Yaesu ft 450 schematic

HF/50 MHz TRANSCEIVER

FT-450

Technical Supplement

Introduction

This manual provides technical information necessary for servicing the FT-450 HF/50 MHz Transceiver.

Servicing this equipment requires expertise in handling 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.

EH024H90A

VERTEX STANDARD CO., LTD.

4-8-8 Nakameguro, Meguro-Ku, Tokyo 153-8644, Japan

VERTEX STANDARD

US Headquarters

10900 Walker Street, Cypress, CA 90630, U.S.A.

YAESU EUROPE B.V.

P.O. Box 75525, 1118 ZN Schiphol, The Netherlands

YAESU UK LTD.

Unit 12, Sun Valley Business Park, Winnall Close Winchester, Hampshire, SO23 0LB, U.K.

VERTEX STANDARD HK LTD.

Unit 5, 20/F., Seaview Centre, 139-141 Hoi Bun Road, Kwun Tong, Kowloon, Hong Kong

VERTEX STANDARD (AUSTRALIA) PTY., LTD.

Normanby Business Park, Unit 14/45 Normanby Road Notting Hill 3168, Victoria, Australia

Two PCB layout diagrams are provided for each doublesided circuit board in the Transceiver. Each side of is referred to by the type of the majority of components installed on that side (“leaded” or “chip-only”). In most cases one side has only chip components, and the other has either a mixture of both chip and leaded components (trimmers, coils, electrolytic capacitors, ICs, etc.), or leaded components only.

While we believe the technical information in this manual to be correct, VERTEX STANDARD 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.

Specifications Exploded View & Miscellaneous Parts Block Diagram Connection Diagram Alignment Board Unit (Schematics, Layouts & Parts)

RF-IF Unit PANEL Unit CNTL Unit PA Unit TUNER Unit ATU-450 (Option)

Specifications

General

Rx Frequency Range: 30 kHz - 56 MHz (operating)

160 - 6 m (specified performance, Amateur bands only)

Tx Frequency Ranges: 160 - 6 m (Amateur bands only) Frequency Stability: ±1 ppm/hour (@+25 °C, after warmup) Operating Temperature Range: –10 °C ~ +50 °C Emission Modes: A1A (CW), A3E (AM), J3E (LSB, USB), F3E (FM), F2D (DTMF TONE) Frequency Steps: 10 Hz (SSB & CW), 100 Hz (AM & FM) Antenna Impedance: 50 Ohms, unbalanced Power Consumption: Rx (signal present) 1.5 A

Tx (100 W) 22 A

Supply Voltage: DC 13.8 V ± 10% Dimensions (WxHxD): 9” x 3.3” x 8.5” (229 x 84 x 217 mm) Weight (approx.): 7.9 lb (3.6 kg)

Transmitter

Power Output: 100 watts (25 watts AM carrier) Modulation Types: J3E (SSB): Balanced,

A3E (AM): Low-Level (Early Stage), F3E (FM): Variable Reactance

Maximum FM Deviation: ±5.0 kHz / ±2.5 kHz Harmonic Radiation: Better than –60 dB (160 - 10m Amateur bands)

Better than –70 dB (6m Amateur band)

SSB Carrier Suppression: At least 60 dB below peak output Undesired Sideband Suppression: At least 60 dB below peak output Audio Response (SSB): Not more than –6 dB from 400 to 2600 Hz 3rd-order IMD: –31 dB @14 MHz 100 watts PEP Microphone Impedance: 600 Ohms (200 to 10 kOhms)

SPECIFICATIONS-1

Receiver

Circuit Type: Double-conversion superheterodyne Intermediate Frequencies: 67.899 MHz / 24 kHz Sensitivity (IPO “OFF”, ATT: OFF): SSB (2.4 kHz, 10 dB S+N/N)

0.25 µV (1.8 - 2.0 MHz)

0.25 µV (3.5 - 30 MHz)

0.20 µV (50 - 54 MHz)

AM (6 kHz, 10 dB S+N/N, 30 % modulation @400 Hz)

2.00 µV (1.8 - 2.0 MHz)

2.00 µV (3.5 - 30 MHz)

1.00 µV (50 - 54 MHz)

FM (BW: 15 kHz, 12 dB SINAD)

0.50 µV (28 - 30 MHz)

0.30 µV (50 - 54 MHz)

There is no specification in frequency ranges not listed.

Squelch Sensitivity: SSB/CW/AM (IPO “OFF”, ATT: OFF) 2.50 µV (1.8 - 30 MHz)

1.00 µV (50 - 54 MHz)

0.32 µV (28 - 30 MHz)

0.16 µV (50 - 54 MHz)

There is no specification in frequency ranges not listed.

Selectivity (–6/–60 dB): Mode –6 dB –60 dB

CW 0.5 kHz or better 2.0 Hz or less SSB 2.2 kHz or better 4.5 kHz or less AM 6 kHz or better 20 kHz or less FM 15 kHz or better 30 kHz or less FM-N 9 kHz or better 25 kHz or less

Image Rejection: 80 dB or better (160 - 10m Amateur bands)

65 dB or better (6m Amateur band)

Maximum Audio Output: SSB/CW 1.5 W into 8 Ohms with 10% THD

AM/FM 0.6 W into 8 Ohms with 10% THD

Audio Output Impedance: 4 to 16 Ohms (8 Ohms: nominal) Conducted Radiation: Less than 4000 µµW

Specifications

Specifications are subject to change, in the interest of technical improvement, without notice or obligation, and are guaranteed only within the amateur bands.

SPECIFICATIONS-2

Specifications

Note

SPECIFICATIONS-3

Exploded View & Miscellaneous Parts

RA0899500 LCD HOLDER

RA0931100 (X2 pcs) LIGHT SHEET

RA089970A LIGHT GUIDE

RA0940000 (X4 pcs) TAPE

RA0900000 INTER CONNECTOR

RA089960A SPONGE (LCD)

LCD

RA089980C REFLECTOR SHEET

RA094710A SHEET

PANEL Unit

RA0900000 INTER CONNECTOR

RA0951800 (X 2pcs) PAD

RA0898800 SHIELD COVER (CTRL)

RA089870A RUBBER PACKING

T9207114A WIRE ASSY

T9207120A WIRE ASSY

CNTL Unit

RA089840A SP NET

RA0924900 SPONGE (SP)

M4090066 SPEAKER

RA0898600 SP HOLDER

PA Unit

P1091172 RF CONNECTOR

RA0898200 TOP CASE

S6000427 CLAMP

T9207202A WIRE ASSY

RA0925700 (X2 pcs) SPONGE (CHASSIS)

T9207398A WIRE ASSY

RA0898900 FAN COVER

M2090048 FAN

RA0898000 CHASSIS

No. VXSTD P/N Decription Qty.

U31306007 OVAL HEAD SCREW M3X6B 20

U20420007 BINDING HEAD SCREW M4X20B 4

U24306002 BIND HEAD TAPTITE-B M3X6NI 20

U03310002 SEMS SCREW ASM3X10NI 9

U04410002 SEMS SCREW HSM4X10NI 1

U24108002 BIND HEAD TAPTITE-B M2X8NI 9

U20306002 BINDING HEAD SCREW M3X6NI 5

U30305002 FLAT HEAD SCREW M3X5NI 7

VXSTD P/N Decription Qty.

Q0000074 BLADE FUSE 25A 1

M3090122A MICROPHONE MH-67A8J W/CLIP 1

T9023725 DC CABLE 04P 25AX2 3000MM 1

TUNER Unit ATU-450 (Option)

T9318299 WIRE ASSY (GRN 250 TMP/TMP)

RA0901500 SHIELD CASE ASSY

RA0900800 KNOB

RA0900700 KNOB

RA0900100 KNOB MAIN ASSY

RA0900400 RUBBER RING

U91408007 HEX SOCKET SCREW

RA090090A RUBBER KNOB

RA0900800 KNOB

R6144801 NUT

R3135000A WASHER

R0136380 COIL SPRING

RA089920A PANEL ASSY

RA0900800 KNOB

Q9000709A ROTARY ENCODER

RA090100A RUBBER KNOB

T9207114A WIRE ASSY

PANEL Unit

T9318244A WIRE ASSY (GRA 250 TMP/TMP)

S4000043 (X4 pcs) CASE LEG

T9207114A WIRE ASSY

RF-IF Unit

T9318049 WIRE ASSY (GRN 500 TMP/TMP)

ANT TUNER ASSY

RA0898500 BOTTOM CASE

T9207410 WIRE ASSY

T9318300 WIRE ASSY(GRA 320 TMP/TMP)

RA0951800 PAD

TUNER Unit

RA0901700 SHIELD PLATE

RA0901800 SPONGE RUBBER

FT-450 Technical Supplement

Exploded View-1

Exploded View & Miscellaneous Parts

Note

Exploded View-2

FT-450 Technical Supplement

Block Diagram

BLOCK DIAGRAM-1FT-450 Technical Supplement

Connection Diagram

CONNECTION DIAGRAM-1 FT-450 Technical Supplement

Alignment

Introduction and Precautions

The following procedures cover adjustments that are not normally required once the transceiver has left the factory. However, if a problem occurs during normal operation due to component failure; realignment may be required after the faulty components have been replaced.

We recommend that authorized Vertex Standard Technicians, who are experienced with the circuitry and fully equipped to repair and align our products, perform repairs. If a fault is suspected, contact the selling dealer for instructions regarding repair. Authorized Vertex Standard Technicians have the latest information to align all circuits and make complete performance checks to ensure compliance with factory specifications after repairs.

Those who undertake the following alignments are cautioned to proceed at their own risk. Problems caused by unauthorized attempts at realignment are not covered by the warranty policy.

Vertex Standard must reserve the right to change circuits and alignment procedures in the interest of improved performance, without notifying owners.

Under no circumstances should any alignment be attempted unless the normal functions and operation of the transceiver are clearly understood, the cause of the malfunction has been clearly identified and all faulty components replaced. The need for realignment should be determined to be necessary.

The following test equipment (and a thorough familiarity with its correct use) is necessary for correct alignment. Most steps do not require all of the equipment listed. The interactions of some adjustments may require that several adjustments be performed in a sequence. Do not attempt to perform only a single step unless it is clearly isolated electrically from all other steps. Have all test equipment ready before beginning, and follow all of the steps in a section in the order they are presented.

Required Test Equipment

 RF Signal Generator  AF Signal Generator  Spectrum Analyzer good to at least 1 GHz.  Frequency Counter  SINAD Meter  RF Millivoltmeter  Digital DC Voltmeter (high-Z, 1 M-Ohm/V)  DC Voltmeter  DC Ammeter (20 A)  Ohmmeter  50-Ohm Dummy Load (100 watts)  16.6-Ohm Dummy Load (100 watts)  In-Line Wattmeter (100 watts, 50-Ohm)  Linear Detector  RF Coupler  4-Ohm AF Dummy Load (3 watts)

Alignment Preparation & Precautions

A 50-ohm RF Dummy load and in-line wattmeter must be connected to the "ANT" jack in all procedures that call for transmission, except where specified otherwise. Correct alignment is not possible with an antenna.

After completing one step, read the following step to determine whether the same test equipment will be required. If not, remove the unneeded test equipment before proceeding (except the dummy load and wattmeter).

Correct alignment requires that the ambient temperature be maintained constant between 68 °F ~ 86 °F (20 °C ~ 30 °C). When the transceiver is brought into the shop from a hot or cold environment, it should be allowed time to come to room temperature before alignment. Also, the test equipment must be thoroughly warmed up before beginning.

Whenever possible, alignments should be made with oscillator shields and circuit boards firmly affixed in place.

Note: Signal levels in dB referred to in this proce-

dure are based on 0 dBµ = 0.5 µV (closed circuit).

ALIGNMENT-1

Alignment

Reference Frequency

 Connect the Frequency Counter to TP2001 on the

RF-IF-Unit.

 Adjust X2001 so that the Frequency Counter read-

ing is 22.625 MHz ±10 Hz.

2nd Local Carrier Output Level

 Connect the RF millivoltmeter to TP2009 on the

RF-IF-Unit.

 Adjust T2017 on the RF-IF-Unit for maximum

deflection on the RF millivoltmeter (more than 25 mVrms).

PLL VCV Voltage

 Connect the Digital DC voltmeter (high-Z) to

TP2006 on the RF-IF-Unit.

 Set the [MODE] switch to FM.  Referring to the table below, adjust the listed com-

ponents for the required voltage, or confirm that the correct voltage is present on each frequency listed.

VFO-A FREQUENCY

13.499 MHz

0.030 MHz

29.999 MHz

13.500 MHz

44.499 MHz

30.000 MHz

55.999 MHz

44.500 MHz

ADJUST / CONFIRM

Adjust L2065

Confirm

Adjust L2066

Confirm

Adjust L2067

Confirm

Adjust L2068

Confirm

DC VOLTMETER

5.2 V ± 0.1 V At least 0.5 V

5.2 V ± 0.1 V At least 0.7 V

TX IF Circuit (SSB/CW)

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Disconnect the TMP plug from J2002 on the RF-

IF-Unit, and then connect the RF millivoltmeter and 50 Ohm dummy load to J2002.

 Inject the 1 mV, 1 kHz audio signal to pin 5 of

MIC jack.

 Set the transceiver to 7.000 MHz, USB mode.  Press the PTT button; adjust T2018, T2019, T2021,

and T2022 on the RF-IF-Unit for maximum deflection on the RF millivoltmeter.

 Disconnect the RF millivoltmeter and 50 Ohm

dummy load from J2002 on the RF-IF-Unit, then re-connect the TMP plug to J2002.

RX IF Circuit (SSB/CW)

 Set the following controls as indicated:

[IPO]: OFF [ATT ]: OFF [RF GAIN] knob: Fully clockwise

 Connect the AF millivoltmeter and 4 Ohm

dummy load to the EXT SPKR jack.

 Connect the RF Signal Generator to the "ANT"

jack, and then set the output level to 0 dBµV at the 51.995 MHz.

 Set the transceiver to 51.995 MHz in the CW

mode.

 Adjust T2020 on the RF-IF-Unit for maximum

deflection on the AF millivoltmeter.

RX IF Circuit (FM)

 Set the following controls as indicated:

[IPO]: OFF [ATT ]: OFF [RF GAIN] knob: Fully clockwise

 Connect the SINAD meter and 4-Ohm dummy

load to the EXT SPKR jack.

 Connect the RF Signal Generator to the "ANT"

jack, and then set the RF Signal Generator to

51.995 MHz at the level of 0 dBµV, ± 3.0 kHz deviation with a 1 kHz audio tone.

 Set the transceiver to 51.995 MHz in the FM mode.  Adjust T2021 and T2022 on the RF-IF-Unit for

maximum deflection on the SINAD meter.

ALIGNMENT-2

J2002

Alignment

T2020

T2021

T2018

TP2006

TP2001TP2009 T2017

X2001 T2019

T2022

RF-IF UNIT ALIGNMENT POINTS

L2066

L2065

L2067

L2068

ALIGNMENT-3

Alignment

PA Unit

Preparation

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Cut the lead of L5008 on the PA Unit.  Set VR5401, VR5402, VR5403, and VR5404 on the

PA Unit to fully counter clockwise position.

 Set the transceiver to 14.150 MHz in the USB

mode.

Pre-Drive Stage Idling Current

 Disconnect the jumper plug from J5003 on the

PA Unit, and then connect the DC ammeter to J5003.

 Press the PTT button; adjust VR5401 on the PA

Unit so the DC ammeter reading is 100 mA ± 10 mA.

 Release the PTT button.

Drive Stage Idling Current

 Disconnect the jumper plug from J5004 on the

PA Unit, and then connect the DC ammeter to J5004.

 Press the PTT button; adjust VR5402 on the PA

Unit so that the DC ammeter reading is 0.5 A ± 50 mA.

 Release the PTT button.  Press the PTT button; adjust VR5403 on the PA

Unit so the DC ammeter reading is 1.0 A ± 50 mA.

 Release the PTT button.

Final Stage Idling Current

 Connect the DC ammeter to the lead of L5008.  Press the PTT button; adjust VR5404 on the PA

Unit so the DC ammeter reading is 1.0 A ± 100 mA.

 Release the PTT button.  Press the PTT button; adjust VR5405 on the PA

Unit so the DC ammeter reading is 2.0 A ± 100 mA.

 Release the PTT button.

Concluding

 Re-connect the jumper plugs to J5003 and J5004,

and then solder the lead of L5008.

CM Coupler Balance

 Connect the DC voltmeter between TP5430 (+

lead) on the PA Unit and Chassis (- lead).

 Set the transceiver to 29.200 MHz in the CW

mode.

 Press the PTT switch; adjust TC5400 on the PA

Unit for minimum deflection on the DC voltmeter (less than 0.1 V).

 Release the PTT switch.

ALIGNMENT-4

Alignment

TC5400

L5008

TP5430

VR5403

PA U NIT ALIGNMENT POINTS

J5003

VR5401

J5004

VR5402VR5404 VR5405

ALIGNMENT-5

Alignment

Software Adjustment

Preparation

 Set the VFO frequency for each band as indicated:

OPERATING BAND

General Band

1.8 MHz Band

3.5 MHz Band 7 MHz Band

14 MHz Band 21 MHz Band 28 MHz Band 50 MHz Band

 Set the following controls as indicated:

[IPO] button: OFF [ATT ] button: OFF [AGC] button: AUTO [SHIFT] knob: 12-o'clock position [AF GAIN] knob: 12-o'clock position [RF GAIN] knob: Fully clockwise MODE: CW CONTOUR: OFF NOTCH: OFF DNR: OFF

S-meter Adjustment

 Connect the RF Signal Generator to the "ANT"

jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Select the appropriate "Alignment Parameter"

using the [DSP/SEL] knob per the chart below, then set the RF Signal Generator output to each level, and adjust the [MAIN DIAL] knob for the corresponding S-meter deflection.

ALIGNMENT PARAMETER

SMADJ0 SMADJ1 SMADJ2 SMADJ3 SMADJ4 SMADJ5 SMADJ6

SMADJ

RF SIGNAL GENERATOR

1.200 MHz, 32 dBµ

1.900 MHz, 12 dBµ

3.750 MHz, 12 dBµ

7.150 MHz, 12 dBµ

14.175 MHz, 12 dBµ

21.255 MHz, 12 dBµ

28.850 MHz, 12 dBµ

52.000 MHz, 12 dBµ

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

FREQUENCY

1.200 MHz

1.900 MHz

3.750 MHz

7.150 MHz

14.175 MHz

21.255 MHz

28.850 MHz

52.000 MHz

S-METER

S-1 (3 dots) S-1 (3 dots) S-1 (3 dots) S-1 (3 dots) S-1 (3 dots) S-1 (3 dots) S-1 (3 dots) S-1 (3 dots)

ALC Adjustment

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "I-ALC1".

 Press the PTT switch, then rotate the [MAIN DIAL]

knob for 140 W ± 10 W on the Wattmeter. Note the alignment value which is displayed on the frequency display area of the LCD.

 Release the PTT switch.  Rotate the [DSP/SEL] knob to select the align-

ment parameter "I-ALC2".

 Press the PTT switch, then rotate the [MAIN DIAL]

for 110 W ± 5 W on the Wattmeter. Release the PTT switch.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "I-ALC3".

 Rotate the [MAIN DIAL] knob to set an alignment

value to same value, which was noted in the previous step ("I_ALC1").

 Press and hold in the [F] button for 2 seconds to

save the new setting and exit from the alignment mode.

Power Adjustment (100 W)

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Select the appropriate "Alignment Parameter"

using the [DSP/SEL] knob per the chart below, and adjust the [MAIN DIAL] knob for the corre- sponding Wattmeter deflection while pressing the PTT switch.

ALIGNMENT PARAMETER

1PO100 2PO100 3PO100 4PO100 5PO100 6PO100 7PO100

WATTMETER

100 W ±2 W 100 W ±2 W 100 W ±2 W 100 W ±2 W 100 W ±2 W

90 W ±2 W

100 W ±2 W

ALIGNMENT-6

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

Alignment

Power Adjustment (50 W)

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Select the appropriate "Alignment Parameter"

using the [DSP/SEL] knob per the chart below, and adjust the [MAIN DIAL] knob for the corre- sponding Wattmeter deflection while pressing the PTT switch.

ALIGNMENT PARAMETER

1PO 50 2PO 50 3PO 50 4PO 50 5PO 50 6PO 50 7PO 50

WATTMETER

50 W ±2 W 50 W ±2 W 50 W ±2 W 50 W ±2 W 50 W ±2 W 50 W ±2 W 50 W ±2 W

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

Power Adjustment (20 W)

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Select the appropriate "Alignment Parameter"

using the [DSP/SEL] knob per the chart below, and adjust the [MAIN DIAL] knob for the corre- sponding Wattmeter deflection while pressing the PTT switch.

ALIGNMENT PARAMETER

1PO 20 2PO 20 3PO 20 4PO 20 5PO 20 6PO 20 7PO 20

WATTMETER

20 W ±2 W 20 W ±2 W 20 W ±2 W 20 W ±2 W 20 W ±2 W 20 W ±2 W 20 W ±2 W

Power Adjustment (10 W)

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack. Press and hold in the [ATT/IPO], [NB], and [AGC] buttons, while turning the radio on, to enter the alignment mode. Select the appropriate "Alignment Parameter" using the [DSP/SEL] knob per the chart below, and adjust the [MAIN DIAL] knob for the corre- sponding Wattmeter deflection while pressing the PTT switch.

ALIGNMENT PARAMETER

1PO 10 2PO 10 3PO 10 4PO 10 5PO 10 6PO 10 7PO 10

WATTMETER

10 W ±1 W 10 W ±1 W 10 W ±1 W 10 W ±1 W 10 W ±1 W 10 W ±1 W 10 W ±1 W

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

Power Adjustment (5 W)

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Select the appropriate "Alignment Parameter"

using the [DSP/SEL] knob per the chart below, and adjust the [MAIN DIAL] knob for the corre- sponding Wattmeter deflection while pressing the PTT switch.

ALIGNMENT PARAMETER

1PO 5 2PO 5 3PO 5 4PO 5 5PO 5 6PO 5 7PO 5

WATTMETER

5 W ±1 W 5 W ±1 W 5 W ±1 W 5 W ±1 W 5 W ±1 W 5 W ±1 W 5 W ±1 W

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

ALIGNMENT-7

Alignment

TX Gain Adjustment

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Connect the Audio Generator to pin 5 of the MIC

jack (pin 7: GND), then set the output level to 1 mV @1 kHz.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

ALIGNMENT PARAMETER

TXG1H TXG2H TXG3H TXG4H TXG5H TXG6H TXG7H TXG1L TXG2L TXG3L TXG4L TXG5L TXG6L TXG7L

WATTMETER

50 W ±10 W 50 W ±10 W 50 W ±10 W 50 W ±10 W 50 W ±10 W 50 W ±10 W 50 W ±10 W

10 W ±2 W 10 W ±2 W 10 W ±2 W 10 W ±2 W 10 W ±2 W 10 W ±2 W 10 W ±2 W

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

AM Carrier Level Adjustment

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Set the [MODE] switch to "AM".  Rotate the [DSP/SEL] knob to select the align-

ment parameter "AM-CAR".

 Press the PTT switch, then rotate the [MAIN DIAL]

knob for 25 W±2 W on the Wattmeter.

 Release the PTT switch.  Press and hold in the [F] button for 2 seconds to

save the new setting and exit from the alignment mode.

ALC Meter Adjustment

 Connect the 50-Ohm Dummy Load and Wattme-

ter to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "ALCM L".

 Press the PTT switch, then press the [STO] but-

ton.

 Connect the Audio Generator to pin 5 of the MIC

jack (pin 7: GND), then set the output level to 4 mV @1 kHz.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "ALCM H". Press the PTT switch, then press the [STO] button.

 Press and hold in the [F] button for 2 seconds to

save the new setting and exit from the alignment mode.

Reverse ALC Adjustment

 Connect the 16.6-Ohm Dummy Load (parallel

connections of the three 50-Ohm Dummy Loads) to the "ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "1-RALC".

 Press the PTT switch, then rotate the [MAIN DIAL]

knob for 50 W on the PO meter of the FT-450.

 Release the PTT switch.  Rotate the [DSP/SEL] knob to select the align-

ment parameter "2-RALC".

 Press the PTT switch, then rotate the [MAIN DIAL]

knob for 50 W on the PO meter of the FT-450.

 Release the PTT switch.  Rotate the [DSP/SEL] knob to select the align-

ment parameter "3-RALC".

 Press the PTT switch, then rotate the [MAIN DIAL]

knob for 50 W on the PO meter of the FT-450.

 Release the PTT switch.  Rotate the [DSP/SEL] knob to select the align-

ment parameter "50RALC".

 Press the PTT switch, then rotate the [MAIN DIAL]

knob for 50 W on the PO meter of the FT-450. Release the PTT switch. Press and hold in the [F] button for 2 seconds to save the new settings and exit from the alignment mode.

ALIGNMENT-8

Alignment

Voltmeter Adjustment

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Adjust the DC Power Supply voltage is exactly

13.8 V.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "VM-ADJ".

 Press the [STO] button.  Press and hold in the [F] button for 2 seconds to

save the new setting and exit from the alignment mode.

ATAS Controller Adjustment

 Connect the Digital DC voltmeter (high-Z) to the

"ANT" jack.

 Press and hold in the [ATT/IPO], [NB], and [AGC]

buttons, while turning the radio on, to enter the alignment mode.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "ATAS DN".

 Press the [STO] button, then rotate the [MAIN

DIAL] knob for 8.0 V on the DC Voltmeter.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "ATAS BK".

 Press the [STO] button, then rotate the [MAIN

DIAL] knob for 9.5 V on the DC Voltmeter.

 Rotate the [DSP/SEL] knob to select the align-

ment parameter "ATAS UP".

 Press the [STO] button, confirm that the DC Volt-

meter reading is more than 10.5 V.

 Press and hold in the [F] button for 2 seconds to

save the new settings and exit from the alignment mode.

ALIGNMENT-9

Alignment

Note

ALIGNMENT-10

RF-IF Unit

Circuit Diagram

FT-450 Technical Supplement

RF-IF-1

RF-IF Unit

Note

RF-IF-2

FT-450 Technical Supplement

Parts Layout (Side A)

A B C D E

RF-IF Unit

2SK520 (K41)

(Q 2018,Q 2021)

UPC4572G2

(Q2060)

SPM5001

(Q 2061)

HSB88WS

(D 2034)

2SK302Y (TY)

(Q2026)

2SK210 (YG)

(Q2033, 2034,

2035, 2036)

LM2904PWR

(Q2037, 2039, 2043)

3SK151GR

(Q2040, 2049, 2050)

ADF4001BRUZ

(Q2013)

CD4094BPWR (Q2044, 2045)

2SC5415E (EA)

(Q2002, 2028)

2SC3357 (RK)

(Q2020)

2SD2211 (DQR)

(Q 2057)

PDTC144EE (08)

(Q2001, 2007, 2008,

Q2009, 2010, 2024, Q2029, 2030, 2031, Q2032, 2047, 2051)

AD9833BRMZ

(Q2004)

MC2848

(D2007, 2053)

DAN235U

(D 2052)

HZM7.5NB3

(D2031, 2055)

HZM5.6NB2

(D2063)

HZM27WA

(D 2061)

DAP236U

(D2032, 2033)

BU2507FV

(Q2046)

RF2713

(Q2055, 2056)

2SA1602A (MF)

(Q2048)

ISA1602AM1(Lot.9-)

(Q2048)

TC7S04FU (E5)

(Q2006, 2015)

2SC2812NL6

(Q2003, 2041)

2SC2714Y

(Q2005, 2011, 2012,

2014, 2016, 2017, 2019,

2022, 2023, 2025)

2SC3356 (R24)

(Q2027)

2SA1365

(Q2052)

2SC4154 (E)

(Q2062)

2SJ125D

(Q 2058)

FT-450 Technical Supplement

RF-IF-3

+ 49 hidden pages

Yaesu ft 450 schematic

Introduction

Contents

Specifications

General

Transmitter

Receiver

Exploded View & Miscellaneous Parts

Block Diagram

Connection Diagram

Alignment

Required Test Equipment

Alignment Preparation & Precautions

Reference Frequency

2nd Local Carrier Output Level

PLL VCV Voltage

TX IF Circuit (SSB/CW)

RX IF Circuit (SSB/CW)

RX IF Circuit (FM)

RF-IF UNIT ALIGNMENT POINTS

PA Unit

PA U NIT ALIGNMENT POINTS

Software Adjustment

RF-IF Unit

Circuit Diagram

Parts Layout (Side A)