| 370 / | HD | MULTIPLEX COMMUNICATIONS | 
| 464 | DF | COMMUNICATION TECHNIQUES FOR INFORMATION CARRIED IN PLURAL CHANNELS {9} | 
| 480 | DF | .~ Combining or distributing information via frequency channels {11} | 
| 485 |  | .~.~ Subscriber carrier {2} | 
| 486 | DF | .~.~.~> Program distribution {1} | 
| 488 | DF | .~.~.~> Connecting filters |