Jvc QLF 6 Service Manual
This is the 27 pages manual for Jvc QLF 6 Service Manual.
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Extracted text from Jvc QLF 6 Service Manual (Ocr-read)
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Contents Pages 1. Specifications ................................................................... 2. ServicePrecautions................................................................ Features....................................................................... 4. NamesofPartsandTheirFunctions..................................................... 5. Replacement Procedures (1) Stylus.................................................................. (2) Headshell ".....................................,............... (3) Cartridge................................................................ (4) Motor.................................................................. (5) HO/VODampingKnobs " '" 6 6. Lubrication (1) HO/VODampingMechanism .................................................. (2) Motor.................................................................. (3) FullyAutomaticMechanism................................................... 7. Adjustment Procedures (1) ~UARTZ LOCK/PITCH CONTROL Meter ........................................ (2) OuartzLockAdjustment ..................................................... 8 Tonearm Section (3) HeadsheliAngle "..... (4) TonearmElevator.......................................................... (5) Overhang ............................................................... (6) Lead-in................................................................. (7) Lead-out................................................................ (8) TrackingForce........................................................... (9) Anti-skating............................................................. (10) HO/VODamping ......................................................... 8. OL-F6BlockDiagram ............................................................. 9. Troubleshooting Charts (1) Platter does not rotate. ..................................................... (2) Platter rotates at high speed. ................................................. (3) Pitch Control operates abnormally. ............................................. 10. Exploded Views and Parts List 10-(1) Cabinet & Mechanism Assy .................................................. 10-(2) Mechanism Assy ......................................................... 10-(3) TonearmAssy........................................................... 11. Printed Circuit Board Ass y and Parts List 11-(1) MDC-938G ............................................................. 11- (2) TPS-206 ............................................................... 12. Accessories List ................................................................. 13. OL-F6 Schematic Diagram .......................................................... 14. PackingMaterialsandPartNumbers.................................................... 15. Parts List with Specified Numbers for Designated Areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Back page OL- No. 24641 -
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Specifications MOTOR SECTION (These specifications apply only to the quartz lock mode. Motor : Core less, DC type FG servomotor : Phase- locking to the quartz oscillator : Direct drive : 33-1/3 Servo system Drive system Speeds Fine pitch adjustable range Wow and flutter Signal-to-noise ratio Speed detection Starting torque Speed deviation Load characteristics Drift Power characteristics Temperature characteristics Platter TONEARM SECTION Type Effective arm length Overhang Weight range including headshell: :!: 6 % (at the pitch control mode) : 0. 025 % (WRMS) : More than 78 dB (DIN- : Frequency generator : More than 1. 2 kg-cm : Within 0. 002 % : 0 % (with 170 g total tracking force) : 0.0001 %/H : 0 % (:!: 10 V) : 0. 00005 %tc : 32.7 cm : Statically-balam;ed oil-damped tonearm : 233 mm : 15 mm : 13 - 20 g 24 g (when using the provided sub-counterweight) 2. Service Precautions . Be sure to use JVC standard parts. . When repairing the speed control circuit board con- nect the m938 G motor in order to prevent damage to the transistor used.in the platter drive section. . Be sure to adjust motor speed with the u nit level otherwise fluctuations which make adjustment impos- sible may occur. . When repairing circuit board with the heat sink re- moved, attach mobile heat-sink to prevent the tran- sistor temperature from rising.CARTRIDGE SECTION (Except for USA, Canada and U. Type : Moving magnet (MD-l025EB) Frequency response: 10 Hz - 25000 Hz Output : 3 mV (1 kHz) Channel separation: 25 dB (1 kHz) (using the test record TRS- : 47 - 100 k-ohms : 10 x 106 cm/dyne (dynamic) 30 x 106 cm/dyne (static) : DT-Zl EB , 0.3 x 0.7 mil. (diamond, elliptical) Optimum tracking force: 1.75 g :!: 0. 25 g GENERAL Power consumption DimensionsLoad resistance Compliance Stylus Weight Accessories EP adapter: 15W : Height 14. 2 cm (with closed cover) Width 45.6 cm Depth 40. 0 cm (Since the dimensions show only the design measurements, con- sideration is requ ired when installing the unit in a limited space such as a rack, etc. : 11 kg (without the packaging) Sub-counterweight: 1 Place the adapter on the center spindle when playing a record having a bigger diameter center hole such as a doughnut record. : 1 Design and specifications subject to change without notice. 3. Features . Newly developed oil-damped tonearm assures high trackability. Highly sensitive, new gimbal'support tonearm system. . Double-quartz servo circu it and high torque, non- resonance coreless motor give high reliability. . Extra- heavy aluminum diecast platter (2 kg including the mat, inertia 330 kg/cm Howling margin is greatly improved with the new super-compound (type-l) board used as the base. Operation buttons and controls are positioned at the front for easy operation. . NR- type headshell with minimum resonance is em- ployed. Moving-magnet cartridge with a elliptical stylus. Fine pitch control allows adjustment within:!: 6 % (approx. a half note). . Quartz lock/Pitch control meter for convenient speed check. Fully automatic mechanism. QL- No. 2464
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(3) Pitch Control operates abnormally. Pitch control functions incorrectly. Check for disconnected wire(s) in the meter whether VR1 is open or if the meter leads are disconnected.Check if R64 is dis- connected and whether X22 is open. Replace if necessary. 2. Meter deflects to positive side and remains there. Collector and emitter of X 18 are short-cir- cuited. Replace this transistor.Readjust and observe 14 -Is D6 or D7 short- circu ited? Replaced. Yes Disconnected or de- fective R 11. Replace.YesCheck if R52 is dis- connected. Replace if defective. Fig. 26The collector and emit- ter of X 19 are short- circuited. Replace this transistor .Readjust and observe.Check if R12 is dis- connected. Replace if disconnected. Check if R53 is dis- connected. Replace if so.Yes QL- No. 2464