JVC QL-A2 Service Manual

QL-A2
No. 2444
Contents
Page
1. Specifications 0... ec ee ee ee ee eee ee eee eee en eee ees 2
2: Service: Precautions: sos. oe Sieis5 Fae ae eek BE ee ace Reber e ee se Sw Senge lig) a Tee ial tile 3
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4. ‘How to Operate’ (Names and Functions) ......... 000. eee e tenes 3
5. Operation of Automatic Mechanism ... 2... 0 6 ce eee teenie ee 4
6. Block Diagrams
6-(1) Servomotor Control System .......0 2 2c ee ee eee ees 5
6-(2) {C802 Integrated Circuits and Waveforms .........2 0002 cect ene ener eee 5
7. Troubleshooting
7-(1) Platter does not rotate... 0... eee eee eee ener eee 6
7-(2) Platter rotates at high speed .. 1.2.2... ee cc ee et eens 7
7-(3) Rotation is not locked to the crystal oscillator frequency .........2 0+. ee ee ene 7
8. Cartridge Replacement .......... 0. cece eee ee ee ee eee tees 8
9. Adjustment Procedures
Servomotor Control Section
9-(1) Power Supply Voltage Check ......... :0 cece eee eee eee e eee 8
9:(2)' Lock: Akiuistenie nt 35.26: a5 55 Seite S55 ete cw ey oriasies ead Sey leer e sora SOUR ale eae Sa 8
Tonearm Section
9-(3) Overhang Adjustment ...... 0... 0c ec ee ee ee et ee tee eee 9
9-(4) Tonearm Lifter Height Adjustment ..--- 02-00 cece ee ens 9
9-(5) Auto-return (Lead-out) Adjustment... 2.0.60. eee teens 9
9-(6) Tracking Force Adjustment ............ 00. cece eee eee eee eee 10
9-(7) Anti-skating Adjustment .... 0.2... 00. eee eet eee 10
10: Lubrication =... iene ee tiie ees te eee ao Wie Wh, BAS a Rae Bee ee ee Se 11
11. Exploded Views and Parts List
11-(1) Cabinet and Mechanism Assembly ..........00 0 eee eee eee ee eee eee 11
11-(2) Mechanism Base Assembly ............. 0. eee eee ee eee te eens 13
11-(3) Knob Base Assembly... 2... 0... ccc ee eee een ee eens 13
11-(4) Tonearm Assembly .......0. 0.00 cece eee eee eee ee eee eee eee 14
11-(5) Parts List with Specified Numbers for Designated Areas........-.----0220200- 14
12. Connection Diagram of TXX-124 2.2... ce ee ee ee eee ene 15
13. TXX-124 Schematic Diagram .. 0... 06. ce eee ee ee eee eee 16
14. TXX-124 Printed Circuit Board Ass’y and Parts List... 2.2... ce ee ee 17
15. Packing Materials and Part Numbers ... 0... 0. eee ec ee eee ee ee ee eee ee 21
AG. Accessories EASE, <2. sic o.scechcecce eb sok, laa 8 aie ee es ese othe Soe pera ee ace & a ad 21
17. QL-A2: Schematic: Diagraint 22.55: euc ols aleca en tes a hee R) aca wee) le 8 Dew eee Bla eae Ss be 22
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
. marked on the rear panel or the chassis. The voltage selector switch accommodates up
to three turns in either direction.

JVC QL-A2 Specifications

General

Drive System	Direct Drive
Motor	DC servo motor
Speeds	33 1/3 and 45 rpm
Platter	Aluminum die-cast
Wow and Flutter	0.03% WRMS
Effective Length	220 mm
Overhang	15 mm
Tonearm	Static balance S-shaped tonearm