Abstract: A portable voice capture device having an orientable arm comprising a first leg and a second leg, the first leg and the second leg having different orientations, the first leg of the first arm comprising a first differential linear array of microphones, a directivity of the first differential linear array being arranged for improved sensing of voice from a user, the second leg of the arm comprising a second differential linear array of microphones, a directivity of the second differential linear array being arranged for improved sensing of noise from a different than the direction of said sensed voice, and a noise reduction circuit for providing a voice signal with reduced noise, based on the output of the first array and on the output of the second array.

Abstract: A portable voice capture device comprising: an orientable arm with a first differential array of microphones comprising at least one pair of microphones, the directivity of said first array being arranged for sensing voice from a first direction depending on the orientation of said arm; a second differential array of microphones comprising at least one pair of microphones, the directivity of said second array being arranged for sensing noise from a second direction different from the first direction; a noise reduction circuit for providing a voice signal with reduced noise, based on the output of said first array and on the output of said second array.

Abstract: A wellstring assembly comprising a tubular first wellstring part with a passageway; a second wellstring part co-operating with the first wellstring part; and a releasable wellstring-interconnecting means for selectively interconnecting the first and second wellstring parts; an auxiliary tool for manipulating the second wellstring part, which auxiliary tool can pass along the passageway in the first wellstring part to the second wellstring part, comprising a tool-connecting means for selectively connecting the auxiliary tool to the second wellstring part, and an operating means for operating the wellstring-interconnecting means.

Abstract: Surfaces of a downhole tool, e.g. a drill bit, a reamer shoe or a stabilizer, are protected by at least temporarily fixing a super-hard material (6) to the surfaces of the down-hole tool, and spray fusing a binding material (2) around the super-hard material to permanently bind the super-hard material to the down hole tool.