Specifically, this disc contains a specific test track (usually track 3 or 4, depending on the service manual) that emits a signal. This signal is used to measure the Radio Frequency (RF) waveform—commonly referred to as the "eye pattern."
The Sony YEDS 18 disc is pressed to absolute perfection. Its physical pits are precisely the correct depth (approximately 0.11 microns) and have the exact reflectivity (approximately 70-80%). This means if your player cannot read the YEDS 18 correctly, the problem is the player, not the disc. Sony Test Disc Yeds 18
| Feature | Detail | | :--- | :--- | | | 3-702-021-01 (YEDS-18) | | Type | Aluminum reflective layer (Standard CD) | | Signal Content | 3 kHz sine wave (Test track) / Silence | | Reflectivity | 70% - 80% (Nominal) | | Eccentricity | < 50 µm (Extremely low) | | Compatibility | CD, CD-ROM, CD-R/RW readers (Early models) | Specifically, this disc contains a specific test track
Technicians use this disc to adjust four critical variables: This means if your player cannot read the