Data acquisition apparatus

Data communication and power supply system for downhole...

Data relay for casing mounted sensors, actuators and generators

Data relay system for instrument and controller attached to...

Data telemetry system for multi-conductor wirelines

Data transmission in pipeline systems

Data transmission system

Data transmission system for downhole logging tools

Data transmission system for logging tools

Data-fusion receiver

Device and method for transmitting information by electromagneti

Device for exploring an underground formation crossed by a horiz

Device for providing an electrically insulated connection...

Device for transmitting to the surface the signal from a transmi

Digital hydraulic well control system

Digital signal receiver for measurement while drilling...

Direct switching modulation for electromagnetic borehole telemet

Directional signal and noise sensors for borehole...

Disposable electromagnetic signal repeater

Disposable electromagnetic signal repeater