Yamaha 501 Owner's Manual page 11

Scanning discs to search for a desired disc (or to check discs on the disc tray)
When the DISC SCAN button is pressed while this unit is
stopped, this unit will play an early part of each disc in turn.
Each disc is played for 8 seconds.
If, during this play, you hear a disc that you want to listen to in
entirely, press the DISC SCAN button once again or press the
PLAY button to cancel this function. The unit will enter into the
normal play mode.
Notes
During this play, the disc tray numbers flash on and off on
the display. Every time the play of a disc is finished, the
corresponding tray number is changed from flashing to
lighting.
Selecting time displays
You can select any of the four time displays by pressing the TIME display mode-select button.
Elapsed time of the track now playing
5DISC
2 3 4 5 6 7 8 9 10 1 1 1 2
Remaining time of the track now playing
5DISC
2 3 4 5 6 7 8 9 10 1 1 1 2
Note
The remaining time will not be displayed if the track
number is 21 or higher.
REMAIN
There might be cases that you will hear no sound during disc
scan. An example of this would be if the disc being played
has a long blank space between tracks.
Total remaining time on the disc
5DISC
2 3 4 5 6 7 8 9 10 1 1 1 2
TIME
Total disc play time
5DISC
2 3 4 5 6 7 8 9 10 1 1 1 2
DISC
SCAN
TOTAL
REMAIN
TOTAL
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