| 摘要 |
1,212,749. Repeater systems. C.I.T.-COMPAGNIE INDUSTRIELLE DES TELECOMMUNICATIONS. 26 Nov., 1968 [27 Nov., 1967], No. 56129/68. Addition to 1,109,566. Heading H4R. In a pilot operated automatic volume control and faulty repeater locating system of the type described in Specification 1,109,566 in which each of the sections between adjacent repeaters utilizes a different pilot frequency for gain regulation of the respective sections, and the pilot frequencies of adjacent sections differ by the same amount so that the pilot frequencies vary in arithmetic progression along the line, and at each repeater the incoming pilot is mixed with the outgoing pilot to produce a signal of the same frequency in each station to be detected by a pilot filter of that frequency and used for gain regulation of that repeater, the whole system Fig. 3 is divided into two main sections in the first of which, up to station M, the pilot frequencies increase in arithmetic progression while in the second main section, from station M, the pilot frequencies decrease in arithmetic progression from the same value F 0 as the frequencies in the first main section increased. The respective pilot frequencies (F 0 +if) provide gain regulation over the individual repeater sections while the repeater M using the pilot frequency F 0 provides an overall regulation of the first main section while the pilot signal F p provides an overall regulation of the link from A to B. All the pilot signals generated are received and monitored at station B to provide a faulty repeater indication arrangement. |
