New Wireless Telephony Device

Radio Record, Volume IV, Issue 34, 6 March 1931, Page 5

New Wireless Telephony Device

To Prevent Eavesdropping ee JTSVENTORS are still busy trying to find a way to prevent confidential messages sent by wireless . telephony from being intercepted by unauthorised listeners, The vice-president of the Bell Telephone Laboratories has recently described a method for "scrambling" speech before it reaches the ether, so that anyone who’ succeeded in picking up the signals en route would hear no more than an unintelligible jumble _of sounds, For instance, the words "telephone company" are transposed into "play-o-fine crink-a-rope," so long as they are travelling through space. In order to convert them into their original form a special "unscrambling" device is necessary, and this is, of course, installed only at the authore ised receiving station. Some time ago it was proposed to use "secret?" wireless for broadcast» ing special items of particular inter» est to a limited number of. subscribers, who would each be provided with the necessary equipmgnt for reconvert> ing the "jumbled" message into clear language. The project has not yet been. car ried into practice, although it has cer tain possibilities which may cause if to be revived in some 4srm or other in the future.