EasyManua.ls Logo

Yamaha TX-497 - Service Manual

Yamaha TX-497
32 pages
Print Icon
To Next Page IconTo Next Page
To Next Page IconTo Next Page
Loading...
SERVICE MANUAL
This manual has been provided for the use of authorized YAMAHA Retailers and their service personnel.
It has been assumed that basic service procedures inherent to the industry, and more specifically YAMAHA Products, are already
known and understood by the users, and have therefore not been restated.
WARNING: Failure to follow appropriate service and safety procedures when servicing this product may result in personal
injury, destruction of expensive components, and failure of the product to perform as specified. For these reasons,
we advise all YAMAHA product owners that any service required should be performed by an authorized YAMAHA
Retailer or the appointed service representative.
IMPORTANT: The presentation or sale of this manual to any individual or firm does not constitute authorization, certification or
recognition of any applicable technical capabilities, or establish a principle-agent relationship of any form.
The data provided is believed to be accurate and applicable to the unit(s) indicated on the cover. The research, engineering, and service
departments of YAMAHA are continually striving to improve YAMAHA products. Modifications are, therefore, inevitable and
specifications are subject to change without notice or obligation to retrofit. Should any discrepancy appear to exist, please contact the
distributor's Service Division.
WARNING: Static discharges can destroy expensive components. Discharge any static electricity your body may have
accumulated by grounding yourself to the ground buss in the unit (heavy gauge black wires connect to this buss).
IMPORTANT: Turn the unit OFF during disassembly and part replacement. Recheck all work before you apply power to the unit.
IMPORTANT NOTICE
100970
SERVICE MANUAL
BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . .19
PRINTED CIRCUIT BOARD . . . . . . . . . . . . . . . . . . .20
SCHEMATIC DIAGRAM . . . . . . . . . . . . . . . . . . .21–22
PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23–31
CONTENTS
TO SERVICE PERSONNEL . . . . . . . . . . . . . . . . . . . .2
SPECIFICATIONS /
. . . . . . . . . . . . . . . . . . . . 3
FRONT PANELS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
REAR PANELS . . . . . . . . . . . . . . . . . . . . . . . . . . . .4–5
INTERNAL VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
DISASSEMBLY PROCEDURES /
. . . . . . . . 6
ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . .7–11
12–15
IC DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
DISPLAY DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
AM/FM STEREO TUNER
TX-497
TX-497
2005 . All rights reserved.
This manual is copyrighted by YAMAHA and may not be copied or
redistributed either in print or electronically without permission.
05.09

Other manuals for Yamaha TX-497

Questions and Answers

  • N
    nathaniel21Aug 19, 2025
    Why is the FM stereo reception noisy on my Yamaha Tuner?
    • C
      cainjulieAug 19, 2025
      Noisy FM stereo reception on your Yamaha Tuner can occur if the transmitter is too far away or the antenna input is poor due to the characteristics of FM stereo broadcasts. Check the antenna connections and consider using a high-quality directional FM antenna. Alternatively, setting the TUNING MODE button to the manual tuning mode and using the manual tuning method might improve the reception.
  • J
    Jacob MillerAug 21, 2025
    What to do if the desired station cannot be tuned in with the automatic tuning method on Yamaha TX-497?
    • A
      angelaoliverAug 21, 2025
      If you can't tune into the desired station automatically on your Yamaha Tuner, it could be due to a weak signal. Try using a high-quality directional FM antenna. You can also try using the manual tuning method.
  • K
    Karen MackAug 23, 2025
    Why is the ST indicator flickering and the reception noisy on my Yamaha Tuner?
    • R
      Richard SnyderAug 23, 2025
      If the ST indicator flickers and the reception is noisy on your Yamaha Tuner, it might be due to insufficient antenna input. Use an antenna appropriate for the reception conditions in your area. Also, ensure the station is correctly tuned in.
  • M
    Melissa DeanAug 26, 2025
    Why can't I tune in previously preset stations on my Yamaha Tuner?
    • T
      Todd ParsonsAug 26, 2025
      If you can no longer tune in previously preset stations on your Yamaha Tuner, it might be because the power cord has been disconnected from the AC outlet or the unit has been turned off for more than one week. In this case, preset the stations again.
  • A
    Amanda MendozaAug 28, 2025
    How to fix occasional crackling noises on Yamaha Tuner?
    • E
      Edward FosterAug 28, 2025
      Occasional crackling noises on your Yamaha Tuner, especially in weak signal areas, may be due to noise from motors, thermostats, or other electrical equipment. To resolve this, position the FM antenna as high as possible, away from roads and digital or high-frequency equipment. Use a coaxial cable and attach a noise suppressor to the equipment causing the noise.
  • E
    eric77Aug 30, 2025
    What to do if I cannot tune in the desired station with the automatic tuning method on my Yamaha TX-497?
    • G
      George KellyAug 30, 2025
      If you cannot tune in the desired station with the automatic tuning method on your Yamaha Tuner, the signal might be weak, or the antenna connections might be loose. Tighten the AM loop antenna connections and orient it for the best reception. Also, try using the manual tuning method.
  • A
    Ashley WeberSep 1, 2025
    How to eliminate distortion on Yamaha Tuner?
    • M
      Mckenzie EvansSep 1, 2025
      If you experience distortion and cannot get clear reception even with a good FM antenna on your Yamaha Tuner, there may be multipath interference. Adjust the antenna position to eliminate this interference.
  • C
    Craig BarnesSep 4, 2025
    How to stop continuous crackling and hissing noises on Yamaha TX-497 Tuner?
    • C
      charleslloydSep 4, 2025
      Continuous crackling and hissing noises on your Yamaha Tuner can be caused by noise from lightning, fluorescent lamps, motors, thermostats, or other electrical equipment. Move the unit further away from digital or high-frequency equipment. Use an outdoor antenna and a ground wire. This may help, but it’s difficult to eliminate all noise.
  • M
    myersmaxSep 6, 2025
    Why is there no stereo effect even with a stereo broadcast on my Yamaha Tuner?
    • J
      johnsonrogerSep 6, 2025
      If you're not getting a stereo effect even with a stereo broadcast on your Yamaha Tuner, the TUNING MODE button might be set to the manual tuning mode. Press TUNING MODE repeatedly until “AUTO” lights up in the front panel display.
  • A
    ashley10Sep 8, 2025
    What to do if Yamaha Tuner fails to turn on?
    • M
      Mr. Scott HudsonSep 8, 2025
      If your Yamaha Tuner fails to turn on when the POWER button is pressed, ensure the power cord is firmly connected to the AC outlet. If it still doesn't turn on, and the unit has been exposed to a strong external electric shock, disconnect the power cord, plug it back in after 30 seconds, and then try using it normally.

Summary

Specifications

FM Section Specifications

Detailed technical specifications for the FM tuner section, including tuning range, sensitivity, and distortion.

MW Section Specifications

Detailed technical specifications for the MW tuner section, including tuning range, sensitivity, and distortion.

LW Section Specifications

Detailed technical specifications for the LW tuner section, including tuning range and sensitivity.

Audio Section Specifications

Technical specifications for the audio output level, impedance, and harmonic distortion.

General Specifications

Overall technical specifications including power supply, dimensions, weight, and available finishes.

Disassembly Procedures

Adjustments

FM Tuner Section Adjustments

Fine Discriminator Balance Adjustment

Procedure for fine adjustment of the discriminator balance.

Fine Monaural Distortion Adjustment

Procedure for fine adjustment of monaural distortion.

FM Tuner Section Adjustments - Continued

MW Tuner Section Adjustments

LW Tuner Section Adjustments

Japanese Adjustments Section

1. Before Adjustment

Preparation steps including waiting for stability and setting the tuning mode before starting adjustments.

Test Points and Measurement Diagrams

Discriminator Balance Adjustment

Procedure for discriminator balance adjustment using signal generators and meters.

Monaural Distortion Adjustment

Procedure for monaural distortion adjustment using signal generators and meters.

Stereo Distortion Adjustment

Procedure for stereo distortion adjustment using signal generators and meters.

FM Adjustment Procedures

Discriminator Balance

Initial adjustment for discriminator balance using FM signal generator.

Monaural Distortion

Initial adjustment for monaural distortion using FM signal generator.

Discriminator Balance Verification

Verification step for discriminator balance after adjustments.

Frontend IFT Adjustment

Procedure for adjusting the frontend IFT for optimal performance.

Stereo Distortion

Procedure for adjusting stereo distortion.

Monaural Distortion Verification

Verification step for monaural distortion.

Sensitivity Verification

Verification of tuner sensitivity at specified frequencies.

Separation Adjustment

Procedure to maximize stereo separation.

FM Adjustment Procedures - Continued

AM Adjustment Procedures

IC Data

Block Diagram

Printed Circuit Board Layouts (Side A)

Printed Circuit Board Layouts (Side B)

Schematic Diagram (Tuner)

Schematic Diagram (Operation)

Parts List

Tuner PCB Parts List

Tuner PCB Parts List (Continued)

Tuner & Operation PCB Parts List

Operation PCB Parts List

Yamaha TX-497 Specifications

U.K. and Europe models

Audio Output IconAudio Output
FM Output Level500 mV/2.2 kΩ
AM Output Level200 mV/2.2 kΩ
FM Section IconFM Section
Tuning Range87.50 to 108.00 MHz
Selectivity70 dB
Signal to Noise Ratio Mono75 dB
Signal to Noise Ratio Stereo70 dB
Harmonic Distortion Mono0.1%
Harmonic Distortion Stereo0.2%
Stereo Separation50 dB
AM (LW) Section IconAM (LW) Section
Tuning Range153 to 288 kHz
Usable Sensitivity400 µV/m
Selectivity32 dB
Signal to Noise Ratio50 dB
Image Response Ratio40 dB
Spurious Response Ratio50 dB
Harmonic Distortion0.3%
General IconGeneral
Power SupplyAC 230 V, 50 Hz

Other models

Audio Output IconAudio Output
FM Output Level900 mV/2.2 kΩ
AM Output Level150 mV/2.2 kΩ
FM Section IconFM Section
Tuning Range87.50 to 108.00 MHz
Image Response Ratio80 dB
Spurious Response Ratio70 dB
Harmonic Distortion Mono0.1%
Harmonic Distortion Stereo0.2%
Stereo Separation50 dB
AM Section IconAM Section
Tuning Range531 to 1611 kHz

U.S.A. and Canada models

FM Section IconFM Section
Tuning Range87.5 to 107.9 MHz
50 dB Quieting Sensitivity Mono1.55 µV
50 dB Quieting Sensitivity Stereo21 µV
Image Response Ratio40 dB
Spurious Response Ratio60 dB
Alternate Channel Selectivity85 dB
Signal to Noise Ratio Mono82 dB
Signal to Noise Ratio Stereo76 dB
AM Section IconAM Section
Tuning Range530 to 1710 kHz
General IconGeneral
Power SupplyAC 120 V, 60 Hz

Asia and General models

FM Section IconFM Section
Tuning Range87.5/87.50 to 108.0/108.00 MHz
50 dB Quieting Sensitivity Mono1.55 µV
50 dB Quieting Sensitivity Stereo21 µV
General IconGeneral
Power SupplyAC 110–120/220–240 V, 50/60 Hz

Australia model

General IconGeneral
Power SupplyAC 240 V, 50 Hz

China model

FM Section IconFM Section
50 dB Quieting Sensitivity Mono1.55 µV
50 dB Quieting Sensitivity Stereo21 µV
Image Response Ratio40 dB
Spurious Response Ratio60 dB
Signal to Noise Ratio Mono82 dB
Signal to Noise Ratio Stereo76 dB
General IconGeneral
Power SupplyAC 220 V, 50 Hz

TX-497

General IconGeneral
Power Consumption7 W
Dimensions435 x 86 x 271 mm
Weight3.2 kg

Related product manuals