178 / | HD | TELEGRAPHY |
2 R | DF | SYSTEMS {21} |
3 | DF | .~ Automatic {4} |
4 | DF | .~.~ Printing {1} |
4.1 R | .~.~.~ Remote control {3} | |
4.1 A | DF | .~.~.~.~> Radio-controlled |
4.1 B | DF | .~.~.~.~> Called station identification answer back system |
4.1 C | DF | .~.~.~.~> Revertive signaling |