| 968 / | HD | HOROLOGY |
|
| 524 | DD | DRIVING MECHANISMS FOR CLOCKS BY MASTER CLOCKS [G04C 13/00] {2} |
| 525 | DD | .~ Circuit arrangements; electric clock installations [G04C 13/02] {5} |
| 534 | DD | .~.~ Master clocks [G04C 13/04] {4} |
| 535 |  | .~.~.~ Monitoring or controlling master clock or system with more than one master clock, e.g., for switching over to standby motor or power system, etc. [G04C 13/04B] {2} |
| 536 | DD | .~.~.~.~> By using devices similar to slave clocks [G04C 13/04B2] |
| 537 | DD | .~.~.~.~> Systems in which slave clocks function as master clocks for other slave clocks (synchronization of independently driven clocks subclass 506; setting subclass 498) [G04C 13/04B3] |