11/19/2014 — admin
The EM302 and EM710 multibeams were successfully calibrated and verified for use with both the loaner Seapath MRU and the new POS MV. Angular offsets were small except for the roll bias for both the EM710 and EM302. As both multibeam systems have the same large roll bias, it is likely the result of a shift in the mounting angle of the MRU. Both SIS acquisition systems have been updated with the new calibration results.
The transducer impedances are similar to baseline measurements in 2012 and with those taken in 2013 and during the spring 2014 test. Transducer conditions, based on these tests, are acceptable and there is no sign of degradation of the transducer arrays.
Noise levels for the EM710 remain unchanged and very low. Noise levels for the EM302 have returned to their lower levels at speeds below 8 know. More testing is necessary to see if any noise issues remain at higher speeds.
As a whole, the two multibeam systems are in satisfactory working condition and should be good for mapping for the upcoming field season.