A method of receiving signals in a spread-spectrum telecommunications system with terrestrial repeaters, and a terminal for receiving, the terminal including two rake receivers, each receiver having a set of demodulation channels and a combiner. An exemplary surgical drilling device in accordance with the present invention comprises a housing, a retractable guide tube assembly, and a flexible cable drill. The imaging array sensor is operable to capture image data, and the control processes the captured image data. Otherwise, if an unlock button activation is detected, the counter is reset to zero. The static sliding window synchronizes the command sequence to the response by the slave device and adjusts for the timing semantics of the acknowledgment signal of the slave device.