3 Jan 1974
- waterbody:North Atlantic OceanGrand Turk Island; U.S. Naval Facility
NOTES: Notes from tape: "Time 1900 Zulu 3Jan1974." Notes from analysis log: "Cassette number side down - rewind. Ambient noise moderate, distant ship taffic heard, and increases heavily around 280. Humpback: Neg.; Minke: Pos.; No. Heard: 2; No. Trains: 9; Need for further analysis: Yes - check 708, good level, long. Notes: at 010 hear thump train, low level at 129 thump train. At 180 weak thump train, at 334 a mod level thump train, 468 weak thump train; at 546 strong thump train, at 626 a weak train, again at 708 a loud strong one, at 725, pieces of 2nd source?"
[Notes from analysis log for all tapes in the GRANDTURKS series: "Six half-hour background recording samples on selected days for a period of 53 days... to detect the arrival and departure of the Humpback whales (via sounds) for the season in the Caribbean Sea, Mouchier, Navidad and Silver Banks...There are indications that recordings used a 420Hz Low Pass Filter. Recording equipment used was a Realistic model CTR-19. Cassette recorder operating on 110VAC, Freq 60-10,000Ha.. The Realistic recorder is poor recording frequencies below 60Hz as evidenced by spec sheet and sonograms. There is 120 & 180Hz electrical interference 'splatter' on some tapes. In certain cases when the ambient is low, the gain of the systems are raised hence we have heavy interference masking wanted signals. This could be caused by a fluorescent light fixture near the recording system? I doubt that it is in the hydrophone pre-amp network." See analysis log for more details.] SEAOCEAN