<div dir="ltr">Ian, welcome back!!! Your theory of increased currents makes sense to me. Hank, I would suggest the following experiment next time out. Get the sub rotating at depth. Then kill all power and watch the compass while the sub's momentum keeps her turning. <div><br></div><div>Best,</div><div><br>Alec</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Jun 27, 2016 at 10:35 PM, irox via Personal_Submersibles <span dir="ltr"><<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div style="font-size:13px;color:rgb(0,0,0);font-family:arial,sans-serif">Hi Hank,<br><br>another possibility is that something on your sub is generating a strong magnetic field, which only occurs at depth. An example could some motor which is drawing more current (and creating a bigger magnetic field), possibly due to pressure around a shaft seal.<br><br>Or could it be time related? As in a electrostatic charge or something building up over time, not interfering with the compass at the start of the dive in shallow water, but building up and creating problems once at depth.<br><br>I'm hoping to use a fiberoptic gyro to aid underwater navigation. Possibly in conjunction with a 3D magnetometer/flux-gate-compass.<br><br>Cheers,<br> Ian.<br>(I was finally able to subscribe to the mailing list again. But I have been following archive for the last few years.)<br><br><blockquote style="padding-left:5px;margin-left:0px;border-left:#0000ff 2px solid;font-weight:normal;font-style:normal;text-decoration:none;font-size:10pt;font-family:arial,sans-serif;color:black"><span class="">-----Original Message-----
<br>From: hank pronk via Personal_Submersibles <u></u>
<br></span><span class="">Sent: Jun 27, 2016 2:06 PM
<br>To: Personal Submersibles General Discussion <u></u>
<br></span><div><div class="h5">Subject: Re: [PSUBS-MAILIST] gyro compass
<br><br><u></u><u></u><u></u><u></u><div style="color:#000;background-color:#fff;font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px"><div><span>Its Aliens, Alan,</span></div><div dir="ltr"><span>I tried it inside the sub and it tries to work but is totally off. I did squeeze it with the body off to simulate depth and it worked fine in the shop being squeezed. </span></div><div dir="ltr"><span>Hank</span></div> <div><br><br></div><div style="display:block"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div dir="ltr"><font face="Arial" size="2"> On Monday, June 27, 2016 2:39 PM, Alan James via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br></font></div> <br><br> <div><div><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"><div><span>Hank,</span></div><div><span>I think your theory about the UFO is looking good at this stage.</span></div><div><span>It didn't work at 10ft, that's about 5psi; So have you tried squeezing</span></div><div dir="ltr"><span>it in various places to replicate that? Or what about mounting it</span></div><div dir="ltr"><span>inside the hull on a pole in the center of the dome area, as far</span></div><div dir="ltr"><span>as possible from the hull. If it worked it would eliminate any Alien</span></div><div dir="ltr"><span>influences & indicate that the water pressure was the problem.</span></div><div>Alan<br clear="none"><br clear="none"></div><div style="display:block"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div><div dir="ltr"> <font face="Arial" size="2"> </font><hr size="1"> <b><span style="font-weight:bold">From:</span></b> hank pronk via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none"> <b><span style="font-weight:bold">To:</span></b> Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> <br clear="none"> <b><span style="font-weight:bold">Sent:</span></b> Monday, June 27, 2016 11:26 PM<br clear="none"> <b><span style="font-weight:bold">Subject:</span></b> Re: [PSUBS-MAILIST] gyro compass<br clear="none"> </div> <div><br clear="none"><div><div><div style="color:rgb(0,0,0);font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px;background-color:rgb(255,255,255)"><div><span>Alan,</span></div><div dir="ltr"><span>I took my compass apart and it is perfect, it works perfect in my shop etc. I put it in the lake and it is stuck on N most of the time. </span>Occasionally it will move. I think there is some mineral interference or an old sunken UFO messing with it. </div><div dir="ltr">Hank</div> <div><br clear="none"><br clear="none"></div><div style="display:block"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div><div dir="ltr"><font face="Arial" size="2"> On Monday, June 27, 2016 5:11 AM, Alan James via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br clear="none"></font></div> <br clear="none"><br clear="none"> <div><div><div><div style="color:rgb(0,0,0);font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px;background-color:rgb(255,255,255)"><div><span>Hank, </span></div><div dir="ltr"><span>why would you want a turn & bank indicator above some sought of compass?</span></div><div dir="ltr"><span>There are a multitude of inexpensive underwater compasses that scuba divers use,</span></div><div dir="ltr"><span>although they may be a bit small to be read at a distance. Possibly there is some</span></div><div dir="ltr"><span>issue with the compression of the oil stopping your compass from functioning?</span></div><div dir="ltr"><span>Mounting the compass outside the hull seems to be standard practice & I haven't</span></div><div dir="ltr"><span>heard of any failing. Perhaps someone with previous issues with them could comment.</span></div><div dir="ltr"><span>Alan</span></div><div dir="ltr"><span> </span></div><div><br clear="none"><br clear="none"></div><div style="display:block"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div><div dir="ltr"> <font face="Arial" size="2"> </font><hr size="1"> <b><span style="font-weight:bold">From:</span></b> hank pronk via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none"> <b><span style="font-weight:bold">To:</span></b> Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> <br clear="none"> <b><span style="font-weight:bold">Sent:</span></b> Monday, June 27, 2016 10:37 PM<br clear="none"> <b><span style="font-weight:bold">Subject:</span></b> Re: [PSUBS-MAILIST] gyro compass<br clear="none"> </div> <div><br clear="none"><div><div><div style="color:rgb(0,0,0);font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px;background-color:rgb(255,255,255)"><div><span>Kieth,</span></div><div dir="ltr"><span>I stand corrected, a turn and bank indicator is just the ticket and tons of them on </span>eBay for cheap. I was focusing on compass only, but these indicators are much cheaper and more available. </div><div dir="ltr">Thanks' for the tip</div><div dir="ltr">Hank</div> <div><br clear="none"><br clear="none"></div><div style="display:block"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div><div dir="ltr"><font face="Arial" size="2"> On Sunday, June 26, 2016 6:25 PM, hank pronk via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br clear="none"></font></div> <br clear="none"><br clear="none"> <div><div><div><div style="color:rgb(0,0,0);font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px;background-color:rgb(255,255,255)"><div><span>Hi Kieth,</span></div><div><span>My understanding is the aircraft units are noisy, I assume that is the air units. They are hard to find in guaranteed working condition for a price that works for me. If you know of any for a descent price-please let me know.</span></div><div><span>Hank</span></div> <div><br clear="none"><br clear="none"></div><div style="display:block"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div><div dir="ltr"><font face="Arial" size="2"> On Sunday, June 26, 2016 6:16 PM, k6fee via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br clear="none"></font></div> <br clear="none"><br clear="none"> <div><div><div><div>Hank, </div><div><br clear="none"></div><div>Try using a gyro compass ( or atifical horizon) from an aircraft. They sre either air, vaccum or electric powered.</div><div><br clear="none"></div><div>Keith </div><div><br clear="none"></div><div><br clear="none"></div><div><br clear="none"></div><div><div style="color:rgb(87,87,87);font-size:85%">Sent from my Verizon, Samsung Galaxy smartphone</div></div><div><br clear="none"></div><div><div style="color:rgb(0,0,0);font-size:100%"><div>-------- Original message --------</div><div>From: hank pronk via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> </div><div>Date: 6/26/16 4:11 PM (GMT-08:00) </div><div>To: Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> </div><div>Subject: [PSUBS-MAILIST] gyro compass </div><div><br clear="none"></div></div><div style="color:rgb(0,0,0);font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:12px;background-color:rgb(255,255,255)"><div dir="ltr">I am going to try to make a gyro compass, looks doable. I don't care about what direction I am going-I just want to go in a strait line. I will point the sub in the direction I want to go at the surface, then turn on the gyro and sink. Then I can just follow the gyro.</div><div>Hank</div></div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" href="mailto:Personal_Submersibles@psubs.org" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" href="mailto:Personal_Submersibles@psubs.org" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" href="mailto:Personal_Submersibles@psubs.org" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" href="mailto:Personal_Submersibles@psubs.org" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" href="mailto:Personal_Submersibles@psubs.org" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div><br><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" href="mailto:Personal_Submersibles@psubs.org" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br><br></div> </div> </div> </div></div><u></u><u></u><u></u><u></u></div></div></blockquote></div></div>
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