The agenda for Wednesday was to prepare the underwater instruments for deployment and then load up the boat and return to the station. After installing the underwater instruments, we could then conduct an informal "reef check" exercise to be led by Pamela in the vicinity of the station. We had decided not to follow strict reef check protocols because of the unsuitable topology of the ocean floor in that area (on this trip we were both limited to a maximum depth of 30 feet), but rather to "rehearse" reef check methods for future use and at the same time to collect some notes about the biological environment of the station. There was no plan to do any pylon climbing on this day, instead we would return to the lab after diving so that I could reprogram/rewire the instruments so that we would be ready for Thursday's reinstallation and activation of the station.
Prepping the instruments mostly involved installing the batteries in the SeaBird CTDs and connecting to them to set their dates and times and verify that they were working. We had planned to leave the dock by 9:30am but unfortunately the CTDs would not respond to any communication efforts, either one of them, and by 10am I decided to cancel the day's boat work and diving to devote myself to the electronics entirely.
By noon I had consulted with SeaBird technical support and what AOML personnel could be reached, and I was still unsuccessful in communicating with the CTDs. [Note: tech support's first instruction to me was to connect to the SeaBird CTDs with their own SeaBird communications cable, which to my knowledge we do not have. If we continue to deploy these SeaBird CTDs we should definitely acquire and travel with one of these cables for use in debugging problems like these.]
I then turned to the other electronics work: downloading the station's local memory files, uploading the new datalogger program, reprogramming the serial port units (SIO4s), replacing the four aerial instruments on their three masts (the anemometer and electronic compass share the same mast), replacing old cables, and testing all plugs to ensure that their wire/pin connections were unbroken. I also cut away the duct tape from the old battery packs and taped up the new batteries with spectra-line handles in the same way.
During this work, one of the "brain" fuses was discovered to have blown, and was replaced. It's not clear when this happened.
While working away in the lab I managed to meet up with Wess Merten, who has been doing the monthly station cleanings for several years, and asked him for three things: one, the "groundtruth" CT sensor which I needed to connect on Thursday to ensure that its cable and wiring were properly connected; two, the deep light sensor that had been removed in July of 2011; and three, the shallow CTD that had been removed in March of 2012. He was able to locate the first two sensors immediately but he did not know the exact whereabouts of the CTD and said that he would look for it.
By the end of the day everything was ready for deployment but the CTDs were still non-operational. I wondered if my new laptop's USB-to-Serial adapter was somehow failing to communicate with the instruments, although it worked fine with the light sensors and the datalogger. [Also, I connected to the shallow light sensor that we'd retrieved the day before and it still appeared to be operational.] There was no good explanation for why (1) both CTDs were unable to communicate when (2) they had both been operating normally during testing in my office last January. I decided we could try deploying them anyhow, reasoning that if the USB-to-Serial adapter was somehow to blame then perhaps the direct connection to our datalogger would work as it had in January. In the worst case, if neither CTD would work, we could permanently install the "groundtruth" CT until such time as replacement CTDs could be installed.