Abstract: The invention relates to a device and process which utilize the Doppler effect for measurement of the performance of blasting operations, in particular to the measurement of face velocity. The measuring device comprises radiation generating and receiving means and a signal analyzing means.

Abstract: An apparatus for blasting comprises a series of electronically programmable detonators and an exploder, connected in series. The exploder communicates to the detonators at least programming and firing signals. The detonators are connected in such a way that programming signals will be received by a given detonator only when the adjacent detonator nearer to the signal output of the exploder has been programmed. This is preferably achieved by use of a connector associated with each detonator, the connector comprising a switching device which is operated by a logic element such that the logic element will operate on the switching device and allow signals to pass only when the detonator associated with that connector has been programmed.The apparatus permits the versatile and precise use of explosives, especially where large numbers of charges are involved.

Abstract: A method of detonating explosive charges for the breaking of rock and ore comprises the use of two sets of components, one set within the explosive charge and the other set at the surface of the explosive. The set within the exposive comprises a detonator, a first delay element and a passive energy storage device such as a capacitor. The second set which is able to communicate with the first comprises a power source, a second delay element and a means for receiving signals from a remote command source. In a preferred embodiment, the first delay element has a fixed delay and the second delay element has a programmable delay.The method permits of versatility and precision in the use of explosives, using relatively inexpensive components.