342 / | HD | COMMUNICATIONS: DIRECTIVE RADIO WAVE SYSTEMS AND DEVICES (E.G., RADAR, RADIO NAVIGATION) |
118 | DF | DETERMINING DISTANCE {11} |
134 | DF | .~ With pulse modulation {4} |
139 | DF | .~.~ Combined with determining direction {3} |
142 | .~.~.~ With CRT display {2} | |
143 | DF | .~.~.~.~> Plural |
144 | DF | .~.~.~.~> PPI type |