<div dir="ltr"><div dir="ltr"><div dir="ltr">Alan,<div><br></div><div>Yes, I deal with geolocation and tracking problems for work. Mostly this is on the land or in the air, but my personal interests carry into the water. </div><div><br></div><div>The problem that you face is how to provide multiple reference paths to the GPS receiver. DSP-Comm simplifies the problem by only transmitting the range to the base station (deck unit). If you want a better solution you would implement something similar to a LORAN-C network. More simply you could have a modem on your deck that receives in two different frequency bands so you can perform attenuation ranging on different frequencies for improved accuracy and then triangulate the location of you underwater asset (the longer the baseline the better - a hydrophone off the bow and stern). If you want you could still have a transmit hydrophone like DSP-Comm supplies for full duplex communications that also transmits current location to the sub.</div><div><br></div><div>Regards,</div><div>James</div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Jan 16, 2020 at 6:25 PM Alan via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="auto"><div></div><div>Thanks for the insight into their product James.</div><div>One of the problems is getting the GPS signal down to the sub, &</div><div>I have been looking at this company .....</div><div><a href="https://dspcommgen2.com/aquatrans-underwater-acoustic-dunking-hydrophone-transducer/" target="_blank">https://dspcommgen2.com/aquatrans-underwater-acoustic-dunking-hydrophone-transducer/</a></div><div>for data transfer transducers & modems. </div><div>They are reasonably inexpensive & are based in Bangkok.</div><div>BTW you seem to know your stuff, are you involved professionally in that area</div><div>or is it just an interest? </div><div>Regards Alan </div><div><br></div><div><br></div><div><br>On 16/01/2020, at 8:54 PM, J. Foulkes via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr"><div dir="ltr"> Hello everyone,<br><br><div>OEngineering was at CES this year with this product and I had several lengthy discussions with them about their system. So, first I would like to point out that the real focus of this system is for citizen science applications (inexpensive) not for extended dive precision mapping. If this is your application, you would be much better served using a control laptop with external IMU and GNSS devices as the IMU on this product doesn't have the best freerunning accuracy. Secondly, it seemed that what they were really pushing as the technology you are paying for is the app interface. It was unclear from talking with them what interface would be available (API) for downloading raw data on points of interest and continuous tracking outside of this interface. Also, one thing to note is that if you were using this in your sub for datalogging (it requires manual button pressing for POI logging) you would need a GNSS repeater with a bulkhead pass through.</div><div><br></div><div>Regards,</div><div>James Foulkes</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Jan 15, 2020 at 11:22 PM T Novak via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div lang="EN-CA"><div><p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">This does look interesting, Brian.<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Worth thinking about.<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)">Tim<u></u><u></u></span></p><p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(31,73,125)"><u></u> <u></u></span></p><div><div style="border-right:none;border-bottom:none;border-left:none;border-top:1pt solid rgb(225,225,225);padding:3pt 0in 0in"><p class="MsoNormal"><b><span lang="EN-US" style="font-size:11pt;font-family:Calibri,sans-serif">From:</span></b><span lang="EN-US" style="font-size:11pt;font-family:Calibri,sans-serif"> Personal_Submersibles [mailto:<a href="mailto:personal_submersibles-bounces@psubs.org" target="_blank">personal_submersibles-bounces@psubs.org</a>] <b>On Behalf Of </b>Alan via Personal_Submersibles<br><b>Sent:</b> Wednesday, January 15, 2020 4:38 PM<br><b>To:</b> Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br><b>Subject:</b> Re: [PSUBS-MAILIST] 3D dive recording, kickstarter<u></u><u></u></span></p></div></div><p class="MsoNormal"><u></u> <u></u></p><div><p class="MsoNormal">Looks useful Brian.<u></u><u></u></p></div><div><p class="MsoNormal">Some sort of mapping is definitely useful.<u></u><u></u></p></div><div><p class="MsoNormal">I have just been looking at GPS receivers to see how they can be water / pressure<u></u><u></u></p></div><div><p class="MsoNormal">proofed. I think a GPS system would be the bare minimum. <u></u><u></u></p></div><div><p class="MsoNormal">If you found a treasure chest you could at least head straight to the surface<u></u><u></u></p></div><div><p class="MsoNormal">& get a GPS coordinate.<u></u><u></u></p></div><div><p class="MsoNormal">Alan<u></u><u></u></p></div><div><p class="MsoNormal" style="margin-bottom:12pt"><br>On 16/01/2020, at 11:26 AM, Brian Hughes via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<u></u><u></u></p></div><blockquote style="margin-top:5pt;margin-bottom:5pt"><div><p class="MsoNormal" style="background:white"><span style="color:rgb(33,33,33)">OK,<u></u><u></u></span></p><p class="MsoNormal" style="background:white"><span style="color:rgb(33,33,33)"><u></u> <u></u></span></p><p class="MsoNormal" style="background:white"><span style="color:rgb(33,33,33)">This looks interesting:<u></u><u></u></span></p><p class="MsoNormal" style="background:white"><span style="color:rgb(33,33,33)"><u></u> <u></u></span></p><p class="MsoNormal" style="background:white"><span style="color:rgb(33,33,33)"><a href="https://newatlas.com/outdoors/brizo-3d-scuba-dive-maps/?fbclid=IwAR0bwSGSy8zlABzonbS9PO4M-hyca94ADtn57E7YlccucUaqQGz3WNFqYBQ" target="_blank">https://newatlas.com/outdoors/brizo-3d-scuba-dive-maps/?fbclid=IwAR0bwSGSy8zlABzonbS9PO4M-hyca94ADtn57E7YlccucUaqQGz3WNFqYBQ</a><u></u><u></u></span></p><p class="MsoNormal" style="background:white"><span style="color:rgb(33,33,33)"><u></u> <u></u></span></p><p class="MsoNormal" style="background:white"><span style="color:rgb(33,33,33)">Brian<u></u><u></u></span></p><div id="gmail-m_6885495292466673475gmail-m_5354910058707955157gmail-m_-7363731578596884931gmail-m_-4832939327670058524ms-outlook-mobile-signature"><div><p class="MsoNormal"><u></u> <u></u></p></div><p class="MsoNormal">Get <a href="https://aka.ms/ghei36" target="_blank">Outlook for Android</a><u></u><u></u></p></div></div></blockquote><blockquote style="margin-top:5pt;margin-bottom:5pt"><div><p class="MsoNormal">_______________________________________________<br>Personal_Submersibles mailing list<br><a href="mailto:Personal_Submersibles@psubs.org" target="_blank">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><u></u><u></u></p></div></blockquote></div></div>_______________________________________________<br>
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