High precision azimuth can be provided rapidly by the north finder based on rate biased RLG, which plays an important role in military and civil applications. The Error characteristic of rate biased RLG, is theoretically studied, same to the factors which influence the precision of north finder. Experimental research is carried out to work parameters and functions of the north finer, which is an experimental machine. The data provided by experiments is used on the next step of engineering. Main researches a...