Jvc QLA 2 Service Manual

Page 2

OL-AZ
No. 2444

Contents

Page
1. Specifications ........................................................ 2
2. Service Precautions ..................................................... 3
3. Features ............................................................ 3
4. "How to Operate" (Names and Functions) ..................................... 3
5. Operation of Automatic Mechanism .......................................... 4
6. Block Diagrams
6-(1) Servomotor Control System ........................................ 5
G-(Z) ICSOZ Integrated Circuits and Waveforms ............................... 5
7. Troubleshooting
7-(1) Platter does not rotate ............................................ 6
7-(2) Platter rotates at high speed ........................................ 7
7-(3) Rotation is not locked to the crystal oscillator frequency ..................... 7
8. Cartridge Replacement .................................................. 8
9. Adjustment Procedures
Servomotor Control Section
9-(1) Power Supply Voltage Check ....................................... 8
942) Lock Adjustment ............................................... 8
Tonearm Section
9-(3) Overhang Adjustment ............................................ 9
9~(4) Tonearm Lifter Height Adjustment ................................... 9
9-(5) Auto-return (Lead-out) Adjustment ................................... 9
9-(6) Tracking Force Adjustment ........................................ 10
9-) Anti-skating Adjustment .......................................... 10
10. Lubrication .......................................................... 1 1
11.» Exploded Views and Parts List
11-(1) Cabinet and Mechanism Assembly .................................... 11
1142) Mechanism Base Assembly ......................................... 13
11-l3l Knob Base Assembly ............................................. 13
11-(4) Tonearm Assembly .............................................. 14
11-(5) Parts List with Specified Numbers for Designated Areas ...................... 14
12. Connection Diagram of TXX-124 ........................................... 15
13. TXX-124 Schematic Diagram .............................................. 16
14. TXX-124 Printed Circuit Board Ass'y and Parts List ............................... 17
15. Packing Materials and Part Numbers .......................................... 21
16. Accessories List ....................................................... 21
17. QL-AZ Schematic Diagram ................................................ 22
WARNING!

When replacing the parts marked with A , be sure to use the designated parts to ensure safety.

. marked on the rear panel or the chassis. The voltage selector switch accommodates up

CHECKING YOUR LINE VOLTAGE (For U.S. Military Market and Other Countries)
Before inserting the power plug, please check this setting to see that it corresponds
with the line voltage in your area. If it doesn't, be sure to adjust the voltage selector
switch to the proper setting before operating this equipment. The voltage selector
switch is located either on the set's on the chassis. Simply insert a screw driver into the
voltage selector switch and turn it in either direction while pressing slightly and in such
a way that desired voltage marked on the switch is positioned underneath the arrow

to three turns in either direction.