346 / | HD | RECORDERS |
45 | DF | PLURAL-FUNCTION RECORDER, DISTINGUISHABLE RECORDINGS {4} |
49 | DF | .~ Plural markers and single record receiver {1} |
50 | DF | .~.~ With dotting, printing, or punching marker {5} |
52 | DF | .~.~.~ Markers under selective control of element normally discrete from recorder {3} |
55 | .~.~.~.~ Time-driven record receiver |