Abstract: First and second data processing systems located at first and second sites are configured with the first data processing system having a primary memory unit at the first site and a mirror memory unit at the second site with the first and second sites coupled by a single-mode optical fiber. Fiber optic switches at the first and second sites can be reconfigured to coupled the mirror disc to the second data processing system with minimal delay.

Abstract: A coupling device (10) for coupling a detonator cap (20) with an unfixtured detonating cord (80, FIG. 3 ) after removing a shipping plug (41, FIG. 2 ), features a sleeve member (12) having a longitudinal sleeve bore (18) extending therethrough for receiving a detonator cap (20) therein. The detonator cap (20) extends to the transition end (22) of the sleeve member (12) so that the detonating cord (80) does not enter the sleeve bore (18). A nut member (14) has an aperture (24) for receiving the cord (80) and is secured to the sleeve member (12) with its aperture (24) aligned with the bore (18). A ferrule (16) is seated on the sleeve member (12) and grips the detonating cord (80) when the nut member (14) is secured onto the sleeve member (12).

Abstract: A signal transmission tube assembly includes a signal transmission tube, such as a coil of shock tube on a spool, having opposite terminal ends and containing a reactive material. The open terminal ends of the shock tube provide the sole exits for the signal generated therein and the sole entry points for contaminants. Sealing means seal both terminal ends of the signal transmission tube against escape from the assembly of the signal engendered by initiated reaction of the reactive material, and protects the interior of the signal transmission tube from contamination. The sealing means may be a releasable sealing means which can be actuated to release the transmission tube from it, thereby facilitating re-use of the sealing means. Further, the sealing means may comprise a surge chamber to relieve pressure engendered by reaction of the reactive material and thereby militate against rupture of the signal transmission tube and consequent release from the assembly of a signal.

Abstract: A coupling device (10) for coupling a detonator cap (22a, 22b) with a detonating cord (82) features a sleeve member (12) having a longitudinal bore (18) extending therethrough for receiving a detonator cap (22a, 22b) in one end and a detonating cord (82) in the other. The coupling device (10) includes a nut member (14) having an aperture for receiving the cord (82) and having a compression surface (34) for bearing against a compression portion defined below when the nut member (14) is secured onto the sleeve member (12). The nut member (14) may be secured to the sleeve member (12) with its aperture aligned with the bore (18). A compression portion (31) associated with the sleeve member (12) responds to pressure from the compression surface (34) of the nut member (14) for gripping a cord (82) when the nut member (14) is secured onto the sleeve member ( 12). Thus, a cord can be securely disposed in detonation signal transmission relation to a cap without having special coupling hardware, e.g.

Abstract: A transmission tube initiator comprises a body having a passageway formed therein for receiving and retaining an initiator charge. A holder holds a side of a transmission tube in close proximity to the charge. The charge provides an initiation signal which penetrates the transmission tube and initiates a reactive substance contained in the transmission tube.

Abstract: A transmission tube signal delay assembly comprising a delay element containing a shaped delay composition having a preselected combustion time from a first side of the delay element to a second side of the delay element; a first transition element adjacent to the delay element at the first side for transferring a transmission tube signal to the delay element; and a second transition element adjacent to the delay element at the second side for transferring a signal from the delay element to a transmission tube, each of the transition elements comprising a shaped transition composition.