公开(公告)号：DE1563538A1

公开(公告)日：1970-03-05

申请号：DE1563538

申请日：1966-01-22

Applicant: MOTOROLA INC

Inventor： STEVENS DAME JOHN ,  SALTZBERG THEODORE

IPC: B66C13/40 ,  G08C19/14 ,  H04Q7/02

Abstract: 1,066,160. Selective signalling. MOTOROLA Inc. Nov. 11, 1965 [Jan. 25, 1965], No. 47909/65. Heading G4H. In a remote control system, for example for a crane, a sequence of eight pairs of tones, each pair being referred to as a " group," is transmitted, and the system is characterized in that of the two tones in each group one indicates the position that the group should occupy in the sequence, whereby a check, can be made that the tones have been received correctly. As described the tones are chosen from two sets of tones, a set of eleven (numbered 1 to 11) highfrequency tones and a set of seven (numbered 12 to 18) low-frequency tones and each group of tones comprises one from each set. The sequence of tones transmitted is divided into an address portion, Fig. 2, comprising the first three groups, and a main control portion, comprising the last five groups. The particular address shown in Fig. 2 is represented by low-frequency tones 1 to 3 (top row of Figure) each being associated with either tone 12 to 13 (bottom row) of the high-frequency tones. Also, as shown, the serial order of the main control groups (4 to 8) is determined by low-frequency tones 14 to 18 each of which is associated with one highfrequency tone chosen in accordance with the control to be effected. The entire sequence of eight tone groups is continuously repeated. At the receiver filters separate the tones and the following checks are made upon each sequence of eight tone groups before it has any effect: (1) the address is checked, (2) the serial order of the tone group is checked, and (3) each tone group is checked to see that it contains one high-frequency and one low-frequency tone.