for 7 seconds during Stop, or Power OFF mode.

Fig. 5-1

To cancel the VCR Lock Feature:

Press STOP/EJECT button on VCR for 7 seconds again during Stop, or Power OFF mode.

Fig. 5-2

VCR Lock mode is cancelled automatically after 24 hours when the clock is set.

3.2.8. Set Tracking to the Neutral Position

Pressing eject and reinserting a Tape will initiate the Auto Tracking function from the Neutral position.

3.2.9. Easy Signal Check Points

Points with marks "V1..., AV1..., CT1... etc." on Main C.B.A. can be used for checking Video and Audio Signal.

V1 to V11 : to check Video Signal

AV1 to AV4 : to check Audio Signal

CT1 to CT7 : to check Control Signal

Also, power lines are marked with voltage indications (5V, 12V, 14V, 37V, -30V) on Main C.B.A. for easy checking. Schematic, C.B.A. and Block Diagrams also show these check points.

3.2.10. Function of important Test Points

Function of important Test Points TP3001 Video signal to Jack TP3002 PB/REC video envelope signal TP3009 Video signal from Jack TP4001 Audio signal from Jack TP4002 Audio signal to Jack TP6001 Service Test Point (inhibit sensors) TP6003 defeat Auto tracking function

(connect to +5V(TP6009)) TP6009 +5V *TP6010 AIP CTL signal *TP6011 IC6001 judgment TP6204 Cylinder PG/FG TP6205 Head SW TP6207 PB control pulse TP6301 IC6301 judgment

3.2.11. Method for Manual Loading / Unloading of VCR

Turn the Loading Pulley of the Motor Block Ass'y (shown in Fig. 6) counterclockwise (for loading) or clockwise (for unloading) as viewed from the Front Side.

Note:

DO NOT apply any voltage to the Terminals of the Loading Motor Unit on the Motor Block Ass'y.

Fig. 6

3.2.12. How to Remove a jammed Tape

A. Electrical Method

1. In the order described in the Disassembly of Cabinet Parts Section, remove the Top Cover and Front Panel Ass'y.

2. Cut the wire to open Jumper(J6004) on the System Control Section of the Main C.B.A. from the component side. (Refer to

Fig. 7-1.)

Note:

It is unnecessary to cut both wires (J6004 and J6005).

Fig. 7-1

3. Connect a DC Power Supply to the wire as shown in Fig. 7-2, then apply +6.0+-0.1VDC to J6004 in order to start the unloading operation sequence.

4. When the tape Loading Arms are returned to the fully unloaded position, disconnect the DC Power Supply Unit to stop the unloading operation.

Note:

Be careful not to let the DC power supply Unit GND contact chassis GND. This may damage the Loading Motor Drive IC (IC 6003). Be sure to connect DC +to side (a) of J6004. If DC + is applied to side (b) of J6004, the Loading Motor Drive IC (IC6003) may be damaged.

Fig. 7-2

5. To rewind the tape into the cassette, turn the Capstan Pulley counterclockwise as shown in

Fig. 7-3.

Fig. 7-3

6. Then eject the Tape using the DC Power Supply again.

7. After completion of the procedure, resolder the jumper wire (J6004) that was opened.

B. Manual Method

1. In the order described in the Disassembly of Cabinet Parts Section, remove the

Top Cover and Front Panel Ass'y.

2. Remove a Cut Washer (C-1) on the Pressure Roller Arm Unit as in

Fig. J3, Page

2-16.

3. Remove the Spring of the Pressure Roller Arm Unit as in

Fig. J3.

4. Turn the Pressure Roller Arm counterclockwise and lift it up to release from the Pressure Roller bracket and shaft.

5. Remove the tape from the tape path and posts.

6. Rewind the tape into the cassette by turning the Capstan Pulley counterclockwise as in

Fig. 7-3.

7. Remove the Cassette Up Ass'y by removing 2 Screws (S-7), 2 Screws (S-8), 2 Screws (S-14) and 2 Screws (S-15) as in

Fig. D7 and Fig. D9, Page 2-3.

8. Remove the cassette from the Cassette Up Ass'y.

9. Adjust the Mechanical Position into the Eject position by rotating the Loading Pulley.

10. Remove the Pressure Roller Bracket from shaft and reinstall the Pressure Roller Arm and spring to the bracket as in

Fig. J3.

11. Reinstall the Pressure Roller Arm Unit and Cut Washer in original position as in

Fig. J3.

12. Reinstall the Cassette Up Ass'y into the Mechanism Chassis.

3.3. OTHER SERVICE NOTES AND CAUTIONS

3.3.1. OTHER SERVICE NOTES AND CAUTIONS

Align the Sensor LED with the hole in the Mechanism Chassis by gently pushing the Sensor LED backward with your hand. Refer to

Fig. 8.

Fig. 8

3.3.2. How to remove the VCR Chassis Unit from the frame:

1. In the order described in the Disassembly of Cabinet Parts Section, remove the Top Cover, Power Supply Ass'y and Front Panel Ass'y.

2. Remove Screw (S-4) and Screw (S-5) in

Fig. D4, Page 2-2.

3. Remove 2 Screws (S-6), 2 Screws (S-7), 2 Screws (S-8), Screw (S-9), Screw (S-10), Screw (S-11), 2 Screws (S-12), and the Chassis Plate in

Fig. D7, Page 2-3.

4. While gently lifting the Side Plate L (C) of Cassette Up Ass'y, bent locking tab (A) and (B) then outward until clear.

5. Lift the Side Plate R (D) until even with the Side Plate L. Then lift entire VCR Chassis Unit out from the frame.

Fig. 9

3.3.3. Handling of the Main C.B.A. when Servicing

DO NOT pull the Main C.B.A. in the direction indicated by the arrow. DO NOT pull upward while holding the UHF/VHF Tuner/TV Demodulator Unit because you may crack the Main C.B.A.

Fig. 10

3.3.4. Removal/Installation of Mechanism Chassis to the Main C.B.A.

Preparation

1. In the order described in the Disassembly of Cabinet Parts Section, remove the Top Cover and Front Panel Ass'y .

2. Remove Screw (S-5) in

Fig. D4, Page 2-2.

3. Remove 2 Screws (S-6), 2 Screws (S-7), 2 Screws (S-8), Screw (S-9), Screw (S-10), Screw (S-11) and the Chassis Plate in

Fig. D7, Page 2-3.

4. Remove 2 Screws (S-13) in

Fig. D8, Page 2-3.

a. Removal

Remove the Mechanism Chassis as follows.

1. Lift up the Side Plate -R while holding the Main C.B.A. to disconnect the right rear mechanism connector.

2. Lift up the Side Plate -L while holding the Main C.B.A. to disconnect the left rear mechanism connector.

Fig. 11-1-1

Fig. 11-1-2

b. Installation

Connect the Mechanism Chassis to the Main C.B.A., as shown below. Be sure to press the rear portion of the mechanism chassis to insert connectors securely.

Fig. 11-2

3.3.5. How to remove the Cassette Up Ass'y

1. In the order described in the Disassembly of Cabinet Parts Section, remove the Top Cover and Front Panel Ass'y.

2. Remove 2 Screws (S-7) and 2 Screws (S-8) in

Fig. D7, Page 2-3.

3. Remove 2 Screws (S-14), 2 Screws (S-15), in

Fig. D9, Page 2-3.

3.3.6. When installing the Cassette Up Ass'y

When installing the Cassette Up Ass'y onto the Mechanism Chassis, make sure that the Cassette Up Ass'y and the mechanism are in the Eject position. See "HOW TO INSTALL CASSETTE UP ASS'Y ONTO MECHANISM CHASSIS," Page 2-23.

3.3.7. Connection of the Flat Cable to Trap Connector

Plug No. Location of Trap

Connectors

Type

P2505-P1541Unit A/C Head A P3504-FE Head Unit FE Head Unit B

To identify Pin 1 of the Flat Cable, a different Color Identification Line is used. To locate Pin 1 on the Trap Connector, find the pin 1 indicator on the C.B.A.

Fig. 12-1

Fig. 12-2

(Removal and Installation of the Flat Cable)

Type A

(Removal) Pull out the Flat Cable. Minimize stress by holding it securely to avoid damage of the individual wires. (See

Fig. 12-3.)

(Installation) Adjust the position of the Flat Cable so that the Identification Line on the Flat Cable aligns with Pin 1 of the Trap Connector and align the individual wire with its individual Trap Connector Hole. Then insert the Flat Cable wire into the Trap Connector.

+ 175 hidden pages

Panasonic PV-4601 A, PV-4601 B, PV-4601-K, PV-4651, PV-4651-K Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual