Nad 300 Service Manual

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CONTENTS 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. SPECIFICATIONS DISASSEMB LY I NSTRUCTI ONS 7 DIAL STRINGING DETAIL ALIGNMENT AND CHECK POINTS ALIGNMENTPROCEDURES ....9- CHANGING POWER LINE VOLTAGES TROUBLESHOOTI NG TUNER FRONT-END OO36TUNERBOARD ...2O 5027 PRE-AMPLIFIER BOARD ..,.. 21 6038 MAIN AMPLIFIER BOARD 7105 SWITCH BOARD 7110 DOLBY NR BOARD 7118 DOLBY FM CALIBRATION BOARD BO25 POWER SUPPLY BOARD ...... 25 9025 TONE AMPLIFIEB BOARD .... 26 ELECTRICAL PARTS LIST 27 - 36 M ISCE LLAN EOUS PARTS LIST PAGE 3- 6 7 I 12 13 18 19 2223 24 25 37 38 39 BLOCK DIAGRAM INTERNAL VIEW OF INTEGRATED CIRCUIT SCHEMATIC DIAGRAM SEPARATE SHEET 2

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1. SPECIFICATIONS 4.5. 6. A. FM SECTION 1. FM Tuning Range *Adjustment for tuning prohibited below 87.5 MHz in West Germany 2. Dial Calibration Accuracy 90 & 106 MHz 98 MHz IHF Sensitivity at 90, 98 & 106 MHz Noise and Distortion: -30 dB lmage Rejection at 98 MHz lF Rejection at 90 MHz AM Rejection at 98 MHz at 30% AM & 100% FM Simultaneous Modulation, 100 - 20,000 pV Antenna lnput Limiter Sensitivity at - 1 dB Below Maximum Audio Total Harmonic Distortion at 98 MHz TAPE OUT (at 400 Hz lOOo/o Modulation, 1,000 pV lnput) Spurious Response at 98 MHz Antenna lnput: 3 pV OSC 2nd 206.7 MHz 1/2lF 103.35 MHz 10. lF Bandwidth,6 dB down Antenna lnput: 100pV 1 1 . lF Bandwidth, 50 dB down Antenna lnput: 100 pV 12. Signal-to-Noise Ratio 100% Mod., 1 mV lnput 13. Capture Ratio 1,000 prV, MONO lnput 14. Output Voltage Stereo and Mono, 4OO H2,100% Mod. TAPE-2 OUT 15. Alternate Channel Selectivity (lH F) Antenna lnput: 100 pV 16. Muting Threshold B. FM MPX SECTION 1. Stereo Separation at 98 MHz (Antenna lnput: 1,000 pV) 100 Hz 1 kHz 10 kHz Hl-BLEND on, at 1 kHz 2. Total Harmonic Distortion at 98 MHz Stereo, 1 mV Antenna lnput 1 kHz and/or 500 Hz 100% Mod., at REC OUT 3. Automatic Stereo Threshold 4. Residual 19 kHz & 38 kHz at 98 MHz, 1 mV lnput 5. Stereo Frequency Response 40 - 10,000 Hz 6. 19 kHz Pilot Signal Dev. to Activate 7. 9. NOMINAL LIMIT *87.7-108 r 150 t'100 1.8 83 90 t 200 x2OO 2.8 73 75 0.8 60 B-20 1.2 5-16 45 t1 7 1.6 o.25 250 600 70 1.2 1.0 75 10 o.4 10 50 0.6 80 80 200 800 65 2 35 40 28 13 30 33 22 1 313 UN IT MHz kHz kHz pV dB dB dB pV o/ /o dB dB kHz kHz dB dB dB pV dB dB dB dB o/ /o sV dB dB o//o F.

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Symptom Cause and RemedY J) Defective capacitor C2O2, C208 or C222' Replace the defective caPacitor. Defective transistor TR 101, 1 R1O2, TR 1 03 coil L101, L104 of tuner f ront-end. Replace the defective comPonent. Faulty lead-in. Repair or rePlace the lead in, K) L) n lmproper adjustment Readjust f2O1, VR301 and VR303a, b' (Refer to MPX ALIGNMENT on page 1 1') Defective transistor TR301, T8302, TR303 or lC lC3O1, lC3O2 of Turner Board 0036' Replace the defective comPonent. Variable resistor V R301 defective. Replace the variable resistor. Variable resistor VR303a, b defective. Replace the defective variable resistor' B) C) D) 12 Poor multiPlex seParation. 13) Stereo indicator lamp does not light' A) Defective indicator lamP PL9. Replace the lamP. lmproper adjustment of VR301 and VR302 of 0036 TUNER BOARD. Make readjustment. (Refer to MPX ALIGNMENT on page 1 1') Defective lC3O1 or R835 of 0036 TUNER BOARD. Rep lace defective comPonent. lf volume both L and R channels not enough: Front End defective, or faulty IFT T201 or diode D207, D2OB of 0036 TUNER BOARD or faulty C313, lC3O1 or 1C302 of 0036 TUNER BOARD. Locate and replace the defective component' lf sound of one channel not enough: Defective lC3O2 of 0036 TUNER BOARD' Replace the lC. B) c) A) B) 14 FM volume not sufficient' 15) AM does not operate' A) Damaged lC4O1 of Tuner Board 0036' Replace. B) Defective Coil L401 ,T4O1or Ceramic Filter CF4O1 of 0036 Tuner Board' Replace the defective comPonent' C) Selector switch S1 defective. Repair or rePlace the switch. D) Defective Tuning Gang. Replace.