What does the circled r: ® mean in the Chart Supplement (A/FD)? You can see it here to the left of SOCAL APP/DEP CON:
According to the Chart Supplement (formerly the A/FD) legend:
APP CON—Approach Control. The symbol ® indicates radar approach control
DEP CON—Departure Control. The symbol ® indicates radar departure control.
The FAA has different approach facilities classifications, a TRACON has radar but others don't. So you should see this symbol when the approach/departure services are provided by a TRACON or other radar facility.
According to this legend for the A/FD, the symbol indicates that the approach/departure control has radar. This means that ATC can more accurately locate, track, and provide guidance to pilots.