Loggerhead DSG-ST User manual

1"
"
"
"
"
DSG-ST Ocean Acoustic Recorder
"
"
"
www.loggerhead.com"
Updated"30"March"2017"

2"
"
Part I: Initial Setup
IMPORTANT: Install software drivers BEFORE connecting to
USB.
1. Download and install Soundtrap Host software from www.loggerhead.com DSG-ST
page.
2. Launch Sound Trap Host Software
3. Remove recorder from housing and ensure that it is powered by 3 D-cell
batteries in at least one bay
4. Use provided micro USB cable to connect the recorder to your computer
"
" "

3"
"
5) The drivers will take a few minutes to install. Once complete the recorder will
appear in the left hand window under “Device List.”
NOTE: Occasionally it will require several moments for the computer to
recognize the board. It also may take a more than one insertion of the
USB plug before it recognizes the board. If this continues to be an
issue follow the steps included at the end for reset- ting the USB hub in
Windows 7.
" "
6) Select the device by clicking on its label under “Device List”.
" "

4"
"
Part II. Setting up a Recording Deployment
Recording State
From this section you select how the recorder will start: either when disconnected from
the USB or via the remote control. There is no salt water or depth detection for the
DSG-ST Ocean.
Recording Schedule
Record Continuously: Will record continuously when box checked. If not checked, the
record interval settings will be used.
Audio Options
Sampling Mode: Only Wave mode is enabled.
Sample Rate (kHz): Select one of the sample rates. You can record sound frequencies
up to half of the sample rate.
X3: Check to enable lossless data compression. This is a good idea for deployments
that will use a lot of memory.
Gain:

5"
"
Low: 21 dB gain (~180 dB re 1uPa clip level)
High: 33 dB gain (~168 dB re 1uPa clip level)
High setting is recommended setting unless you will be in a loud environment.
The hydrophone shipped with the DSG-ST has a typical sensitivity of -201 dBV/uPa.
Deploy
When done with settings click the ‘Deploy” button at the bottom of the screen.
Remove microUSB cable.

6"
"
Part III. Starting Recording
1) Fill battery bays with 3 new D-Cell Batteries.
Each battery bay will provide power for about 20 days of continuous recording
time.
There is an Excel deployment time calculator that can be downloaded from the
loggerhead.com DSG-ST page to estimate deployment duration based on duty
cycled recordings.
Tape batteries in place.
2) Aim the remote at the recorder boards and press
the “Start” button.
A faint red and green light will flash settling to an
intermittently blinking green light.
There is an indicator red LED in the hydrophone that
will illuminate during recording. The red hydrophone
LED will go out when the recorder is sleeping.
Note: One remote can trigger multiple instruments if
they are within the range of the remote.
3) Lightly grease o-rings and seal housing for deployment.

7"
"
Part IV. Data Download
DATA CAN ONLY BE DOWNLOADED
FROM THE DSG-ST BOARD.
DO NOT INSERT CARD INTO PC.
1) Remove DSG from Housing.
2) Aim the remote at the recorder boards and press
the “Stop” button.
3) Connect the DSG-ST board to the PC with the
microUSB cable.
4) Once selected, the recorder will open to the
“Retrieve” tab and download the recording directory.
Select the recording(s) that you wish to download and
click, “Download”.
Clicking “Open Save Folder” button will show where
the individual recording folders are saved on your
computer. These will include metadata files and a
.wav file that can be used in the audio processing
software of your choice.

8"
"
5) When files are downloaded, the card can be wiped by clicking “Delete All.”
The entire card is deleted, so this operation may take a few minutes for a large card.

9"
"
Calibration
There are two aspects to calibration: the hydrophone and the DSG-ST gain. The
system gain is calculated as Recorder Gain + Hydrophone Sensitivity.
Typical hydrophone sensitivities are -201 dBV/uPa.
The hydrophone is supplied by HTI and a calibration sheet for each hydrophone is
included with the recorder.
The recorder has two gain settings:
Low: 21 dB gain (~180 dB re 1uPa clip level)
High: 33 dB gain (~168 dB re 1uPa clip level)
Internal Calibration Signal
Each recording starts by playing internal electrical calibration tones.
These signals are 300 uV RMS in amplitude, and can be used to monitor the electrical
calibration of the recorder.

10"
"
Troubleshooting USB
If the DSG is not being recognized by the sound trap software try the following:
1) Press STOP on the remote control while the recorder is connected.
2) Restarting your computer to reset the USB port.
3) Contact Loggerhead

11"
"
Sealing Housing
Pay special attention to make sure the o-ring in the top of the lid stays in place
and does not fall down when screwing the lid on.
The housing lid should be hand-tightened.
DO NOT USE THE STRAP WRENCH TO CLOSE THE LID!
Vent Plug
Some versions of the DSG-ST have a vent
plug.
This plug is only to be used if there is a
leak in the housing.
A leak in the housing can be dangerous because the housing will pressurize internally
to the same pressure as the depth of deployment.
If there is a leak, it is critical to relieve the pressure before removing the lid, otherwise
the lid could fly off.
The vent plug can be used to relieve the pressure, by turning it slowly until you start
hearing air come out. Once air starts coming out, stop unscrewing and wait until air
stops coming out. The vent plug is designed to stay in the endcap and safely vent air
through holes machined in the plug.
Once the internal pressure has equalized, you may remove the top lid with the
hydrophone. There is no need to fully remove the vent plug. Then gently retighten the
vent plug. On PVC housings be very careful not to overtighten the plug, otherwise
the threads in the bottom endcap may strip.

12"
"
Documentation Revision History
26 October 2016 v2.1. Added section on vent plug
7 March 2017 v2.2 Corrected calibration signal voltage from 30 uV rms to 300 uV rms
30 March 2017 v2.3 Added information on hand-tightening housing