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5

SAFETY CHECKS 

Important Note!!!

 Do the following safety checks after servicing this unit. 

1.  Remove all the externally connected test equipment and wires before testing the unit. 
2.  Use the safety test circuit as shown below. 
3.  Plug the power cord or unit to be tested into the test receptacle. 
4.  Switch the unit being tested to ON or PLAY. 
5.  Connect external jack/terminal contact VTVM across a 1k resistor in the test circuit.  Set the meter to 

a high (150V AC) scale to avoid meter damage and then touch the points with the test probe. 
If the meter reading indicates less than 3 volts on all test points, set the meter to a low (3V AC) scale 
and repeat the test. 

6.  Any reading greater than 0.2 volt indicates a potential shock hazard.  If this occurs, determine the 

cause of the leakage, correct the problem, and repeat the safety test. 

ALIGNMENT AND ADJUSTMENT 

SERVICE ADJUSTMENT 

Lubrication

The mechanical parts are factory coated with a thin coat of light grease and should not require further 
lubrication.  If a light grease is applied, be careful not to get any grease on the play/record head or erase 
head, hubs, pulleys, tapes reels, drive belts, or switches.  Use a good lubricant such as Silicon Lube G331L 
or Lubricate (00). 

Service Check 

Before aligning the mechanism, wipe off any accumulated dirt with denatured alcohol. Wipe around parts 
where the tape contacts and around all rotating parts. Drive belts are specially processed. Do not clean 
them with alcohol.

8

Содержание BX900U

Страница 1: ...Model BX900U CONTENTS PAGE Specifications 1 6 Block Diagram 7 Safety Checks 8 9 Wiring Diagrams 10 Schematic Diagrams 11 12 Printed Circuit Boards 13 14 Exploded View 15...

Страница 2: ...ion at Max Volume 22 5KHz Dev Distortion at Max Volume 75KHz Dev 90MHz 10 90MHz 25 6dBAudio Fidelity Low Freq Hz 100 150 High Freq KHz 4 5 3 8 3dB Limiting Sensitivity 90MHz dB 30 35 Distortion at Ref...

Страница 3: ...CD 1at Speaker Output 100Hz dB 1KHz dB 45 40 10KHz dB S N Ratio Input Filter Dynamic Range Initial Reading Time TCD 782 dB 45 TCD 782 Sec TCD 782 Sec 10 Access Time TCD 782 First Track Sec 8 Last Trac...

Страница 4: ...ROCK 20Hz dB 100Hz dB 1K dB 10K dB 20K dB CLAS 20Hz dB 100Hz dB 1K dB 10K dB 20K dB POP 20Hz dB 100Hz dB 1K dB 10K dB 20K dB JAZZ 20Hz dB 100Hz dB 1K dB 10K dB 20K dB FLAT 20Hz dB 100Hz dB 1K dB 10K...

Страница 5: ...2 3 Max Power O P at Headphone 90MHz MW FM 75KHz Dev 1KHz CD OdB 1KHz AUX IN 500mV 1KHz BLUETOTH 784 OdB 1KHz dB 3 90KHz dB 3 784 OdB 1KHz dB 3 0 OdB 1KHz dB 3 0 784 OdB 1KHz dB Bass Boost 100Hz dB 12...

Страница 6: ...ormal Limit Test Data 1 2 3 10 T H D Power O P 500MV Input W 8 7 8 Stereo Separation 180MV Input dB 38 35 Min Hum 180MV Input mV 0 7 2 Max Hum mV S N dB 55 50 Total Harmonic Distortion 0 5 1 Test Cond...

Страница 7: ...nse Speaker Output CD 1 1Khz at Reference Output OdB 63Hz dB 100Hz dB 6 3 1KHz dB 10KHz dB 6 3 20KHz dB THD at Standard Output at 10dB 1KHz 1 Separation CD 1at Speaker Output 100Hz dB 1KHz dB 45 40 10...

Страница 8: ...BLOCK DIAGRAM 7...

Страница 9: ...AC scale and repeat the test 6 Any reading greater than 0 2 volt indicates a potential shock hazard If this occurs determine the cause of the leakage correct the problem and repeat the safety test ALI...

Страница 10: ...5 ms 4 Test Mode Play Sony CD Type 3 Track 1 Press FF Fast Forward Until A B as Figure Bellow SCOPE DC POSITION A B Figure A B FOCUS BIAS ADJUSTMENT 1 Test Point VC RFO 2 Test Disc Sony Test CD Type 3...

Страница 11: ...WIRING DRAWING 10...

Страница 12: ...SCHEMATIC DIAGRAMS 11...

Страница 13: ...SCHEMATIC DIAGRAMS 12...

Страница 14: ...SCHEMATIC DIAGRAMS 13...

Страница 15: ...PRINTED CIRCUIT BOARDS 14...

Страница 16: ...PRINTED CIRCUIT BOARDS 15...

Страница 17: ...16...

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