Panasonic RX-C300 Manuale utente

ORDER

NO.

GAD85032238C1

Service

Manual

Radio

Cassette

RX-C300

(Black)

Portable

Stereo

Component

System

@

SPECIFICATIONS

This

is

the

Service

Manual

for

the

following

areas.

[MI...For

U.S.A.

[Cl.

..

For

Canada.

General:

Power

Requirement:

(MJ...

AC;

110~115/115~127/200~220/

Max.

size

230~250

V,

50/60

Hz

System

[Cc]...

AC;

120

V,

60

Hz

2316”

(W)X15%46”

(H)X71%6”

(D)

Battery;

15

V

(Ten

“D”

Size

Flashlight

(585

x

382x202)

mm

Batteries)

(UM-1

or

equivalent)

Car

battery;

with

optional

car

adaptor

RP-9550

Tuner

Amplifier

9”

(W)x6%6”

(H)x71%6”

(D)

(228

x

157X201)

mm

Cassette

Deck

Power

Consumption:

60

W

(AC

only)

9”

(W)x6%6”

(H)X71%”

(D)

Power

Output:

80

W

...MPO

(228

157x190)

mm

Speaker:

Woofer;

67/2”

(16

cm),

PM

Dynamic

Speaker

(5Q)

7316”

(W)xX

12%"

(H)X7V2”

(D)

Squawker;

21%”

(6.5

cm)

PM

Dynamic

,

(182311190)

mm

Speaker

(5Q)

Weight:

;

10.8

kg

(23

Ib.

13

02.)

without

batteries

Tweeter;

1¥/2”x2”

(2.8

cmx4.7

cm)

Radio

Section:

Ceramic

Speaker

(1.4kQ)

Radio

Frequency

Input:

MIC;

sensitivity

0.8

mV/applicable

Range:

FM;

88~108

MHz

microphone

impedance

200~600Q,

@3.5

AM;

525~1610

kHz

PHONO;

sensitivity

5

mV/47

kQ

over

Intermediate

Frequency:

FM;

10.7

MHz

LINE

IN/CD;

sensitivity

200

mV/47

kQ

over

AM;

455

kHz

DCIN;

13.2V

Sensitivity:

FM;

2.5

uV/SO

mW

output

Output:

LINE

OUT;

sensitivity

420

mV/4.7

kQ

under

(—3

dB

Limit

sens.)

EXT

SP;

5~80

AM;

71

uV/m/50

mW

output

HEADPHONES;

32Q,

@3.5

Tape

Deck

Section:

EXT

ANTENNA

and

EARTH

Frequency

Response:

40~

15,000

Hz

(with

normal

tape)

Dimensions:

Not

included

handle,

projecting

parts

40~

16,000

Hz

(with

CrOz

tape)

Panasonic.

and

controls

40~

16,000

Hz

(with

Metal

tape)

System

Recording

System:

AC

bias,

AC

erase

23/16”

(W)

X12”

(H)X7%6”

(D)

Tape

Speed:

4.8

cm/s.

(1%

ips)

;

(585x305

x

185)

mm

Track

System:

4-track

2-channel

stereo

recording

and

Tuner

Amplifier

87/6”

(W)x57%”

(H)X7%6”

(D)

(215x

150X185)

mm

Cassette

Deck

87/6”

(W)X5%”

(H)x

7%”

(D)

playback

(215x

150x185)

mm

Speaker

7%”

(W)X12”

(H)X7Vi6”

(D)

“Dolby”

and

the

double-D

symbol

are

(181

x305x

180)

mm

00

DOLBY

SYSTEM

trademarks

of

Dolby

Laboratories

Weights

and

dimensions

shown

are

approximate.

(Les

poids

et

dimensions

mentionnés

sont

approximatifs.)

Design

and

specifications

are

subject

to

change

without

notice.

Matsushita

Engineering

and

Service

Company

50

Meadowland

Parkway,

Secaucus,

New

Jersey

07094

P.O.

Box

774

Matsushita

Electric

of

Canada

Limited

Panasonic

Hawaii

Inc.

91-238

Kauhi

St.

Ewa

Beach

Honolulu,

Hawaii

96808-0774

Licensing

Corporation.

Noise

reduction

system

manufac-

tured

under

license

from

Dolby

Labor-

atories

Licensing

Corporation.

Panasonic

Sales

Company,

Division

of

Matsushita

Electric

of

Puerto

Rico,

Inc.

Ave.

65

De

Infz.nteria,

KM

9.7

Victoria

Industrial

Park

Carolina,

Puerto

Rico

00630

5770

Ambler

Drive,

Mississauga,

Ontario,

L4W

2T3

a

Dx

Ox]

0)

CONTENTS

ITEM

PAGE

ITEM

PAGE

Safty

Precautions/Insulation

Resistance

Test

...............

2

SElectricaliPants:List’

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20

e@Location

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Controls

and

Components

................0-5-

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Schematic

Diagram

(Cassette

Deck)

Model

RX-C300........

22

eDisassembly

Instructions

.............

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4

@Circuit

Board

and

Wiring

Connection

Diagram

(Cassette

Deck)

e@Measurements

and

Adjustments

.................0000

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6

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RX=C300

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SCITCUIE

DESCHIPLIONS:

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Parts

Location

..............

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28

eSchematic

Diagram

(Tuner)

Model

RX-C300

..............

11

@Cabinet

Parts

LOCAtOM

s.sic3:5:é:scsce-s

aisosrare

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drarerarannaeeiara

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29

eSchematic

Diagram

(Amplifier)

Model

RX-C300

............

14

eCircuit

Board

and

Wiring

Connection

Diagram

(Tuner

Amplifier)

Model

RX-C300

.........

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17

easy

a

SAFETY

PRECAUTIONS

(For

u.s.a,)

Before

servicing,

unplug

the

power

cord

to

prevent

an

electric

shock.

When

replacing

parts,

use

only

manufacturer’s

recommended

components

for

safety.

Check

the

condition

of

the

power

cord.

Replace

if

wear

or

damage

is

evident.

After

servicing,

be

sure

to

restore

the

lead

dress,

insulation

barriers,

insulation

papers,

sheilds,

etc.

Before

returning

the

serviced

equipment

to

the

customer,

be

sure

to

make

the

following

insulation

resistance

test

to

prevent

the

customer

from

being

exposed

to

a

shock

hazard.

INSULATION

RESISTANCE

TEST

(For

u.s.a.)

1.

2.

3.

Unplug

the

power

cord

and

short

the

two

prongs

of

the

plug

with

a

jumper

wire.

Turn

on

the

power

switch.

Measure

the

resistance

value

with

ohmmeter

between

the

jumpered

AC

plug

and

each

exposed

metal

cabinet

part,

such

as

screwheads,

antenna,

control

shafts,

handle

brackets,

etc.

Equipment

with

antenna

terminals

should

read

between

3MQ

and

5.2MQ

to

all

exposed

parts’.

(Fig.

1)

Equipment

without

antenna

terminals

should

read

approximately

infinity

to

all

exposed

parts.

(Fig.

2)

*

Note:

Some

exposed

parts

may

be

isolated

from

the

chassis

by

design.

These

will

read

infinity.

.

If

the

measurement

is

outside

the

specified

limits,

there

is

a

possibility

of

a

shock

hazard.

The

equipment

should

be

repaired

and

rechecked

before

it

is

returned

to

the

customer.

Antenna

terminal

Exposed

metal

part

Ohmmeter

Fig.

1

Resistance

=

3M2—5.2MQ

Exposed

metal

part

Ohmmeter

Fig.

2

Resistance

=

Approx

LOCATION

OF

CONTROLS

AND

COMPONENTS

TUNER

AMPLIFIER

@

Function

Selector

(FUNCTION)

@

FM

Mode

Selector/Beat

Proof

Switch

(FM

MODE/B.P)

©

Band

Selector

(BAND)

@

FM

Stereo

Indicator

(FM

ST)

©

Tuning

Indicator

(TUNING)

©

Tuning

Control

(TUNING)

@

Volume

Control

(VOLUME)

©

Balance

Control!

(BALANCE)

©

Graphic

Equalizer

Controls

(GRAPHIC

EQUALIZER)

@

Headphones

Jack

(PHONES)

23.5,

320

When

using

the

headphones,

avoid

listening

to

sound

for

a

long

period

of

time

and

avoid

excessive

volume

levels,

which

may

injure

your

ears.

@

Spectrum

Analyzer

Switch

(SPECTRUM

ANALYZER)

@

Spectrum

Analyzer

(SPECTRUM

ANALYZER)

Blank

Skip

Function

Pressing

the

Blank

Skip

Switch

during

tape

playback

will

set

the

unit

to

the

TPS

mode

when

a

blank

interval

of

more

than

15

seconds

is

detected

on

the

tape,

and

playback

will

begin

from

the

start

of

the

eUseful

for

skipping

over

the

unrecorded

portion

at

the

end

of

the

tape

during

Auto-Reverse

Playback.

—————>

Tape

Running

Ln

DG

Ox630)0)

CASSETTE

DECK

®

Cassette

Compartment

@®

Tape

Counter

and

Reset

Button

(COUNTER)

®

Eject

Button

(4

EJECT)

@®

Reverse

Mode

Selector

(REVERSE

MODE)

@

“Dolby

Noise

Reduction

Switch

(DOLBY

NR)

®

Blank

Skip

Switch

(BLANK

SKIP)

®

Playback

Button

({

REV-PLAY-FWD

»

)

@

Stop

Button

(1JSTOP)

@

Fast

Forward/Rewind

Button

(«

FF/REW

»)

@

Mixing

Level

Control

(MIXING

LEVEL)

®

Record

Muting

Button

(Q

REC

MUTE)

@®

Record

Standby

Button

(@

REC

STANDBY)

®

Recording

Indicator

(REC)

®

Forward

Indicator

(FWD)

@

Tape

Selector

(TAPE

SELECTOR)

®

Timer

Standby

Selector

(TIMER

STANDBY)

®

Microphone

Jacks

(MIC)

23.5,

0.8

mV,

200~600Q

Connect

the

Mixing

Microphone

to

the

left

channel

(marked

[L)).

@

Power

Switch

(POWER)

@

Reverse

Indicator

(REV)

@

Power/Battery

Check

Indicator

(POWER/BATT)

REAR

PANELS

®

External

Antenna

Terminals

(FM

ANT)

@®

Line/CD

Input

Jacks

(LINE

IN/CD)

®

Phono

Input

Jacks

(PHONO)

©

Phono

Ground

Terminal

(_|

)

@

Telescopic

Antenna

@®

Speaker

Terminals

(SPEAKER

IMP

5-80)

Connect

to

the

speakers

with

included

speaker

cables.

@®

Battery

Compartment

@

DC

Input

Jack

[DC

IN

13.2

VV

(12-15V)

O-5-@

]

@

AC

Socket

(AC

IN.)

@

Voltage

Selector

(VOLTAGE

SELECTOR)

For

U.S.A.

only.

@®

Female

Connectors

Connect

with

included

cables.

@

Line

Output

Jacks

(LINE

OUT)

Note:

The

Blank

Skip

Function

may

not

work

correctly

with

some

pre-recorded

tape,

such

as

classical

music

where

there

are

many

low

sound

levels.

In

this

case

set

the

Blank

Skip

Switch

to

“OFF”.

SSS

ESS

ENS

less

than

15

sec

(no

skip)

aera

Pre-recorded

portion

Heese

Blank

portion

more

than

15

sec.

-—

Skip

(Simulated

Cue

eo

Simulated

TPS

fees

i

more

than

4

sec.

RX-C300

DISASSEMBLY

INSTRUCTIONS

Fig.

5

Fig.

6

the

eject

button,

the

spring

will

go

out.

RX-C300

Tuner

circuit

board

oe

o

AM

530

600

700

SCALE

0

2

y

2

STARTING

=

———

POINT

Display

circuit

board

(Q)

(R)

Fig.

11

Fig.

13

k

Cassette

Dec

Front

cabinet

Pull

out

the

tape

amplifier

circuit

board

until

it

is

possible

to

remove

the

switch

circuit

board

Power

transformer

Battery

circuit

board

Push

the

tooth

and

remove

the

circuit

board

in

the

direction

of

arrow.

Pull

out

the

gear

Cassette

holder

Push

the

cassette

holder

in

the

direction

of

arrow

@.

Remove

the

spring

in

the

direction

of

arrow

©.

Front

cabinet

«1,

2

*

1.

Turn

the

drum

gear

in

the

direction

of

arrow

@

as

shown

in

fig.

9.

*2.

Set

the

pointer

at

the

position

as

shown

in

fig.

13.

*3.

The

speaker

box

is

made

of

a

relatively

soft

material

(9-mm-thick

particle

board).

Be

careful

not

to

tighten

the

screws

excessively

when

attaching

anything

to

the

box

in

order

not

to

damage

the

threads.

elf

the

threads

are

damaged,

also

use

a

bonding

agent

to

attach

the

speaker

box

stopper

to

the

speaker

box

so

that

the

speaker

box

does

not

fall

when

attached

to

the

main

unit

(tuner

amplifier

block

or

cassette

deck

block).

=>

Fe

nD,

Oxs10)0)

MEASUREMENTS

AND

ADJUSTMENTS

&

ALIGNMENT

INSTRUCTION

READ

CAREFULLY

BEFORE

ATTEMPTING

ALIGNMENT.

1.

Set

volume

control

to

minimum.

2.

Set

graphic

equalizer

to

center.

3.

Set

band

switch

to

AM

or

FM.

4.

Set

balance

control

to

center.

&

MW

and

SW

ALIGNMENT

Fashion

loop

of

several

turns

of

wire

and

radiate

signal

into

loop

of

receiver.

455

kHz

30%

Mod.

at

400

Hz

AM

(5)

&

FM

ALIGNMENT

SIGNAL

GENERATOR

or

SWEEP

GENERATOR

CONNECTIONS

FREQUENCY

BAND

10.7

MHz

(SWP.)

High

side

thru.

0.001

UF

to

test

(1)

point

7

.

Negative

side

to

test

point

W

.

(2)

SIGNAL

GENERATOR

or

SWEEP

GENERATOR

CONNECTIONS

FREQUENCY

Tuning

capacitor

Tuning

capacitor

CT6

(AM

OSC

(*

1)Cement

antenna

bobbin

with

wax

after

completing

alignment.

5.

Set

mode

switch

to

stereo.

6.

Set

power

source

voltage

to

15

V

DC.

7.

Output

of

signal

generator

should

be

no

higher

than

necessary

to

obtain

an

output

reading.

INDICATOR

RADIO

DIAL

(ELECTRONICS

SETTING

VOLTMETER

REMARKS

‘ADJUSTMENT

“|

T2

(AM

IFT)

L7

(AMOSC

Coil)

or

SCOPE)

AM-IF

ALIGNMENT

Point

of

non-

interference.

(on/

about

600

kHz)

Output

meter

across

voice

coil

Adjust

for

maximum

output.

MW-RF

ALIGNMENT

Adjust

for

maximum

output.

Adjust

for

maximum

output.

Adjust

L4

by

moving

coil

bobbin

along

ferrite

core.

Adjust

for

maximum

output.

Repeat

steps

(2)~(5).

(*1)L4

(AM

ANT

Coil)

CT3

(AM

ANT

Trimmer)

INDICATOR

(ELECTRONICS

VOLTMETER

or

SCOPE)

FM-IF

ALIGNMENT

Connect

vert.

amp.

of

scope

to

test

point

Y

.

Negative

side

to

test

point

7

.

RADIO

DIAL

ADJUSTMENT

REMARKS

SETTING

Point

of

non-

interference.

(on/

about

90

MHz)

Adjust

for

maximum

amplitude.

(Refer

to

fig.

6).

T1

(FM

1st

IFT)

Adjust

for

maximum

amplitude.

(Refer

to

fig.

7).

T3

(FM

2nd

IFT)

(3)

Connect

to

test

point

109.2

MHz

W

through

FM

dummy

antenna.

Negative

(4)

side

to

test

point

Y

.

(5)

90

MHz

FM

(6)

po

106

MHz

(*

2)

Three

output

responses

will

be

present:

proper

tuning

is

the

center

frequency.

FM-RF

ALIGNMENT

Output

meter

Variable

:

L3

(FM

OSC

(

*

2)

Adjust

for

maxi-

capacitor

across

‘

fully

closed

voice

coil

ce)

EOD

Variable

CT2

(FM

OSC

"

capacitor

ss

anoss

er)

fully

open

mesma

|_|

:

(

*

2)

Adjust

for

maxi-

CT1

(FM

ANT

mum

output.

Trimmer)

Repeat

steps

(3)~(6).

3

YG.

Oz

10)

0am

2D,

O01

010)

&

SEPARATION

ALIGNMENT

FM

SIGNAL

GENERATOR

SOURCE

CONNECTION

EQUIPMENT

CONNECTION

ELECTRONIC

COUNTER

ADJUSTMENT

SPECIFICATION

REMARKS

98

MHz,

60

dB

(CW)

Connect

to

test

point

W

through

FM

dummy

antenna.

Negative

side

to

test

point

Y.

Adjust

VR1,

for

19

kHz

(+150

Hz)

reading

on

electronics

counter.

Adjustment

of

pilot

signal

@

AUDIO

ADJUSTMENT

MEASUREMENT

ITEM

INPUT

POINT

ADJUSTMENT

SPECIFICATION

POINT

REMARKS

QZZCAC

: ;

:

Maximum

Azimuth

screw

Playback

mode

(1)

a

20

ne}

EXT

SP

(Refer

to

Fig.

2.)

|

(FWD

and

REV

Playback)

WY...

(Reh)

Playback

mode

mij

genase

aia

dB)

VY.

(ich)

410+25

mV

Me

tee

Tape

switch

...

Normal

,

W...

(-)

Dolby

NR

...

OUT

Record

mode

(3)

Ese

nn

¥:

2

180"

43

mV

VR302

Beat

proof

switch—

II

:

dil

Tape

switch—

Metal

;

Use

normal

WY...

(Leh)

Normal

4.8

+0.2

mV

Record

mode

Bias

VR101

(Lch)

:

(4)

and

metal

WY...

(Reh)

Beat

proof

switch

II

current

tape.

W.(-)

Metal

8.341.5mV

|

VR201

(Roh)

Tape

switch—

Normal—

Metal

1.

Apply

a

—24

dB

1

KHz

signal

from

the

line

input

terminal.

2.

Measure

the

output

voltage

of

line

output

terminals.

3.

Then,

with

the

unit

in

the

record

mode

and,record

the

signal

Line

IN

VR102

(Lch)

4.

Playback

the

recorded

part,

(5)

f=1

kHz,

Output

voltage

VR202

(Reh)

and

measure

the

output

—24dB

...0+1

dB

voltage

of

line

output

terminals.

5.

Compare

the

output

voltage

measured

in

items

2

and

4,

and

adjust

so

there

is

no

difference

in

the

level.

(Adjust

to

obtain

0+1

dB.)

REMARKS

Use

oscilloscope.

Overall

gain

Line

OUT

@

SPECTRUM

ANALYZER

ADJUSTMENT

MEASUREMENT

ITEM

INPUT

POINT

ADJUSTMENT

1C204—Pin

@

to

@...(+)

CS2—Pin

@...(—)

SPECIFICATION

less

than

+0.05

V

need

adjustment

—___

Limit

voltage

adjustment

Do

not

supply

any

audio

signal.

need

adjustment~

Total

level

‘

snl

Set

graphic

fats

Line

In

Total

level

indicator

The

red

segments

are

not

:

indicator

=

:

VR602

es

equalizer

to

adjustment

ec

AN

[vee

|

Rarorneeas

center.

@

TAPE

SPEED

ADJUSTMENT

COUNTER

Connect

to

earphone

jack

ADJUSTMENT

1.

Play

back

test

tape

(QZZCWAT,

3

kHz).

2.

Adjust

VR

until

3000

Hz+90

Hz

is

read

on

the

counter.

CAUTION

(Refer

to

Fig.

9.)

Observe

the

following

precautions

when

connecting

a

measuring

device

other

than

the

accompanying

speaker

to

an

external

speaker

jack

or

a

P.C.

Board.

Note:

When

connecting

an

external

measuring

device

to

an

output

line,

connect

an

electrolytic

capacitor

between

them

to

cut

the

direct

current.

Also,

the

positive

(+)

and

negative

(—)

terminals

of

the

left

and

right

channels

must

be

connected

independently

with

respect

to

direct

current

and

alternating

current.

Be

particularly

careful

that

measuring

devices

connected

to

different

channels

and

placed

in

close

proximity

to

each

other

do

not

contact

each

other.

Hf

=

@

ALIGNMENT

POINT

@Please

refer

to

Circuit

Boards

and

Wiring

Connection

Diagram

which

is

located

test

point.

Total

level

indicator

R/P

Head

FWD

REV

Fig.

2

&)

Tape

speed

TAPE

PHONO

LINE.

FM

MODE

FM

AM

Ao

6P

Fig.

3

Fig.

4

é

teat

Overall

gain

verall

gain

[VR202]

VRIO2

Bias

current

iQ)

VRIOI

Bias

current

e

VR20l

Fig.

6

Playback

level

Playback

level

VRIOO

VR200

Erase

current

Total

level

Fig.

5

Output

terminals

of

set

35

V

2200

x2

35

V

2200

ux2

+--+

AM

IFT

455kHz

Fig.

7

Fig.

8

Oscilloscope

(Example

of

connection

of

external

measuring

devices)

Fig.

9

Vv

Be

sure

to

fold

at

the

(V)

mark

so

that

mark

is

on

the

outside.

=

3

35

V

2200

ux2

AM

ANT

SSOkHz

AMOSC

1650kHz

AM

ANT

Limit

voltage

VR6OO

5

DG

Ox

11)

0

teen

DG

Ox

10)

0)

CIRCUIT

DESCRIPTION

CP5-2(Rch)

CP4-2

Tape

Amp

O

IC

208

Power

IC

200

Q401—404,

e400

IC

209

its

BPF.

VR400—

404

;

4

Power

G.EQ

|

Ame

Circuit

|

Q600

Q6I7

Q50!—

504,

>

-

VR500

—

504

<|

G.EQ

Circuit

VR505

Total

Amp

_

VR405,505:

Volume,

VR6OI:

Balance

1C

205

e608

K

I2.5kHz

B.P.F.

1c

207

Sampling

Pulse

Generator

jouBIS

plsd

JaAlIQ

4019N

14

IC

206

IC204

|DUBIS

aAl4ig

juawbas

}OuUBIS

aAIUg

4aLaW

DC-AC

Converter

Q61l2

,613

T600

Fig.

1.

Block

Diagram

Display

Principle

of

the

Spectrum

Analyzer

The

output

signal

(tape

playback,

line,

or

radio

signal)

from

the

tape

amplifier

circuit

board

passes

through

the

power

amplifier

circuit

and

then

is

input

to

Q400

and

Q500

on

the

graphic

equalizer

circuit

board.

The

output

from

Q400

and

Q500

is

divided

into

two

signals.

One

is

input

to

the

graphic

equalizer

circuit

composed

of

Q401—Q405,

Q501—505,

VR400—409,

and

VR400—404,

and

after

its

100

Hz,

330

Hz,

1

kHz,

3.3

kHz,

and

12.5

kHz

frequency

components

have

been

attenuated

or

amplified

between

—10

dB

and

+10

dB

by

the

respective

graphic

equalizer

controls,

the

signal

is

fed

back

to

Q400

and

Q500

and

added

ito

the

original

sound.

The

other

signal

passes

through

the

balance

and

volume

controls

and,

in

addition

to

being

input

to

the

power

amplifier,

it

is

sent

through

R404

and

R504

to

the

Q600

and

Q617

amplifiers

as

a

left

and

right

mixed

signal.

The

output

of

these

amplifiers

is

input

to

the

|C200—-1C203

band

pass

filter

and

then

is

passed

through

a

smoothing

circuit

composed

of

a

diode

and

a

condenser

from

which

it

is

output

as

a

DC

signal.

The

selective

frequencies

of

the

band

pass

filter

are

determined

by

the

value

of

the

CR

attached

to

the

outside

of

each

IC.

IC

Selective

Frequencies

Output

No.

1C200-8

1C200-2

1C201-8

1C201-2

IC202-8

1C202-2

1C203-8

1C203-2

Further,

in

1C205

208

Hz

signals

each

with

shifted

phases

are

made

and

output

from

pins

9-16.

These

are

then

sent

to

the

|C207

grid

driver

and

Q601—608

sampling

gates.

The

signal

sent

to

C207

is

inverted

and

then

input

to

grids

1—8

of

the

F/L

meter.

The

signal

converted

to

a

DC

signal

by

IC200-IC

203

and

their

peripheral

circuits

is

input

to

sampling

gates

Q601—Q608,

and

when

a

low

signal

is

then

input

to

the

base

of

each

gate,

the

gate

closes

and

the

signal

is

output

to

4

of

IC204.

The

DC

signal

input

to

1C204

is

converted

to

a

seven-step

meter

drive

signal

and

input

to

1C206,

from

which

it

is

output

to

the

F/L

meter

as

a

segment

drive

signal.

In

addition

to

the

above

grid

drive

signal

and

segment

drive

signal,

a

322

Hz

AC

voltage

is

applied

to

the

F/L

meter

by

a

DC/AC

converter

circuit

composed

of

Q612,

Q613

and

T600

and

used

as

the

power

supply

for

the

filament.

4.8msec

IC

207-18

FL

-

32,33

--H--4---+--+---]---]---F--

Grid

8

1

:

|

ic207-17

1

'

FL-1,2

Grid

7

'

|

1

t

!

1

i

I

Ic207-16

|

'

Grid

6

| !

i

bresiini

cet

C207

152)

4

|

1 !

Grid

5

1

!

1

I

1

H

t

'

|

i

|

Ic207-

14

|

4

1

'

Grid

4

1

|

| I

1

|

!

eH

1 !

I

|

1

|

Ic207-13

|

\

\ \

Grid3

| |

i

'

1

H

1

|

Bes

\ !

\

ic2zo7-12

|

1

:

--

Grid

2

1

|

:

\

oe

7

1

:

\

,

\

|

I

H

|

Fig.

3.

‘‘F”

Signal

8G

7G

6G

5G

4G

3G 2G

IG

Ic207-11

Grid

|

t

WY

WM.

Fig.

2.

Timing

Chart

:

1@,olwolo!wio!

1—

NIGI

SII

OIA

Fig.

4.

FL

Tube

33)82|

31

|solecies|e7

|26|e5|2q[e3|29|21

|20]

19]

18|17/16|15]

14]

13|12|

1

[10]

9|8|7]6

[5

]4|

3]

2]

8

i

6

5

4

3 2

|

Foe

G

|NC|NC]

G

|NC|NC|NC}

G

|NC/NC]

G

|NC/NC}

G

|NC/B7|

G

B5|G

B3|B2|

G

F

Fig.

5.

FL

Tube

Assignment

ch

—~10—

IC2

BA4234L

AMOSC

AMIN

IC1

RVITA7358P

iIC4

RVIBA328MR

PLL

F

SEPARATION

EEPIELER

CONTROL

PLL

FILTER

L

OUT

R

ouT

(5)

LAMP

FILTER

(16)

vco

MONO

LAMP

OUT

Ae3

RVITA7358P

fo

Be8

BA4234L

CHECK

(2)

‘is

ceed

Ce7

RVIBA1332L

+Vec

De3

RVIBA328MR

mee

©

Be6

2SC1359B

D:8

2SA564R

Fe8

2SC1740R

E6

2SC1740R

E6

2SC1740R

Ce9

2SA564R

Be4

MA840B

Be4

MA165

Notes:

BeG

MA165

1.

$18,

S19:

Band

switch

in

‘‘FM”

position.

ie

ries

el

(S18-1,

S18-2...FM,

S19-1...AM)

Ess

RVDOMTze6ReB

2.

$22~S24:

Function

switch.

E-8

MA165

(S22-1~S22-4...

TAPE,

S23-1~S23-3...PHONO,

$24-1~S24-3...LINE/CD)

3.

S25-1,

S25-2:

FM

Mode/Beat

Proof

switch

in

“STEREO/I”

position

(1...

STEREO/I,

3...

MONO/II)

4.

VR1:

VCO

adjustment.

5.

DC

voltage

measurement

are

taken

with

electronics

voltmeter

from

negative

terminal

of

battery.

<

>...FM,(

)...AM,

No

mark...

Phono

===

)

Voltage

Line

eaaa=p

FM

Signal

Line

c=»

Tape/Phono/Radio/CD/LINE

IN

Varicap

Zener

Anode

GND

FMIFIN

BYPASS

AF

OUT

MUTE

15

DG

Ore]

0]

0

ead

a

GL

Ox10]0)

AGC

AM

Vec

AM

MIXOUT

AMIFIN

BYPASS

FM

QUAD

Vcc

AMDET

OUT

AMAF

IN

GND

FM

FRONT

END

FM

IF

DET

AM

OSC

IF

FM

MPX

PHONO

AMP.

FM

IF

AMP

MUTING

REGULATOR

BUFFER

AMP

BUFFER

AMP

SWITCHING

AFC

AGC

SWITCHING

TUNING

IND

FM

ST

IND

ZENER

SWITCHING

General

Anode

TELESC

ANTENNA

SCHEMATIC

DIAGRAM

(Tuner

OPIC

A

IC

gu»

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asyd

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&

4.

B

Cc

Stl

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}

Pleomax

Oe]

=

3

200mV

AC,

=

c

(47KQ..0VER)

1

ned

2

S2g-

S242

)

2

-

24-3

20:

sists

3

&

|

530

53

c

(ark.

over!

+

i

PHONO

EARTH

¢

E

Photo

Diode

NN

F

Cathode

fit

Cathode

Anode

Cathode

—12—

RX-C300

TELESCOPIC

ANTENNA

08v)

5

DG

O61010)

SCHEMATIC

DIAGRAM

(Tuner)

MODEL

RX-C300

S18-2

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IC

Rat

220K

C45

14V10

G4Vv)

dv)

sv)

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~

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BV)

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&8¥)

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(OV

42V)

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(S1W)

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BB)

BW)

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BBV)

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SQ)

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is

ea

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he

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Moot

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al

dy

C

x

C52

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471K

agv.

av

SV

38V—O8V

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nile

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C10

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©

OUT

=>

(|

OUT

(R)

(TAPE

HIGH

Photo

Diode

Roo

100

S

]

=

-

ms

Hg

or

tet

rode

Cathode

249i

Vv

—13—

Panasonic RX-C300 Manuale utente

Manuali Impianto stereo popolari di altre marche