JVC KVV-8 Schematic

SECTION 4

24

C331
11/10

22201816

WF25

C329

0.1/50

C330

0.1/50

R344
47K

R343
18K

R345
10K

R346
15K

Measurement point

Waveform number

CHARTS AND DIAGRAMS

NOTES OF SCHEMATIC DIAGRAM

Safety precautions
The Components identified by the symbol are

critical for safety. For continued safety, replace safety
critical components only with manufacturer's recom­mended parts.

1. Units of components on the schematic diagram

Unless otherwise specified.

1) All resistance values are in ohm, 1/6 W, 1/8 W (refer to
parts list).
Chip resistors are 1/16 W.

K or k: k (1000 ), M: M (1000k )

2) All capacitance values are in µF, (P: PF).

3) All inductance values are in µH, (m: mH).

4) All diodes are 1SS133, MA165 or 1N4148M (refer to parts
list).

2. Indications of control voltage

AUX : Active at high

AUX or AUX(L) : Active at low

3. Interpreting Connector indications

1

2

Removable connector

3

1

2

Wire soldered directly on board

3

4) Indication on schematic diagram
Voltage Indications for REC and PB mode on the sche­matic diagram are as shown below.

REC mode

12 3

2.5

(5.0)

PB mode

1.8

PB and REC modes
(Voltage of PB and REC modes
are the same)

Note: If the voltages are not indicated on the schematic

diagram, refer to the voltage charts.

5. Waveform measurement

1) Video circuits
REC : Colour bar signal in SP mode, normal VHS mode
PB : Alignment tape, colour bar SP mode, normal VHS

mode

2) Audio circuits
REC : 1KHz, –8 dBs sine wave signal in SP mode, normal

VHS mode

PB : REC then playback it

3) Movie Camera circuits
Measured using a correctly illuminated gray scale or colour
bar test chatrs in the E-E mode

4) Indication on schematic diagram
Waveform indications on the schematic diagram are as
shown below.

1

Non-removable Board connector

2

3

1

2

4

Board to Board

3

Connected pattern on board
The arrows indicate signal path

4. Voltage measurement

1) Video circuits
REC : Colour bar signal in SP mode, normal VHS mode
PB : Alignment tape, colour bar SP mode, normal VHS

mode

— : Unmeasurable or unnecessary to measure

2) Audio circuits
REC : 1KHz, –8 dBs sine wave signal in SP mode, Nor-

mal VHS mode

PB : REC then playback it

3) Movie Camera circuits
Measured using a correctly illuminated gray scale or colour
bar test charts in the E-E mode

5) Waveform indications

Waveform number

WF25

REC/PB 1.2 Vp-p

50 mV/2 msec/DIV

Oscilloscope Volts and Time/Division, Probe 10 : 1

Mode : REC or PB modes

Waveform name or
measurement point

ALC OUT

Level : 1.2 Vp-p

4-1

6. Signal path Symbols

The arrows indicate the signal path as follows.

Playback signal path

Playback and recording signal path

Recording signal path
(including E-E signal path)

Capstan servo path

CIRCUIT BOARD NOTES

1. Foil and Component sides

1) Foil side (B side) :
Parts on the foil side seen from foil face (pattern face)
are indicated.

2) Component side (A side) :
Parts on the component side seen from component face
(parts face) indicated.

Drum servo path

(Example)

R-Y

Playback R-Y signal path

Y

Recording Y signal path

7. Indication of the parts for adjustments

The parts for the adjustments are surrounded with the circle as
shown below.

8. Indication of the parts not mounted on the circuit board

“OPEN” is indicated by the parts not mounted on the circuit
board.

R216

OPEN

2. Parts location guides

Parts location are indicated by guide scale on the circuit board.

REF No. LOCATION

Category: IC

Horizontal “A” zone

Vertical “6” zone

(A : Component side)

(D : Discrete component)

B : Foil side

C : Chip component

IC

IC101 B C 6 A

Note:

For general information in service manual, please refer
to the Service Manual of GENERAL INFORMATION Edi­tion 4 No. 82054D (January 1994).

4-2

4.1 BOARD INTERCONNECTIONS

5

)
A

(

(

ENABLE MOD OUT

Page 4-13

)

4

(

VIDEO/AUDIO Page 4-5

(

SYSCON Page 4-7

(

SW.REG Page 4-9

(

TERMINAL Page 4-11

)
)
)

)

3

CAP CTL V

2

LP/EP LP/EP

1

p20175001a rev0

ABCD EFGH

4-3 4-4

4.2 MAIN(VIDEO/AUDIO)SCHEMATIC DIAGRAM

The Parts Number,value and rated voltage etc. in the Schematic Diagram are for references only.

Note :

When replacing the parts,refer to the Parts List.

TO TERMINAL

MAIN(VIDEO/AUDIO

)

5

TO SW.REG

4

TO U.DRUM

HIFI MODEL HIFI MODEL

3

TO A/C HEAD
CN1

P/R

TO SYSCON

0

0

0

2

TO SYSCON

TO SW.REG

TO SYSCON

1

: Used
: Not used

JCP8020-MSD-2

4-5 4-6

p10294001a rev1.1

HGFEDCBA

4.3

MAIN(SYSCON)SCHEMATIC DIAGRAM

The Parts Number,value and rated voltage etc. in the Schematic Diagram are for references only.

Note :

When replacing the parts,refer to the Parts List.

TO SW.REG

0

5

TO CAP MDA

MONITOR 12V

TO DRUM MOTOR

SHORT

TO TERMINAL

OPEN

4

TO FRONT
CN7001

TO LOADING MOTOR

3

TO ROTARY ENCORDER

2.2

0

0

2

0

0

0

TO DEW SENSOR

0

TO VIDEO/AUDIO

1

: Used
: Not used

p10295001a rev1.1

ABCD EFGH

4-7 4-8