11. These SPAD indicators are placed beyond the protecting stop signal and are normally unlit. 12. Stop signals are used to protect platforms or block sections.13. DeCurtis had been cited twice, in 1986 and 1989, for running through stop signals . 14. But IBM's electrical fuses stop signals in an unusual way. 15. Italian news reported suggested the express might have ignored a stop signal at Castello station. 16. A particular signal box may control one or more stop signals on each running line. 17. In addition to twice running stop signals , DeCurtis derailed once and missed a station once. 18. By contrast, in methanogenic archaea it was not possible to identify any unambiguous UAG stop signal . 19. Junction stop signals were provided with two main signal heads, one mounted higher than the other. 20. Propagating through its channel the stop signal latches the flip-flops of the start signal's delay line.
