| 968 / | HD | HOROLOGY |
| 925 | DD | VISUAL TIME- OR DATE-INDICATION MEANS [G04G 9/00] {9} |
| 926 | | .~ Transmission of control signals [G04G 9/00] {1} |
| 927 | DD | .~.~> Using coded signals (synchronization combined with automatic setting at regular intervals, e.g., by coded signals, etc. subclass 920) [G04G 9/00B2] |