Pioneer qt 74 service manual

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pioneer qt 74 service manual

Extracted text from pioneer qt 74 service manual (Ocr-read)


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GT-74

CONTENS

SPECIFICATIONS .......................................
PARTS IDENTIFICATION .................................
DISASSEMBLY

3.1 Deck Panel ........................................
3.2 Amplifier Panel .....................................
3.3 Bottom Panel ......................................
3.4 Wooden Cabinet ....................................

TROUBLE-SHOOTING ....................................
SCHEMATIC DIAGRAMS, P.C. BOARD PATTERNS AND PARTS LIST

5.1 Miscellaneous Parts ...................................
5.2 Equalizer Switch Assembly (RWX-OOS) .....................
5.3 Amplifier-A Assembly (RWF-OOS) ........................
5.4 Amplifier-B Assembly (RWF-004l ........................
5.5 Oscillator Assembly (RWA-OOZ) ..........................
5.6 Power Supply Circuit Assembly (RWR-OZOl ..................
5.7 REC Switch Assembly (RWX-002) ........................
5.8 Mode Switch Circuit Assembly (RWX-001) ..................
5.9 Muting Switch Assembly (RWX-OO3) ......................

MECHANICAL ADJUSTMENTS

6.1 Check in Play Mode ..................................
6.2 Checking Supply Reel Back Tension (PLAY) .................
6.3 Adjusting the Take-up Torque (PLAY) .....................
6.4 Check in Fast Forward Mode ............................
6.5 Adjusting the Fast Forward Back Tension ...................
6.6 Adjusting the Fast Forward Take-up Torque .................
6.7 Adjusting the Pinch Roller Pressure .......................
6.8 Pause Lever Adjustment ...............................
6.9 Adjustment of Tape Travel Height ........................

TAPE HEAD ADJUSTMENTS ...............................

RECORDING BIAS ADJUSTMENTS

8.1 Oscillator Output Level Check and Adjustment ...............
8.2 Bias Current Adjustment ...............................
8.3 Bias Trap Coil Alignment ..............................

PLAYBACK AMPLIFIER ALIGNMENT

9.1 Playback Equalization Check ............................
9.2 Equalizer Adjustment .................................
9.3 Level Meter Calibration ................................

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