Brand: SONY
Category: Audio
Document Type: Parts/Service
Language: EN
Parts/Service for CDP-791/X111ES
Uploaded: Nov. 21, 2025, 7:52 p.m.
This manual provides detailed service information for the SONY CDP-791/X111ES Compact Disc Player. It includes specifications, safety checks, disassembly instructions, electrical block checking procedures, diagrams, exploded views, and a comprehensive parts list. Key sections cover AC leakage testing, laser diode handling, and adjusting operating voltage. Troubleshooting is guided by detailed schematics and block diagrams, with specific component descriptions and part numbers provided for repair and maintenance.
Troubleshooting and error codes
| Problem | Troubleshooting Steps |
|---|---|
| AC leakage | Perform safety check. Ensure exposed metal parts do not exceed 0.5 mA leakage to earth ground or between metal parts. Use a commercial leakage tester, battery-operated AC milliammeter, or measure voltage drop across a resistor (limit 0.75 V). |
| Laser diode emission check | Observe from more than 30cm away from the objective lens. Handle optical pick-up block with care due to electrostatic breakdown potential. |
| S Curve Check | Connect oscilloscope to TP (FEO) on BD board. Connect between TP (FES) and TP (VC). Check for symmetrical S curve between A and B, with a peak-to-peak level of 3 ± 1 Vp-p. Ratio of A:B or B:A should be more than 10:7. |
| RF Level Check | Connect oscilloscope to TP (RF) on BD board. Confirm clear waveform and correct RF signal level. |
| E-F Balance Check | Connect TP (ADJ) to ground and TP (TES) to TP (VC). Connect oscilloscope to TP (TEO) on BD board. Check for symmetrical waveform relative to OV, with a level of 2 ± 1 Vp-p. |
| RF PLL Free-run Frequency Check | Connect frequency counter to TP (PCK) on BD board. Turn power on. Confirm reading is 3218MHz. |