Archive for April 28th, 2008

Port Angeles to Aleck Bay

Today we got an early start at 7:30 am due to small craft advisory warnings and strong winds reaching 30-35 knots. We weighed anchor and cooked breakfast as well as did our chores while under way. We planned to reach False Bay at the south end of San Juan Island by noon, taking into account the wind and wave advisories; we experienced calm, flat waters instead, with some scattered rain fall. To take advantage of this weather, we passed over Salmon Bank, a shallow area with interesting bathymetric profiles, to record bathymetry with the echoloctor. Shortly after, the group deployed the CRT hydrophone as well as the hydrophone array in order to practice properly getting them into the water as well as play with the gain settings. We took recordings from all four channels for a background noise exercise which we threw ourselves into after dinner. We got experience plugging files into one of Val’s programs designed to read RMS and convert it into dB. We also calculated signal to noise ratios for multiple sound files.

Read More