Kenwood Trc-70 User manual

TAC

70

KENWOOD

SERVICE

MANUAL

©

1989-11

PRINTED

IN

JAPAN

B51-8038-00

(O)

588

Knob

(POWER

SW)

Metallic

cabinet

Knob

Front

glass

Panel

ass'y

(DRESSING

PANEL)

(K29-4540-14)

(K29-4519-04)

{A01-1087-02)

(K29-4540-14)

(B10-1129-14)

|

(A20-7061-04)

Knob

(K29-4540-14)

x

4

S68

AAG

OTE

EPHONE

Microphone

Phone

jack

Label

Knob

(MAIN

DIAL)

Foot

Knob

(T91-0388-05)

(E11-0440-05)

(B42-3379-04)

(K29-4538-03)

(J02-0323-05)

x

4

(K29-4539-04)

x

2

CONTENTS

MAINTENANCE

AND

ADJUSTMENT

............cccccee

2

CONTROL

UNIT

(X53-3280-21)

.......ccccceensereenees

85

INSTALLATION

INSTRUCTIONS.

...........cscsceseners

5

TX-RX

UNIT

(X57-3470-21)

oc

eccscceccceenssenseresens

93

CIRCUIT

DESCRIPTION

..........cessessscscesteseneserseeserses

6

FINAL

UNIT

(X45-3370-21)

..........0csseeceereseereees

101

DESCRIPTION

OF

COMPONENTS

..........ccccseeess

27

SCHEMATIC

DIAGRAM

...........ssscsssseecerseeseeeeensees

105

PARTS

LIST

0.00...

ccseececeseeeeeeeseeseeseesnesecerseuanseentesees

33

MAT-100

(AUTOMATIC

ANTENNA

TUNER)

EXPLODED

VIEW.............:cecccsscsseussessectencecssseeeseeenes

63

Circuit

Description

........cccccccsseneceeereeeseeneneees

108

PACKING

........:.cscsesceceerceseeseserensecsereresucuarsseseesseeses

65

Block

Diagram

..........scssssscsnsssne

cecceneesenereenes

122

ADJUSTMENT

........csssscsessecsseseecercscerscesscenseevsuensass

66

Description

of

Components

.........-:cccecesseceee

123

LEVEL

DIAGRAM

...........::.scssecseessseeescencerstsseeseresees

76

Parts

List

...........-cessscsssorssessesssecessse

cnseneceserensenss

124

BLOCK

DIAGRAM

..........:ssccossscsnsssssneesessresseeeeses

77

Exploded

View

.......:..:cssscssssssesesesesssceenseeeeeees

129

TERMINAL

FUNCTION

............:ccssssssssssestssssseseeses

81

PC

Board

View

CIRCUIT

DIAGRAMS

/

PC

BOARD

VIEWS

LED

UNIT

(W02-0844-08)

...........:0ccreccceeeeees

130

LCD

ASS'Y

(B38-0324-05)

.........:cssessesseesseeerees

83

ANT

MODULE

UNIT

(W02-0883-08)

...........

131

VCO

(X58-3720-10)

.......sccsscstsssesnsenseessceeersneeses

83

Schematic

Diagram

..........ccsesseseeccccceeesneseeees

133

SIDE

TONE

(X59-1060-00)

.........c.csccsssneseesees

84

Installation

INStructiONS

..........cceeeeeeeeeneeneneees

136

DC-DC

(X59-1100-O0)

........scscssscccssesssseseeeesees

84

Manual

Tuning

.............---.:cecsseecenneneeeeeeresereees

140

FAN

&

TEMP

PROTECTION

(X59-3370-00)

.....

84

Specifications

..........ccccccssecseseseen

cnnesssecesseeeees

141

VCO

(X59-3440-00)

.......:ccssescsssesessseeeenenenecses

84

SPECIFICATIONS.

.......sccecsssssessereerersees

.

BACK

COVER

TRC-70

MAINTENANCE

AND

ADJUSTMENT

Service

Your

SSB

radiotelephone

has

been

factory

aligned

and

tested

to

specification

before

shipment.

Under

normal

circumstances

the

SSB

radiotelephone

will

operate

in

accordance

with

these

instructions.

All

adjustable

trimmers

and

coils

in

your

SSB

radiotelephone

has

been

adjusted

at

the

factory

and

should

only

be

readjusted

by

a

qualified

technician

with

proper

test

equipment.

Attempting

service

or

alignment

without

factory

authorization

can

void

the

SSB

radiotelephone’s

warranty.

When

operated

properly,

the

SSB

radiotelephone

will

provide

many

years

of

service

without

requiring

realignment.

The

information

in_

this

section

gives

some

general

service

procedures

which

can

be

accomplished

without

sophisticated

test

equipment.

Should

it

ever

become

necessary

to

return

the

equipment

to

your

dealer

or

service

center

for

repair,

pack

it

in

its

original

box

and

packing,

and

include

a

full

description

of

the

problems

involved.

Also

include

your

telephone

number.

You

need

not

return

accessory

items

unless

directly

the

service

problem.

Service

note

:

If

you

desire

to

correspond

on

a

technical

or

operational

problem,

please

make

your

note

short,

complete,

and

to

the

point,

and

PLEASE

make

it

readable.

Please

list:

Model

and

Serial

Number

The

problem

you

are

having.

Please

give’

sufficient

detail

to

diagnose.

Information

such

as

other

equipment

in

the

station,

meter

readings

and

anything

else

you

feel

might

be

useful

in

attempting

diagnosis

.

Caution

:

Do

not

pack

the

equipment

in

crushed

newspapers

for

shipment.

Extensive

damage

may

result

during

shipment.

Notes

:

1.

Record

the

Date

of

Purchase,

Serial

Number

and

Dealer

from

whom

purchased.

2.For

your

own

information,

retain

a

written

record

of

any

maintenance

performed

on

the

unit.

3.

When

claiming

warranty

service,

a

photocopy

of

the

bill

of

sale,

or

other

proof

of

purchase

showing

the

date

of

sale

must

accompany

the

radio.

TRC-70

MAINTENANCE

AND

ADJUSTMENT

Top

cover

g

Adjustment

1-1.

Cover

removal

Caution

Before

removing

the

cover,

turn

the

DC

power

supply’s

power

switch

OFF

and

disconnect

the

power

cable.

Do

not

pinch

wiring

when

opening

or

closing

cases.

Remove

the

top

cover

(8

screws),

and

the

bottom

cover

(4

screws)

from

radiotelephone.

1-2.

Sub

chassis

removal

Remove

the

4

screws

as

shown

in

the

diagram.

Open

in

a

counterclockwise

direction.

1-3.

Beep

tone

level

Turn

VR7

to

the

desired

BEEP

tone

level.

VR6

TONE

(ALARM)

1-4.

Tone

level

VR7

_1.

Press

the

TONE

key.

2.

Turn

VR6

to

the

desired

TONE

level.

TRC-70

MAINTENANCE

AND

ADJUSTMENT

1-5.

Microphone

connector

Front

view

MIC

@

GND

(MIC)

ss@

SPS

oO

DOWN

@

®

8M

GND

©

@

uP

@

MIC

impedance

approx.6000

@ss

Stand-by

switch

@DOWN

Frequency

or

Memory

channel

number

decrease

@upP

Frequency

or

Memory

channel

number

increase

@8M

8V(

Max.100mA)

@®SPS

Receive

audio

output

@GND(MIC)

Mic

ground

(GND

Ground

1-6.

13.6

VDC

Power

input

connector

\—@

DC

13.6

V

\___©

eno

1-7.

Antenna

coupler

connector

NC

@

AC2@

TS

©

@NC

Not

used

@TT

Control

signal

input/output

@GND

Ground

@aAC2

Antenna

current

input

@Ts

Control

signal

input/output

@FSB

Power.output

for

antenna

coupler

TRC-70

INSTALLATION

INSTRUCTIONS

Microphone

hanger

Tapping

screw

-

Microphone

hanger

Connection

This

radiotelephone

requires

a

maximum

of

30

A

at

13.6VDC

+

15%

when

transmitting

at

full

power.

Do

not

exceed

the

length

of

the

supplied

power

cable.

=—_—_

To

Antenna

“To

Antenna

tuner

(MAF-100)

.

Supplied

DC

cable

To

vessel's

battery

Wing

bolt

We

©

ss

To

antenng

Ground.

ye

@

©

iC)

Ei)

<n

terminal)

oy

|

©

Supplied

External

Speaker

plug

To

Externa!

speaker

1

Without

antenna

coupler

The

type

of

antenna

that

is

used

will

greatly

affect

the

performance

of

the

equipment.

Use

a

properly

‘adjusted

antenna,

of

good

quality,

to

enable

your

equipment

to

perform

at

its

best.

The

antenna

input

impedance

is

50

ohms.

Use

50

ohm

coaxial

‘cable

such

as

RG-8U

or

8D-2V

for

this

connection.

If

the

antenna

is

far

from

the

transceiver

the

use

of

low

loss

coaxial

cable,

such

as

RG-8U

is

recommended.

Match

the

impedance

of

the

coaxial

cable

and

that

of

the

antenna

so

that

the

SWR

is

less

than

1.5.

The

protection

circuit

in

the

transceiver

will

activate

if

the

SWR

is

particularly

poor

(greater

than

3

).

High

SWR

values

wili

cause

the

transmitter

output

to

drop.

Antenna

tuner

(MAT-

100)

With

antenna

coupler

A

wire

antenna

must

be

in

the

range

from

2

to

24

MHz

and

having

a

total

length

of

12 to

23

meters.

When

the

radiotelephone

is

operated

only

on

low

frequencies,

a

longer

antenna

is

preferable.

The

antenna

should

be

erected

as

high

as

possible.

The

insulator

should

be

able

to

withstand

high

transmitter

power

levels

without

leakage.

Typical

installation

and

connection

Connect

the

Antenna

connector

of

the

radiotelephone

to

the

RF

IN

jack

with

the

coaxial

cable,

such

as

RG-8U

are

recommended.

Connect

the

6P

connector

of

the

supplied

control

cable

to

the

radiotelephone.

Please

refer

to

the

MAT-100

Instruction

Manual

to

connect

with

the

cable

to

the

MAT-100.

TRC-70

CIRCUIT

DESCRIPTION

Frequency

Configuration

The

second

IF

signal

(10.695

MHz)

passes

through

a

crystal

filter,

and

is

then

applied

to

IC2

:

KCD03

where

the

signal

is

demodulated.

The

demodulated

audio

output

is

amplified

by

the

AF

preamplifier

and

power

amplifier

to

drive

the

speaker.

The

TRC-70

operates

as

a

double

conversion

sys-

tem

for

both

transmission

and

reception.

(See

Figure

1.)

*

Receiver

system

The

receive

signal

from

the

ANT

terminal

passes

through

the

final

unit

and

the

TX-RX

unit

LPF

and

is

applied

directly

to

mixers

Q9

and

Q10

(2SK125-5).

Here

the

signal

is

mixed

with

the

first

local

oscillator

frequency

(71.395~101.295

MHz)

from

the

PLL

in

or-

der

to

generate

the

first

IF

signal

of

71.295

MHz.

The

receive

frequency

may

be

fine

tuned

with

the

clarifier

by

varying

the

first

local

oscillator

frequency.

The

71.295

MHz

first

IF

signal

passes

through

a

monolithic

filter

(MCF)

and

is

mixed

with

the

second

local

oscillator

frequency

(60.6

MHz)

by

MIX

FETs

013

and

O14

(2SK520(K44))

to

generate

a

10.695

MHz

second

IF

signal.

The

second

local

oscillator

signal

is

generated

by

the

TX-RX

unit

Q90

and

Q91

(2SC2714(Y))

and

is

then

doubled

by

Q56

(2SC2714(Y)).

*

Transmitter

system

The

audio

signal

from

the

microphone

is

amplified

by

mic

amplifiers

O37

and

038

:

2SC3324(G),

and

is

then

combined

with

the

carrier

oscillator

in

the

bal-

anced

modulator,

(IC6

:

4PC1037A)

to

generate

the

TX

first

IF

(10.695

MHz).

In

the

H3E

mode,

a

carrier

signal

is

added

to

the

TX

first

IF

(10.695

MHz).

The

TX

first

IF

is

then

mixed

win

the

second

local

oscillator

frequency

(60.6

MHz)

by

|C7

:

SN16913P

in

the

same

manner

as

the

receiver

sys-

tem,

to

produce

a

71.295

MHz

signal.

This

signal

is

then

mixed

with

the

PLL

first

local

oscillator

frequency

in

order

to

generate

a

transmit

signal.

10.695MHz

SSB.CW.XF2

SP

Q29:2$C332.4

(GR)

IC2:KCOO03

Q13.14:2SK520(K44)

=

71.295MHz

Q9.10:2SK125-5

LPF

IC5:pPC1242H

OFT

2nd

MIXER

MCF

ist

MIXER

AF

10.695MHz

AMP

H3E_XF

BPF

ANT

0.\~3OMHz

XF3

TT

~~

7

ist

Local

freq.

CAR

71.395~101.295

MHz

USB

|

10.6965

MHz

|

USB:

+1.5

KHz

LSB

:10.6935MHz

PLL

LSB:

—1

5

KHz

RX:

CW:4+0.7KHz

CW-RxX

:

10.69

65MHz

osec2sceTiacy)

|

SYSTEM

|

CW-TX:

10.6957MHz

Q90.9I:

27iay)

H3E-RX:

O

KHz

H3E~-TX:

10.6965MHz

Zz

9

(x2)

|_|

|

HSE-TX:

445.5

KHz

=

a

2nd

local

|

"

a

G0.

6MHz

L_.

—_

—_J

10.695MHz

SSB.CW

H3E:ON

XF

(Shored

by

receiver

ystem)

—

71.295

MHz

MCF

(Shored

by

receiver

10.695MHz

H3E

+

y

=

FINAL.

MIC

XF

(Shared

by

:

+

NIT

pL

P.F

}—

AMP

receiver

system)

Thess

U

MIC

Q37.38

TX

BM

MIXER

Qi

Q4.5:

28028791(0,Y)

[28C3324(G)

!c6

=

IC7

:

SN16913P

Q51.52

:

2SC197I

1

PCIO37HA

:3SKI7T9(L)

022

3

CSI33

Fig.

1

Frequency

configuration

TRC-70

CIRCUIT

DESCRIPTION

The

reference

frequency

for

loops

A,

B,

and

C

is

10.1

MHz.

This

frequency

is

generated

by

dividing

the

30.3

MHz

reference

oscillation

frequency

by

3.

There-

PLL

(Phase

Locked

Loop)

The

TRC-70

PLL

is

divided

into

a

HET

loop

and

a

CAR

loop.

The

HET

loop

consists

of

loop

A

and

loop

B,

fore,

the

frequency

accuracy

of

the

HET

and

CAR

is

determined

by

the

30.3

MHz

oscillation

circuit.

and

the

CAR

loop

consists

of

loop

C.

Figures

2

and

3

show

a

block

diagram

of

the

HET

and

CAR

loops.

The

following

paragraphs

describe

loops

A,

B,

and

C.

doo

13H

Tid

jo

wesBelp

yoo1g

Z

“614

ZHWL'OL

wszzLaxo

|

WSZ7ZLOX9

|

l

o1s/t

£91

|

991

o0zo1/L

|

oosee

OLSE~120Z=W

GZ

E=W

|

’

zHx0z

|

~

ORAL

{

|

a-v

at

Od

N/L

}_|tAalpiczosz

|

N/L

Od

|

{

1

110

I

n-2

L-_J/_

—

—_

—__l

aw

||

LOE

Ty)

;

(A)PLZzosz

(p)stecosz

D)sceeosz

010

Lt

91

‘S10

4'9'SD

dwv

}

ddT

Nad

wary

PF;

a

ee

eee

-

OL-OZLE-BGX

12

00-

OFF

65x

i

f

t

3

ze

av

{zg>)

(Z9>)

zSy)

(ZS)

|

SODA

AN80SNSZ

AN8OSSZ

AN80S™SZ

doo

fis)

¥adooad

VIO~ET9

ODA

saa

soon

sn

|

_

;

.

4

ZHWS'6E

ZHINGEZ

LOL

ZHINGEZ

‘6

ZHWS6Z'S8

ZHWSEZ

BL

|

Sle

acorol

vot

~S6C'E6

~962'S8

~S6Z'BL

~S6E'LL

—

[_

J

RY

Ro

T6sbrSI

(A)

LLZOSz

TTT

‘a

ea

—_

£1

81D

vy

doo7

|

dda

poor

daw

(A)PLETOST

|

60

|

ZHWZ9'0L~9'rS

|

ZHWS'PS~ZZ'0b

—~

—

-|-

—

ZHINTS'OL

(ayy

jeD0}

381)

aINV

ZL

OY

dd

}

ZHAGEE

ZHIGEZ

LOL

~GSLE

~SBELL

—<«

(Alp

£Z9Sz

(A)

PL£ZOSz

NPLSOLNS

7H

d€L69LNS

—__

¥

i—

43H

FS

80

eof

G91

are

801

4d

dv

xIW

JW

XIN

TRC-70

CIRCUIT

DESCRIPTION

Loop

B

generates

a

37.5~39.5

MHz

signal

via

IC6

Frequency

(CXD1225M)

with

a

1

kHz

comparison

frequency.

The

_|

Function

O.1~7MHz

|

7~14MHz

|

14~22MHz

|

22~3OMH2

37.5~39.5

MHz

signal

is

generated

by

VCO6

(X59-

Microprocessor

|

V1

0

1

0

1

3440-00),

then

divided

by

100

in

C7

:

M54459L

to

gen-

control

signal

|

V2

0 0

1 1

erate

a

10

Hz

steps.

Fine-frequency

adjustment

by

means

of

the

clarifier

is

added

to

loop

B

under

micro-

processor

control.

The

375~395

kHz

output

signal

that

was

divided

by

100

by

IC7

is

mixed

with

the

30.3

MHz

BPF

BPFI

|

BPFI

|

BPF2

signal

by

IC8

:

SN16913P

in

order

to

generate

a

wo

as

30.675~30.695

MHz

signal.

This

frequency

passes

Table

1

Switching

of

Loop

A

VCO

and

BPF

through

MCF

(XF1;

30.685

MHz)

and

enters

IC5

vcoO

vco1

vCO2

VCO3

VvCO4

BPF2

(SN76514N).

Loop

A

generates

a

71.395~

101.295

MHz

signal

via

IC3

(CXD1225M)

with

a

comparison

frequency

of

20

J3E

USB.

CWR.

H3E=10.6965MHz

kHz.

This

signal

becomes

the

HET

oscillator

signal.

manana

ae

So

coese

The

loop

A

VCO

(X58-3720-10)

consists

of

four

sepa-

rate

VCO

circuits

which

are

selected

by

IC4

(TC4028)

AMP

{

FILTER

according

to

the

control

data

from

the

microprocessor.

UNLOCK

—sf

22?

cri

(See

Table

1.)

Part

of

the

loop

A

VCO

output

passes

2sc2714

{Y)

through

the

buffer

amplifier

of

Q9

:

28C2714(Y)

and

is

LPF

mix

4

applied

to

|C5.

The

signal

is

then

mixed

with

the

signal

x

1c11

from

loop

B

in

IC5

:

SN76514N

(40.72~70.62

MHz).

~~

SN16913P

The

resulting

40.72~70.62

MHz

signal

passes

through

v0}

10.1MHz

BPF1

and

BPF2.

VCO1

and

VCO2

pass

the

signal

through

BPF1,

and

VCO3

and

VCO4

pass

it

through

Wet

a50L

BPF2.

The

signal

passing

through

the

BPF

is

amplified

by

Q10

and

Q11

:

28C2714(Y)

and

is

then

applied

to

—22*

ot

a

PLL

IC3

(CXD1225™).

73

ws

Loop

C

generates

a

59.3~59.7

MHz

via

IC9

X59-3440-00

FMU1

(CXD1225M)

with

a

2

kHz

comparison.

This

VCO

out-

put

is

divided

by

100

by

IC10

:

M54459L,

and

is

mixed

LPF

i

with

10.1

MHz

by

IC11

:

SN16913P

to

generate

a

022,

23,

24

10.693~10.697

MHz

signal.

The

10.693~10.697

MHz

28C3325(G)

signal

passes

through

ceramic

filter

CF1

to

become

—_—

|—

——

—f—

the

CAR

signal.

The

CAR

signal

changes

with

the

[

L

mode.

It

is

amplified

by

Q27

and

is

then

sent

to

the

|

uN

Lt

pc

—»

C-U

TX-RX

unit.

|

N=29650~29850

{

1

|

1/5100

|

Ic9

:

CXD1225M

Fig.

3

Block

diagram

of

PLL

CAR

loop

TRC-70

CIRCUIT

DESCRIPTION

*

CAR

stop

circuit

in

AM

receive

mode

In

the

CW

and

SSB

modes,

the

8

V

DC

power

for

the

last

mixer

IC

(IC11

:

SN16913P)

of

the

CAR

loop

is

supplied

through

Q26

:

2SC2712(Y).

In

the

H3E

re-

ceive

mode,

8

V

is

applied

to

3

of

the

TX-RX

unit

shift

register

C10

(TC9174F)

according

to

the

data

supplied

from

the

microprocessor.

The

8

V

is

supplied

to

the

control

unit

via

the

CAR

coaxial

cable.

This

sets

028

:

DTC114EK

on,

changes

Q26

from

on

to

off,

disables

1C11,

and

stops

CAR.

¢

Unlock

circuit

Normally

8

V

(8C)

is

fed

to

the

HET

and

CAR

transis-

tors

O8

and

Q27

via

Q21.

(Q21

is

on.)

When

any

of

the

PLL

loops

(loop

A,

B,

and

C)

should

unlock,

8

of

the

corresponding

PLL

IC

(IC3,

IC6,

IC9

:

CXD1225M)

will

go

H

(5V).

This

causes

Q19

to

switch

on,

and

Q20

and

Q21

to

switch

off.

This

action

causes

the

voltage

applied

to

Q8

and

Q27

to

be

removed.

Meanwhile

Q29

switches

on,

and

LED

D10

turns

on

to

indicate

the

unlocked

state.

(cll

ouT

vcc

10.1IMHz

—-—_

LV

8S

a

7

SIG

kd

593~597

KHz

CFI

Vv

R92

Q27

CONTROL

UNIT

(PLL)

””

‘

(X53-3280-21)

1

|

R36

|

HET|

|

a8

|

i

|

r----

_

[o-oo

TX-RX

UNIT

(X57-3470-21)

RX:AM

MODE

8V

SHIFT

REGISTER

(170)

Fig.

4

CAR

stop

circuit

in

AM

receive

mode

and

PLL

unlock

circuit

TRC-70

CIRCUIT

DESCRIPTION

Control

Unit

¢

Control

unit

configuration

The

main

LSI

chips

in-the

control

unit

include

CPU

:

IC302,

ROM

:

1C310,

EEPROM

:

1C311,

and

extended

YO

IC

:

IC300.

The

CPU

reads

the

program

from

the

ROM,

reads/

writes

memory

channel

data

to

EEPROM,

and

inputs

and

outputs

signals

from

the

CPU

ports

or

extended

I/

O

IC

ports.

The

address

signal

(8

low-order

bits)

required

for

the

CPU

to

access

the

ROM,

EEPROM,

and

extended

1/0

iC

is

multiplexed

with

other

data

and

output

to

the

bus

line.

The

address

is

maintained

for

the

necessary

period

of

time

by

latching

1C303.

The

chip

select

(CS)

signal,

which

selects

a

the

desired

device

(ROM,

EEPROM,

etc.},

is

supplied

to

each

device

by

decoding

the

address

signal

by

C304

:

10

*

Bus

operation

The

ROM

(IC310),

EEPROM

(1C311),

and

extended

I/O

IC

(IC300)

are

connected

to

the

CPU

(IC302)

via

the

bus

line.

When

the

CPU

accesses

these

ICs

(iC310,

1C311,

and

1C300),

the

address

signals

(A13

to

A15)

output

from

the

CPU

are

decoded

by

1C304,

and

the

IC

is

specified

by

the

CS

signal.

1C310

(ROM)

uses

the

CPU

address

signal

A15

as

a

CS

signal.

Table

2

is

a

truth

table

for

IC304.

This

bus

is

a

multiplexed

bus

onto

which

an

address

code

and

data

are

output

alternately.

Therefore,

when

the

CPU

accesses

one

of

the

ICs,

the

necessary

ad-

dress

signal

is

latched

by

IC303.

This

latch

uses

the

positive

pulse

applied

to

the

ALE

pin,

after

the

CPU

outputs

an

address.

TC74HC138AF.

INPUT

OUTPUT

AlB|cC1¥o!¥1

1

Y2!

3]

Ya

|

Ys

|

Ye

|

Y7

oj;/o;o;otl1}7}1/111

71 41

o;/oj1);1/o0;1]/14)1)15111

ofi};olr}1}o0%r1f}4]144

41

olfi}airir}+riorprtr1)

14d

ass}

10304

7/o0/}o};1}1]71]1)/o0

47141

41

(decoder)

1

0

1 |

| 1

1

0

4 1

TC74HCI3Z8AF

7/1704]

47477

$7

$1)

041

1/1)

a7r)1]a]r74faqgia]o

ABA5

1c

302

TAble

2

Truth

table

for

IC304

:

TC74HC138AF

(CPU)

A0-7

IC303

(Latch)

sPD7BCIOAG-36

TC74HCS73AF

N—p

CS

00~7

Ke

IC3IO

A0-I3

(ROM)

27CI28-20

cs

<<

|s{

is)

IC3Il

2

ST

Taoctol|

(EEPROM)

w

m

g

MSM28C16

A-20RS

[cs

kK

Ic300

AO-2

(Extended

{/0)

CXxDIO95Q

Fig.

5

Control

unit

block

diagram

Kenwood TRC-70 User manual

Popular Cordless Telephone manuals by other brands