From inside (document excerpt):
User and Operator’s Manual for 1995, 1996, 1997, 1998 and 1999 Mercedes-Benz S-Class Becker Sound System 1692.
Contents
Radio Functions
5 Basic Controls
1 On/Off Switch, Volume Control
2 Anti-theft Indicator
3 BasslTreble Selector
4 Fader/Balance Selector
5 Bass, Treble, Fader,
Balance Control
2 Tuning
6 AM or FM Band
7 Weather Band (WB)
8 Station Memory Buttons
9 Seek Tuning
10 Scan Tuning
11 Manual Tuning
Display Panel
12 Band (AM/FMIWB)
13 Station Memory Location
14 Station Frequency
15 Stereo Mode
16 Cassette-in Indicator