User manual JVC XM-PX50WT

[. . . ] XM-PX50WT SERVICE MANUAL PORTABLE MINIDISC PLAYER XM-PX50WT UB Area Suffix Hong Kong Contents Safety Precautions Important for laser products Attention when MD pick up is exchanged Disassembly method Adjustment method 1-2 1-3 1-4 1-5 1-11 1-12 1-12 1-13~25 Maintenance of laser pickup Replacement of laser pickup Description of major ICs COPYRIGHT 2001 VICTOR COMPANY OF JAPAN, LTD. No. 20902 Jan. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits. [. . . ] Remove the screw D, E, F and G attaching the chassis assembly respectively. Disengage the three joints e of the bottom case and the battery holder. Remove the chassis assembly and the jack cover at once. Tab d Chassis assembly Side arm (R) Joint e B Battery lid Joints e Fig. 5 Battery lid Eject unit C C Chassis assembly Fig. 6 D Chassis assembly Joint e G Joints e Bottom case E Battery holder F Fig. 7 1-6 XM-PX50WT Removing the main board and the battery holder (See Fig. 8 and 9) CN301 CN401 Battery holder Soldering f Prior to performing the following procedures, remove the MD door assembly, the holder assembly and the chassis assembly. ATTENTION: Before disconnecting the flexible wire extending from the pickup, make sure to solder the short circuit round to prevent damage to the pickup. Solder the short circuit round of the flexible wire on the main board. Disconnect the flexible wires from connector CN301 and CN401 on the main board. Remove the one screw H attaching the main board. Remove the main board with the battery holder . Short circuit round CN401 Headphone jack assembly Main board Soldering f Short circuit round H Fig. 8 Unsolder the four soldered parts f retaining the main board and the battery holder. ATTENTION: When reassembling, connect the flexible wire extending from the pickup to the connector on the main board and unsolder the short circuit round. CN301 Fig. 9 Headphone jack assembly CN601 Battery holder Removing the headphone jack assembly (See Fig. 10) Prior to performing the following procedures, remove the MD door assembly, the holder assembly, chassis assembly and the main board. Disconnect the flexible wire extending from the headphone jack from connector CN601 on the main board. Main board Fig. 10 1-7 XM-PX50WT <Removal of the MD mechanism section> Prior to performing the following procedures, remove the MD door assembly, the holder assembly, the chassis assembly and the main board. Slit washer Worm gear Shaft holder Soldering g J I Removing the spindle motor (See Fig. 11) 1. Unsolder the part g on the flexible wire extending from the underside of the Chassis assembly to the spindle motor. ATTENTION: Do not spill flux on the gear and others. attaching the spindle Chassis assembly Part i Part h Pickup unit Spindle motor Fig. 11 Lead screw Removing the pickup unit (See Fig. 11) ATTENTION: When handling the Pickup unit, touch the parts marked in Fig. 13 only. Remove the slit washer and the worm gear from the underside of the Chassis assembly. Remove the screw J attaching the shaft holder and draw out the shaft (lead screw). Pull out the Pickup unit and the lead screw while disengaging the part h and i. K Lead spring Pickup Fig. 12 Removing the pickup (See Fig. 12 and 13) Touch these parts only. ATTENTION: When handling the pickup unit, touch the parts marked in Fig. 13 only. Pull out the shaft from the pickup. Fig. 13 1-8 XM-PX50WT Removing the feed motor (See Fig. 14) 1. Peel off the adhesive tape j on the flexible wire on the underside of the feed motor. Unsolder soldering k connecting the flexible wire to the feed motor. Remove the two screws L attaching the feed motor. (2) Life of the laser diode When the life of the laser diode has expired, the following symptoms will appear. The level of RF output (EFM output:ampli tude of eye pattern) will below. Replacement of laser pickup Turn off the power switch and, disconnect the power cord from the ac outlet. Replace the pickup with a normal one. (Refer to "Pickup Removal" on the previous page) Is the level of RFOUT under 0. 35Vp-p?YES O. K NO Replace it. Plug the power cord in, and turn the power on. [. . . ] voltage input for laser power intensity setting Ground Ope. amp input terminal Serial data input terminal Shift clock input terminal Latch input terminal Stand by setting terminal F0 count setting terminal Reference voltage output terminal EQ IF setting terminal BPF3T IF setting terminal Power supply Pin No. Symbol I/O WBLADJ TE CSLED SE ADFM ADIN ADAGC ADFG AUX FE ABCD BOTM PEAK RF RFAGC AGCI NC NC ADDC NC TEGC RFO MORFI MORFO I/O O O O I O O O O O O O I I/O I O I O 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 I I O I I I I I I I O I O I I I I I I O I/O I/O - 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Function BPF3T IF setting terminal Tracking error signal output terminal Sled error signal LPF capacitor connect terminal Sled error signal output terminal ADIP FM signal output terminal ADIP signal completer input terminal ADIP AGC capacitor connect terminal ADIP binary signal output I3 output/temp. signal output Focus error signal output Reflection light q'ty signal output for main beam servo detector RF/ABCD bottom-hold signal output RF/ABCD peak-hold signal output RF equalizer output RFAGC capacitor connection RFAGC input Non connect Non connect ADIP amp. feedback circuit capacitor connection Non connection TE amp. output Groove RF signal AC-coupled input Groove RF signal output 1-21 XM-PX50WT IC-PST3421U-X(IC504):System reset 1. Pin layout VOUT 1 4 VSS 2. Pin function Pin No. Symbol VOUT VDD NC VSS Function Reset signal output terminal Power supply terminal Non connect VSS terminal VDD 2 3 NC 1 2 3 4 3. Block diagram VDD 2 1 VOUT Vref VSS 4 TK11223BMC-X (IC961) : Regulator 1. [. . . ]