968 / | HD | HOROLOGY |
844 | DD | APPARATUS FOR MEASURING UNKNOWN TIME INTERVALS BY ELECTRIC MEANS (timing devices for clocks or watches for comparing the rate of the oscillating member with a standard subclass 769; radar systems, analogous systems G01S 9/00; measuring frequency G01R 23/00; measuring phase angle G01R 25/00) [G04F 10/00] {5} |
845 | .~ Using oscillators with passive electric resonator, e.g., lumped LC, etc. (subclasses 846, 847, and 849 take precedence) [G04F 10/02] |