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Ship contact info


VHF Radio Call Sign:
WDE4414
Iridium phone cockpit:
00 - 88 1677 72 7018
Iridium spare 1:
00 - 88 1621 41 8079
Iridium spare 2:
00 - 88 1621 44 3804
Emergency Beacon:
ID: ADE90 05931 C34D
Handheld Emergency Beacon:
ID: LC 4652
Hovercraft registered in Delaware, US:
DL 1519 AB

Maintenance


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Last update: June 26, 2020, at 08:55 PM
Version: pmwiki-2.3.22


    HOVERCRAFT "SABVABAA"    

     SEISMIC PROFILING

UNIVERSITY OF BERGEN
Department of Earth Science
 Allé gt. 41, N-5007 Bergen, Norway 
             
0.1 DRAFT - 14 July, 2022 OM OM -
VER. STATUS CHANGE DATE BY CKD APPD
Click to enlarge.

A 20 inch3 Bolt airgun. Click to enlarge.

Click to enlarge.

Air bubbles from a shot. Click to enlarge.

SURVEY 2022


Instrumentation diagram


Drawing No. HC-001-E-G-001-1, Rev-A. Click to open PDF version.

RTM3 Trigger interface


Chassis connector, RTM3
  • 26-pin F
  • Model: Souriau 851-07A16-26S50-A7

Internal wiring, RTM3 trigger connector. Source: RTM3 manual.

Matching cable connector:
  • 26-pin M
  • Model: Souriau 851-06EC16-26P50
  • Supplier: RS, stock no: 687-6673: "Souriau, 851 26 Way Cable Mount MIL Spec Circular Connector Plug, Pin Contacts,Shell Size 16, Bayonet Coupling"

From RTM3 manual, section 12.1 "Breakout Box Diagram"

Click to enlarge.

From RTM3 manual: RTM3 time stamp trigger input -- G = center coax; R = coax shield. Click to enlarge.

Backup: Installing all software on Win 11 laptop


In order to prepare for future replacement of main seismic computer -- a 2008 vintage Dell Latitude D630 laptop running WinXP -- we attempted to install all software on a modern laptop.

New laptop: Dell Latitude 7420


  • Laptop: Dell Latitude 7420
    • Power input: USB-C
    • Ethernet port: No (only WLAN). GEODE program requires Ethernet port for communication with the GEODE seismograph, so a solution must be found.
    • USB-A port: 1 ea
    • USB-C port: 1 ea
    • HDMI port: Yes
  • OS: WIN11

Adapters used


  • 4-port RS232 hub, from USB-A
  • 4-port USB-A hub, from USB-C
    • Plexgear Portable 420 USB 3.0-hub 4-way
    • Supplier: Kjell & Co, P/N: 69515
  • Ethernet adapter, from USB-A
    • LevelOne, mod USB-0301 (H/W Ver: 1.0)
    • Supplier:

Installing Python interpreter and three libraries


PYTHON INTERPRETER:

EXTERNAL LIBRARIES REQUIRED:

Install three libraries:

First open terminal window, then use these commands (assuming Python interpreter was installed in default directory, c:\Python27\):

 cd c:\Python27 .\python -m pip install -U pip
 .\python -m pip install pyserial==2.7
 .\python -m pip install psutil

Installing GEODE software


Install GNSS/Survey logger, and Mini-GUNCO software, in two new directories


In terminal window:

 cd c: mkdir HOVERCRAFT_GPS_2022
 mkdir HOVERCRAFT_GUNCO_2022

Download:

  • gunco-ver4-2022-07-13.py to HOVERCRAFT_GUNCO_2022
  • gunco.ini to HOVERCRAFT_GUNCO_2022
  • hovercraft-GNSS-ver3-2020-07-13.py to HOVERCRAFT_GPS_2022

Run the programs, in separate terminal windows:

Terminal window #1:

 cd c:\HOVERCRAFT_GPS_2022
 c:\python27\python .\hovercraft-GNSS-ver3-2020-07-13.py

Terminal window #2:

 cd c:\HOVERCRAFT_GUNCO_2022
 c:\python27\python .\gunco-ver4-2022-07-13.py

Screenshot


Click to enlarge.

13 July, 2022: Three programs operating on WIN11 laptop:
            (a) GNSS Distributor/Survey logger;
            (b) Mini-GUNCO program;
            (c) GEODE program.
Red arrow marks how Mini-Gunco program exports serial RS232 Shotpoint event data, which are captured by GEODE program (using separate COM-port). The event data string looks like NMEA telegram, starting with "$PUIBNAV", where means P="Proprietary", UIB="Universitetet i Bergen", and NAV="Navigation data". Click to enlarge.

SURVEY 2020


Laptops, 2x


GNSS units


Navilock NL-8004U USB 2.0 GNSS Receiver

Time stamping of airgun firing


  • Remote Trigger Module 3, or RTM3, made by Seismic Source Company
  • Ethernet: The RTM3 has a fixed IP and not a DHCP server. If the RTM has a serial number of 171 the IP address will be, 10.0.1.71. The computer should be set to 10.0.0.101. This link shows a video on setting up the computer IP address: https://www.youtube.com/channel/UCWszOSFMYMt20E-d2CD4xvQ
  • Display: The "1" is the GPS indicator value from the NMEA string, $GPGGA, that is being received by the RTM3 and sent by the GPS receiver. The "P" means that the RTM3 is receiving the PPS from the GPS receiver. The "T:OK" means the RTM3 is time synchronized with the GPS receiver’s NMEA messages and PPS.

Under consideration: https://verif-i.com/product/gps-sync/

GEODE seismic recorder


Hardware


  • Trigger Interface cable: Item: 0026960-10 "CBL ASSY, TRIGGER (BNC TO 3-PIN) CO: SN030437

Software


USB to serial adapters


  • 1-port serial
  • Manufacturer: ST Labs

SURVEYS 2008 - 2019


Single hydrophone


We have been using:

Splicing of hydrophone cable


Hydrophones are normally ordered unterminated. In order to splice the hydrophone cable to a suitable underwater pigtail cable (which is delivered with one connector; the other side is open) an inline cable splicing kit must be used:

Norwegian suppliers:

Interface between hydrophone AQ-18 / 6 ch streamer and GEODE recording system


Click to see large version:

Interface between Teledyne AQ-18 Hydrophone  / 6 channel mini-streamer and Geode Recording system (click to see large version)
Interface between Teledyne AQ-18 Hydrophone / 6 channel mini-streamer and Geode Recording system - click to see large version.
Recommended AQ-18 decoupling and wiring.

Recommended AQ-18 decoupling and wiring.

The recommended decoupling is done in the interface box shown below. The interface is also furnished with a DC/DC-converter in order to provide a clean 12 Vdc power source for the hydrophone.

Teledyne hydrophone AQ-18 interface box - click to enlarge.
Teledyne hydrophone AQ-18 interface box (click to enlarge).
6 channel mini-streamer terminals, Geode recording cable (click to enlarge).
6 channel mini-streamer terminals, Geode recording cable (click to enlarge).

Mini-streamer, 6 channels


Mini-streamer lay-out

Mini-streamer layout.

  • Mfr: SigFrance
  • Channels: 6
  • Model: SIG 16.6x4.46
  • S/N: 08044
  • Date: 04/2008
  • Hydrophone elements:
    • Sensitivity: -90 dB re 1 V/uBar, +/- 1 dB
    • Frequency response: Flat +/- 1 dB over the frequency range 10 to 1000 Hz
    • Max operating depth: 80 m
    • Capacitance: 18.0 +/- 1.0 nF @ 20 deg C and 1 kHz
  • Active section:
    • Length: 46 m
    • Diameter: Inside Ø=25 mm, outside Ø=30.5 mm
    • Density: 1.05
    • Oil: 880
    • Number of channels: 6
    • Number of hydrophones per channel: 4
  • Leadin cable:
    • Length: 75 m
    • Breaking strength: 500 Kg
  • Preamplifier:
    • Number of channels: 6
    • Gain: 32 dB (=40x)
    • Bandwidth: 2 - 3000 Hz
    • Maximum voltage output: 12 V p-p
    • Current consumption: < 2 mA

Seismic source


Recording


Geometrics Geode


GPS for time- and position stamping of data


  • GPS: Garmin GPS 35-HVS
    GPS has been configured to only output GPGGA NMEA telegram. Link to configuration program and User Manual. The GEODE has a small quirk in that you cannot specify the NMEA telegram to record alongside seismic data. So to ensure consistency in time/positional logging the attached GPS should output only one type of NMEA telegram.

Configuration for use with UBS based GPS


If a USB based GPS should be used, there is a problem as the Geode software only accepts serial port in the Keep('COM1') to Keep('COM4') range, see screenshot below.

The USB based GPS will normally be assigned to a COM number in a higher range. So a remapping of COM port assignment need to be done.

Geode software serial setup menu
Geode software serial setup menu.

Default COM port assignment and NMEA telegram output from ordinary USB/GPS shown below.

Data from USB/GPS, default selection of telegrams.
Data from USB/GPS, default selection of telegrams.

Re-assigning COM port to fall within the 1-4 range is accomplished from Control Panel -> Hardware -> Comport -> (properties of USB/GPS port)

In advanced settings, you can force comport setting to an available number within the 1-4 range that Geode software accepts.

Backup recording system


Ref. notes on this page.

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Page last modified on July 29, 2022, at 09:05 AM
Department of Earth Science
University of Bergen
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