Sanyo DS31590 Service Manual

Also see for DS31590: Owner's manual

Contents

— 8 —SERVICE ADJUSTMENTS (Continued)MULTI-SOUND SECTION ADJUSTMENTSNote: Multi-Sound Section must be adjusted afterIC101 (Signal Processor), IC3401 (MTS Decoder),IC802 (EEPROM), or T131 (Sound I.F. transformer)is replaced.INPUT LEVEL ADJUSTMENT1. Turn off the receiver and disconnect the AC power cord(AC 120V line).2. Connect audio signal generator output (300 Hz,150 mVrms) to TP301 and ground.3. Ground TP21 with a short jumper lead.4. Connect voltmeter (RMS) to TP317 and ground.5. While pressing the Menu key, reconnect the AC powercord. The Service Menu will now appear.6. Select NO. 32 INP (Input Level) with the or key.7. Adjust the + or – key for a voltmeter reading of 400 ± 5%mVrms at TP317.STEREO VCO ADJUSTMENT8. Turn off the receiver and disconnect the AC power cord(AC 120V line).9. Remove signal generator from TP301 and voltmeterfrom TP317.10. Connect frequency counter to TP317 and ground.11. While pressing the Menu key, reconnect the AC powercord. The Service Menu will now appear.12. Select NO. 33 STE (Stereo VCO) with the or key.13. Adjust the + or – key for a frequency counter reading of15.734 ± 0.1 KHz at TP317.FILTER ADJUSTMENT14. Turn off the receiver and disconnect the AC power cord(AC 120V line).15. Remove frequency counter from TP317.16. Connect audio signal generator output (15.734 KHz, 100mVrms) to TP301 and ground.17. Connect voltmeter (RMS) to TP317 and ground.18. While pressing the Menu key, reconnect the AC powercord. The Service Menu will now appear.19. Select NO. 34 FIL (Filter) with the or key.20. Adjust the + or – key until voltage is at trap point.Voltage change in the filter adjustments is shown inFigure 7.SEPARATION ADJUSTMENT21. Turn off the receiver and disconnect the AC power cord(AC 120V line).22. Remove jumper lead from TP21, signal generator fromTP301 and voltmeter from TP317.23. Connect oscilloscope CH1 to TP317 and CH2 to TP318and ground.24. Connect an MTS TV/Stereo generator to antenna termi-nal.25. Select pilot, 300Hz audio frequency and Left modulatingsignal.26. While pressing the Menu key, reconnect the AC powercord. The Service Menu will now appear.27. Select NO. 35 LSP (Low Separation) with the or key.28. Adjust the + or – key for minimum low frequencies atTP317. (See Figure 8.)29. Select 4 KHz audio frequency and Right modulating signal.30. Select NO. 36 HSP (High Separation) with the or key.31. Adjust the + or – key for minimum high frequencies atTP318. (See Figure 8.)Repeat adjustments (steps 27–31) until no further decreasesin amplitude can be obtained.SAP VCO ADJUSTMENT32. Turn off the receiver and disconnect the AC power cord(AC 120V line).33. Remove oscilloscope from TP317 and TP318, and MTSTV/Stereo generator from antenna terminal.34. Connect frequency counter to TP317 and ground.35. Ground TP21 with a short jumper lead.36. Connect a 1 MΩ resistor between TP316 and ground.37. While pressing the Menu key, reconnect the AC powercord. The Service Menu will now appear.38. Select NO. 37 SPV (SAP VCO) with the or key.39. Adjust the + or – key for a frequency counter reading of78.67 ± 0.5 KHz at TP317.40. Press the MENU key to turn off the Service Menu display.PURITY AND CONVERGENCE ADJUSTMENTSPurity and Convergence have been aligned at the factory.No re-alignment is necessary.Figure 7. Filter AdjustmentFigure 8. Separation Adjustments