YAESU FT-4VE, FT-4VR, FT-4XE, FT-4XR Service manual

Technical Supplement

VHF/UHF DUAL BAND FM TRANSCEIVER

FT-4XR/FT-4XE

VHF FM Transceiver

FT-4VR/FT-4VE

Introduction

This manual provides the technical information necessary for ser-
vicing the FT-4XR/FT-4XE and FT-4VR/FT-4VE Transceiver.
Servicing this equipment requires expertise in handing surface-
mount chip components. Attempts by non-qualified persons
to service this equipment may result in permanent damage not
covered by the warranty, and may be illegal in some countries.
While we believe the information in this manual to be correct,
YAESU assumes no liability for damage that may occur as a
result of typographical or other errors that may be present. Your
cooperation in pointing out any inconsistencies in the technical
information would be appreciated.

EH069M90A

©2018 YAESU MUSEN CO., LTD.

Contents

Specications
Exploded View & Miscellaneous Parts
Block Diagram
Board Unit (Schematics & Layouts)

MAIN Unit

Caution

Risk of explosion if battery is replaced by an incorrect
type. Dispose of used batteries according to the instruc-
tions.

Important Note

This transceiver was assembled using Pb (lead) free

solder, based on the RoHS specication.

Only lead-free solder (Alloy Composition: Sn-3.0Ag-

0.5Cu) should be used for repairs performed on this
apparatus. The solder stated above utilizes the alloy
composition required for compliance with the lead-free
specication, and any solder with the above alloy com-
position may be used.

Specications

General

Frequency Range: FT-4XR/FT-4XE RX: 136 MHz - 174 MHz
400 MHz - 480 MHz
65 MHz - 108 MHz (FM Broadcast)
TX: 136 MHz - 174 MHz (Asian version)
144 MHz - 146 MHz (European version)
144 MHz - 148 MHz (USA version)
400 MHz - 480 MHz (Asian version)
430 MHz - 440 MHz (European version)
430 MHz - 450 MHz (USA version)
FT-4VR/FT-4VE RX: 136 MHz - 174 MHz
65 MHz - 108 MHz (FM Broadcast)
TX: 136 MHz - 174 MHz (Asian version)
144 MHz - 146 MHz (European version)
144 MHz - 148 MHz (USA version)
Channel Steps: 5/10/12.5/15/20/25/50/100
Mode of Emission: F2D, F3E, F2A
Frequency Stability: ±2.5 ppm (–4 °F to +140 °F [–20 °C to +60 °C])
Antenna Impedance: 50 ohms
Supply Voltage: Nominal. 7.4 V DC, Negative Ground SBR-28LI
Current Consumption (Approx.): 190 mA (Receive, 200 mW Audio Output)
95 mA (Standby, Saver OFF)
23 mA (Standby, Saver ON)
5 mA (Auto Power OFF)

1.5 A (5 W TX, 144 MHz) 7.4 V DC

1.7 A (5 W TX, 430 MHz) 7.4 V DC (FT-4XR/FT-4XE)
Operating Temperature: –4 °F to +140 °F (–20 °C to +60 °C)
Case Size (W x H x D): 2.0” x 3.5” x 1.2” (52 mm x 90 mm x 30 mm) (w/o knob and antenna)
Weight (Approx.): 8.82 oz (250 g) (with SBR-28LI and antenna)

kHz

Transmier

RF Power Output: 5 W (High) / 2.5 W (Middle) / 0.5 W (Low) (@ 7.4 V with SBR-28LI)
Modulation Type: Variable Reactance
Maximum Deviation: ±5 kHz
Spurious Emission: At least 60 dB below (@ TX Power High, Middle)
At least 50 dB below (@ TX Power Low) (USA/Asian version)
At least 55 dB below (@ TX Power Low) (European version)
Microphone Impedance (Approx.): 2 kohm

Receiver

Circuit Type: Direct-conversion
Sensitivity: 0.2 µV for 12 dB SINAD (140 - 150 MHz, NFM)

0.2 µV for 12 dB SINAD (420 - 470 MHz, NFM) (FT-4XR/FT-4XE)
Selectivity (–6 dB / –60 dB): FM, NFM ±25 kHz / 12.5 kHz

AF Output: 800 mW (16 Ω for THD 10 % 7.4 V DC) internal speaker
800 mW (16 Ω for THD 10 % 7.4 V DC) external speaker

Specifications are subject to change without notice, and are guaranteed within the 144 MHz amateur bands
only. Frequency ranges will vary according to transceiver version; check with your dealer.

Symbol Placed On The Equipment

Direct current

Specications - 1

FT-4XR/XE/VR/VE Technical Supplement

Exploded View

Serial Number

Please provide the serial number of the transceiver when ordering a
FT-4X/FT-4V MAIN BOARD ASEMBLY.
The serial number is located in the battery compartment of the
transceiver.

FT-4XR

SP/MIC CAP AH066
S8003350

VOL NUT AH066
S8003368

VOL KNOB AH066
S8003364

ANTENNA NUT AH066
S8003366

JACK COVER AH069
S8003428

O-RING-2 AH066
S8003358

O-RING-1 AH066
S8003356

②

①

②

②

①

②

②

②

②

FRONT PANEL ASSY

FT-4X (S8003416)
FT-4V (S8003418)

Speaker with wire
PTT/MON/Function rubber
Window with double face
Top LED light guide
Top button (orange)
Sponge for windows
Product name label

KEY PAD

FT-4X (S8003422)
FT-4V (S8003424)

LCD ASSY AH069
S8102444

LCD module
LCD holder

Light guide (including reector seat)

Interconnector

MAIN BOARD ASSY

FT-4X A2 version (S8102452)
FT-4X B2 version (S8102454)
FT-4X B3 version (S8102446)
FT-4V A2 version (S8102456)
FT-4V B2 version (S8102458)
FT-4V B3 version (S8102448)

About MAIN BOARD ASSY

The MAIN BOARD ASSY has been carefully assembled and aligned
at the factory. If a component part fails, the MAIN BOARD ASSY is
replaced as a complete unit.
Attempting replacement or repair of components on the MAIN
BOARD ASSY is not recommended.

REF YAESU P/N Description Qty.

①

Countersunk screw 2

SCREW KIT AH069

②
③

S8003432

Round head screw 7
Special screw 2

BELT CLIP SCREW

④

Non-designated parts are available only as part of a designated assembly.

S8003376

Belt clip screw 2

TERMINAL HOLDER AH069
S8003426

CHASSIS ASSY AH069
S8003430

Aluminum die-cast chassis
Rear plate
LATCH KIT AH066

Exploded View - 1

④

④

③

③

Antnna jack SMA
VOL
O-RING-1 AH066
O-RING-2 AH066
Mic cap

LATCH KIT AH066
S8003360

Countersunk screw 3pcs
Coil spling
Latch nail
Hold plate

FT-4XR/XE/VR/VE Technical Supplement

ANT

T

E

J

RX: 136-17 4&400~480 MHz

TX: 136- 174&400~480MHz

Block Diagram

FT-4XR / FT-4XE

LPF ANT SW

D808

BA592

Q802

FIN AL AMP

BAT T

U205

M4890

ANT SW

PB4/PA

5T

PB15

D809,D 810
BA892 X2

SW

SW

UTX

UR X

D802,D 803

BA892 X2

5TV

APC

U503

NJM2 904

Q504

RT1N
141U

LPF

.

ANT SW

D805

BA592

ANT SW

D806, D807

BA892 X2

U1

FM MOD ULE

RD A5802

Y1

201

XT S P

LS200

SP

J200

EXT MI C

32.768KHz

UTX

+3.3V

136~174MHz

78~108MHz

PB8 PB9

+5V

D200,D 201

DA 221,1SS372

Q204

DT C114EE

RQA0 009

AUDI O AMP

RQ A0009

400~480MHz

5TU

TONE

PA7

Q805

FIN AL AMP

Q800,Q804

Q803

2SC3356

FM A UDIO

MIC S W

U206

DTC114EE

RF AMP

5RU

RF AMP

5TV

AF

BAT T

Q801

2SK3078

DR IVE A MP

+5V

SW

Q502
DT A

144EE

SW

Q505
DT C

144EE

W200A

VOLU ME

MI C MOD

SG M4517

5TU

Q806

HE4226

5TU

RF AMP

5RV

SW

RF O UT

Q807

HE4226

RF I N

5TV

RF I N

SW

D812,D 813

BA892

5RU

5RV

AF SW

U201

SG M4517

+3.3V PA11

S521

3M3

TXCO

3M3

OSC 13.0MH z

U200

RD A1846S

RF MODU LE

(LNA, MIX, IF, RS SI,

SQ, AFC, CTCSS/D CS,

FM MOD EM, VCO,

LOOP F ILTER , VOX)

PA

PA7

VOX DET

SQ

S500~S509

S513~S520

KEY MAT RIX

DC SW

Q203

5T

DT A

123JE

5TV

5TU

AUDIO

TONE

DC SW

U202

SG M4157

X200

13.000MHz

PB10, PB11,PB12

DS 500
LCD

+5V

+3.3V

PA12

PA15

COM0~3

SEG 0~34

BLU E(B-RX)

FQC

3.3V REG.

PC13

SCL

J501

LCD D RIVE

+3.3V

D508

RED (TX)

PB13

SDA

GREEN(A-R X)

PC14

GD32 F101CBT6

MICR OPROCES SOR

PTT

PC15

U500

D503

LCD B ACK LIG HT

S511

Q506

2SC

1623

F/W

PA13

PD0

S512

MONI

PB0

SW

S510

EMERG ENCY

PA14

SD A

SCL

KEY B ACK LI GHT

PD1

UR X

PB4

PB7

PA7

PB8

PA8

PB9

PB5

PA11

PB6

PA15

D504~ D507

+3.3V

PA14

GND

PA13

UTX

EEPRO M

U504

AT24C128RM

+3.3V

J500

IDE-INT ERFACE

MK200
MI C

Q206

DTA

123JE

PD1

PTT DET

+3.3V

+3.3V PB14

+5V

5RV 5RU

Block Diagram - 2

PB7

PB6

SW SW

Q202

DT A

114EE

PB5

DC SW

Q205

DT C

114EE

Q201

DT A

114EE

PA8

3M3

+3.3V

U203

ME6206-33M

3.3V REG.

U501

ME6206-33M

5V R EG.

U502

ME6118A50

BAT T1

W200B

POWER SW

BAT T

D205
PROT ECTOR

BAT

7.4V

FT-4XR/XE/VR/VE Technical Supplement

T

J201
EXT SP

LS200

SP

J200

EXT MIC

LPF

ANT SW

BA592

ANT SW

D806, D 807

BA892 X2

FM MOD ULE

RD A5802

Y1

32.768KHz

+3.3V

ANT

.

D805

U1

UTX

RX: 136-17 4MHz

TX: 136- 174MHz

136~174MHz

65~108MHz

PB8 PB9

+5V

D200,D201

DA 221,1SS372

Q204

DT C114EE

U205

M4890

AUDIO A MP

PB15

Q802

RQ A0009

FIN AL AMP D RIVE AMP

APC

BAT T

PC9/PA

5T

UTX

URX

U503

NJM2904

SW

Q504

PA7

RT1N
141U

TONE

Q801

2SK3078

+5V

SW

Q502

DT A

144EE

FM A UDI O

W200A

VOLU ME

MI C SW

MIC MOD

U206

SG M4517

SW

Q505

DT C

144EE

AF

Q803

2SC3356

RF AMP

5T

RF AMP

HE4226

5RV

Q807

+3.3V

RF I N

AF SW

U201

SG M4517

RF OU T

PA11

Block Diagram

FT-4VR / FT-4VE

S521

3M3

TXCO

DS 500
LCD

X200

13.000MH z

+3.3V

PA12

PA15

COM0~3

SEG 0~34

+5V

3M3

OSC 13. 0MHz

U200

RD A1846S

RF MODULE

(LNA, MIX, IF, RSSI ,

SQ, AF C, CTCSS/DCS,

FM MOD EM, VCO,

LOOP FI LTER, VOX)

PA

VOX DET

SQ

PA7

5T

5TV

AUDI O

TONE

DC SW

U202

SG M4157

PB10, PB11,PB12

S500~S 509

S513~S 520

KEY MATRI X

DC SW

Q203

DT A

123JE

BLU E(B-RX)

FQC

3.3V REG.

PC13

SCL

J501

LCD D RIVE

+3.3V

D508

RED (TX)

PB13

SDA

GR EEN(A-RX)

PC14

GD32 F101CBT6

MICROPRO CESSOR

PTT

PC15

U500

D503

LCD BA CK LIG HT

S511

F/W

PA13

Q506

2SC

1623

S512

S510

MONI

EMERG ENCY

PB0

PA14

+3.3V

PA14

GND

PA13

PD1

URX

PB7
PB8
PB9

PA11
PA15

D504~D507

UTX

EEPROM

U504

AT24C128R M

+3.3V

PB4
PA7
PA8
PB5
PB6

PD0

SW

SD A

SCL

KEY BACK LI GHT

J500

IDE-INT ERFACE

U203

ME6206-33M

3.3V REG.

U501

ME6206-33M

5V R EG.

U502

ME6118A5 0

BATT1

W200B

POWER SW

BATT

D205
PROTECTOR

BAT

7.4V

FT-4XR/XE/VR/VE Technical Supplement

PB6

5RV

DC SW

Q205

DT C

114EE

Q202
DT A

114EE

PB5

3M3

+3.3V

SW

MK200

MIC

Q206

DT A

123JE

PD1

PTT DET

+3.3V

+3.3V

PB14

+5V

PB7

Block Diagram - 3