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- Overall the bathy was working and we were able to ping the seafloor during transits and as we arrived on site for PDRs. Still intermittent issues with signal dropping out when using the 3.5kHz at powers above -12dB. I'm not sure if this is related to the recent issues or just something that our system does now.
- The connections to the LPT that were loose in underway were checked but seem fine. Also during one of lost signal events I was able to go down and listen for the ping from lower 'tween accommodations and it sounded like it was pinging at an appropriate level.
- Coming on to site U1561 the 12kHz had to be used for the PDR as the 3.5kHz channel was not picking up any return signal.
- The best(most consistent) settings found during this expedition were -12dB for power and between 24-33dB for gain. Both of the sites were in waters approaching 5000m depth and most of the transit depths were between 3500-5500m with relatively calm waters. Gain of 15 dB was used between the Azores and Iceland EEZ on the 3.5 kHz with great results. The water depths on this leg of the transit were much shallower.
Magnetometer
- No issues with the towfish itself during any of the deployments.
- One issue to note was the SeaSpy software losing GPS sync with the towfish so that the measurements were not being tagged with GPS data. I have not seen this issue before and am not sure of anyway to combat it. It seemed to happen at 00:00 when looking back at the files. So it may have something to do with the PC Time sync throwing an error and resetting the sync with towfish. Luckily to reset you can simply stop cycling and logging and re-sync the towfish before starting to cycle and log again without having to reel it in and re-deploy.
- The level-wind was still having issues with movement when we first started to deploy the towfish. It seemed to work well when using the manual push buttons to control the movement. However if you were not careful it would move too much to either side and become jammed at the end of travel. When this happens the cover must be removed from the gear works and the main gear has to be turned manually with a wrench until the level-wind is free enough that the motor will drive it again. Adjustments were made to each of the limit switch mechanisms to fix this and it has not happened since.
- The starboard side limit switch was simply no triggering soon enough to stop the level-wind from reaching end of travel because the level-wind is slightly offset from the winch drum. By unscrewing the metal rod that triggers the sensor about an inch this issue was resolved. The problem with the way the level-wind is aligned with the winch drum is that this means it now harder to get the cable all the way to the edge of the drum. I think not getting the motor jammed and losing time having to hand crank it loose is worth losing an inch of usable drum space.
- The port side limit sensor was found to not be working at all and could not be triggered no matter what. Upon disassembly it was discovered that the sensor was installed in the wrong orientation(pictured below). This may have been faulty QC/QA coming directly from the manufacturer. When re-installed with the sensor facing up the limit switch would engage the motor properly before it could become stuck.
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- Updated WinFrog user guide to include new Trimble SPS356 info including log in credentials to reach the browser set-up.
- Added troubleshooting section to Bathy2010 user guide to include re-installation solution for Bathy2010 software.