<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_1_1456986574653_3064"><span id="yui_3_16_0_1_1456986574653_3185">Wow some good products Steve,</span></div><div id="yui_3_16_0_1_1456986574653_3063" dir="ltr"><span>I had a look at your Ebay product inventory </span><a href="http://www.ebay.com/sch/tfmengineeringaust/m.html?_nkw=&_armrs=1&_ipg=&_from=" id="yui_3_16_0_1_1456986574653_3066">http://www.ebay.com/sch/tfmengineeringaust/m.html?_nkw=&_armrs=1&_ipg=&_from=</a></div><div class="qtdSeparateBR" id="yui_3_16_0_1_1456986574653_3062">I can see you will be a great source of knowledge for tracking down those tricky bits & pieces. </div><div class="qtdSeparateBR" id="yui_3_16_0_1_1456986574653_3062"> If Sean puts an LED between the pressure sensor & the solenoid valve or between the solenoid valve</div><div class="qtdSeparateBR" id="yui_3_16_0_1_1456986574653_3062" dir="ltr">& it's power source, he will be able to see which set of o-rings is not sealing. And if he was Cliff he would</div><div class="qtdSeparateBR" id="yui_3_16_0_1_1456986574653_3062" dir="ltr">be feeding the information to his PLC & displaying it on his HMI.</div><div class="qtdSeparateBR" id="yui_3_16_0_1_1456986574653_3062" dir="ltr">Cheers Alan</div><div class="qtdSeparateBR" id="yui_3_16_0_1_1456986574653_3062" dir="ltr"><br><br></div><div class="yahoo_quoted" id="yui_3_16_0_1_1456986574653_2897" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1456986574653_2896"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1456986574653_2895"> <div dir="ltr" id="yui_3_16_0_1_1456986574653_3003"> <font size="2" face="Arial" id="yui_3_16_0_1_1456986574653_3060"> <hr size="1" id="yui_3_16_0_1_1456986574653_3061"> <b><span style="font-weight:bold;">From:</span></b> Stephen Fordyce via Personal_Submersibles <personal_submersibles@psubs.org><br> <b><span style="font-weight: bold;">To:</span></b> Personal Submersibles General Discussion <personal_submersibles@psubs.org> <br> <b><span style="font-weight: bold;">Sent:</span></b> Thursday, March 3, 2016 7:22 PM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [PSUBS-MAILIST] Hatch interlock<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_1_1456986574653_2894"><br><div id="yiv9248003856"><div id="yui_3_16_0_1_1456986574653_3817"><div dir="ltr" id="yui_3_16_0_1_1456986574653_3877">Hi Sean,<br clear="none">
I really like the idea of vacuum monitoring for hatch leaking - nice one. Also Alan a good idea for a single central transmitter monitoring the whole thing.</div>
<div dir="ltr" id="yui_3_16_0_1_1456986574653_3820">A couple of thoughts from me:<br clear="none">
- as well as the vacuum breaker valves on the actual hatches, you'd need individual manual isolation valves in the 1atm chamber so you determine which was leaking, and in case one leaks.<br clear="none">
- You could protect the transducer from over pressure with a relief valve in the 1atm chamber (installed on the 1atm side of isolation valves)<br clear="none">
- I'm not sure how likely it really is, but if you got salt water into the vacuum space the water would quickly evaporate, leading the salt residue to accumulate over time<br clear="none">
- oil lubricated vacuum pumps, or at least the ones I've used, at only moderate vacuum can create smoke/oil vapour which would be uncomfortable in a sub. Using a diaphragm pump or similar you'd probably achieve a much poorer vacuum but no atmospheric contaminants<br clear="none">
- a vacuum switch would probably be cheaper and more likely to survive the over pressure, at the cost of less detailed info, ie. This one is good to 200m <br clear="none">
<a rel="nofollow" shape="rect" target="_blank" href="http://www.suco-tech.com/product.php?p=44&c=12">http://www.suco-tech.com/product.php?p=44&c=12</a><br clear="none">
- actually on reflection, I sell digital gauges for SCUBA gas mixing (shameless plug: <a rel="nofollow" shape="rect" target="_blank" href="http://m.ebay.com/itm/Electronic-Digital-Pressure-Gauge-for-SCUBA-Blending-Nitrox-Trimix-Oxygen-/262307605334?nav=SEARCH">http://m.ebay.com/itm/Electronic-Digital-Pressure-Gauge-for-SCUBA-Blending-Nitrox-Trimix-Oxygen-/262307605334?nav=SEARCH</a> ) and they are -1 to 400bar(g) in 0.1 bar increments, which would be ok for both the vacuum and over pressure, so it can't be too hard, and requires an ADC resolution of only 12 bits - if 10 levels of vacuum measurement would be ok?<br clear="none">
- I have some very reasonably priced transducer samples coming from the same supplier - if they work out ok I could send you one or at least the specs.<br clear="none">
- For a quick and easy way of turning high res analogue signals into useful digital data I can highly recommend this Arduino shield: <a rel="nofollow" shape="rect" target="_blank" href="http://rascalmicro.com/docs-precision-voltage-shield/">http://rascalmicro.com/docs-precision-voltage-shield/</a><br clear="none">
Brandon has made a couple of 18-bit versions for me, which are good enough for 0.1% readings from oxygen cells and the like. I've been meaning to order some more.</div>
<div dir="ltr" id="yui_3_16_0_1_1456986574653_3819">Well that turned into a bit of a ramble, hopefully some is useful.</div>
<div dir="ltr">Cheers,<br clear="none">
Steve</div>
<div class="yiv9248003856gmail_quote" id="yui_3_16_0_1_1456986574653_3816">On 3 Mar 2016 3:52 pm, "Sean T. Stevenson via Personal_Submersibles" <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none"><blockquote class="yiv9248003856gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;" id="yui_3_16_0_1_1456986574653_3815"><div class="yiv9248003856yqt6536156463" id="yiv9248003856yqt41586"><div id="yui_3_16_0_1_1456986574653_3814"><div dir="ltr">That's a smart idea. I would also tie that valve actuation mechanically into the actuation mechanism for the hatch dogs, so it remains intuitive and doesn't require a second action.</div>
<div dir="ltr" id="yui_3_16_0_1_1456986574653_3818">Sean<br clear="none">
</div>
<br clear="none"><br clear="none"><div class="yiv9248003856gmail_quote" id="yui_3_16_0_1_1456986574653_3813">On March 2, 2016 9:05:54 PM MST, Alan James via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<blockquote class="yiv9248003856gmail_quote" style="margin:0pt 0pt 0pt 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex;" id="yui_3_16_0_1_1456986574653_3812">
<div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;" id="yui_3_16_0_1_1456986574653_3811"><div><span>Yes, didn't think of the pressure you get when you open the door.</span></div><div><span>You would need to have a valve to release the vacuum before being able</span></div><div dir="ltr"><span>to open the door, perhaps this valve could be a 3 way valve, letting air in between the o-rings</span></div><div dir="ltr" id="yui_3_16_0_1_1456986574653_3810"><span>& closing the flow to </span>the transducer simultaneously. This would stop a low pressure transducer </div><div dir="ltr">being destroyed & stop the vacuu!
m pump
cutting in as it would maintain a vacuum in the line.</div><div dir="ltr">Cheers Alan</div><div><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 dir="ltr"> <font size="2" face="Arial"> </font><hr size="1"><font size="2" face="Arial"> <b><span style="font-weight:bold;">From:</span></b> Brian Cox via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none"> <b><u></u>To:</b> Personal Submersibles General Discussion <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> <br clear="none"> <b><span style="font-weight:bold;">Sent:</span></b> Thursday, March 3, 2016 4:32 PM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> Re: [PSUBS-MAILIST] Hatch interlock<br clear="none"> </font> </div> <div><br clear="none"><div><div style="font-family:Arial, sans-serif;font-size:10pt;"><div>Sean, If you are only vacuuming that 1" or so circle in-between the O rings will the vacuum be enough to hold it? Seems like you'd have around 280# pounds with a 10 Hg vacuum. or you could have close to a total vacuum? 25 Hg ? then you could get upwards to 700# + , If the O rings squeezed all the way down you might get metal to metal, then would y!
ou still
reap the benefit of that area acting as a force? Seems like there would be very little volume of vacuum. </div><div> </div><div>Brian<br clear="none"><br clear="none">--- <a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a> wrote:<br clear="none"><br clear="none">From: "Sean T. Stevenson via Personal_Submersibles" <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none">To: Personal Submersibles General Discussion <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none">Subject: Re: [PSUBS-MAILIST] Hatch interlock<br clear="none">Date: Wed, 02 Mar 2016 14:53:19 -0700<br clear="none"><br clear="none"></div><div dir="ltr">I will have one transducer per hatch, so that I can track the interlock status and seal integrity per hatch. Each transducer is therefore exposed to whatever pressure exists at the flange between orings, which in the case of the lockout hatches must necessarily include the pressure at full lockout depth, because those flanges are exposed to full pressur!
e when
the lockout is operated. This means that in order for this conceptual design to work, I must accept a larger range, lesser resolution measurement for those hatches, but it occurs to me now that in every case, I would need to accommodate the maximum anticipated pressure on either side of each hatch, if I expect to be able to track progressive seal leakage without damaging a transducer. Ergo, only the 1 atm spaces could make use of 0 - 15 psia transducers. The rest would have to be 0 - 250 psia or whatever, and I may require higher resolution signal conditioning (24 bit?) to eff!
ectively
measure the range below 1 ata.</div></div>
<div dir="ltr">Sean<br clear="none">
<br clear="none"><br clear="none"></div><div>On March 2, 2016 1:19:54 PM MST, Alan James via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<blockquote style="margin:0pt 0pt 0pt 0.8ex;padding-left:1ex;border-left-color:rgb(204,204,204);border-left-width:1px;border-left-style:solid;">
<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>Sean,</div><div>why not leave the transducer in the 1 atm compartment & just attach it</div><div dir="ltr">to the pipe from the compressor that would run through the wall to the various</div><div dir="ltr">compartments & sealing flanges. There are of course other complications with</div><div dir="ltr">releasing the vacuum pressure on the individual hatches.</div><div dir="ltr">Alan</div><div dir="ltr"><br clear="none"></div><div><br clear="none"><br clear="none"></div><div style="display:block;"> <div> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div dir="ltr"> <font face="Arial" size="2"> </font></div></div></div></div></div></blockquote></div><hr size="1"><font face="Arial" size="2"> <b><span style="font-weight:bold;">From:</span></b> Sean T. Stevenson via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none"> <b><span style="font-weight:bold;">To:</span></b> Personal Submersibles General Discussion <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> <br clear="none"> <b><span style="font-weight:bold;">Sent:</span></b> Thursday, March 3, 2016 8:35 AM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> Re: [PSUBS-MAILIST] Hatch interlock<br clear="none"> </font> <div><br clear="none"><div><div><div dir="ltr">It is not the personnel transfer hatch that presents the problem, but rather the egress hatches in the lockout chamber, as those flanges will!
see the
lockout pressure in normal operation. I can get away with a larger range pressure transducer for those hatches, but then I lose measurement resolution.</div>
<div dir="ltr">Sean<br clear="none">
</div>
<br clear="none"><br clear="none"><div><div>On March 2, 2016 9:32:49 AM MST, Alan James via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<blockquote style="margin:0pt 0pt 0pt 0.8ex;padding-left:1ex;border-left-color:rgb(204,204,204);border-left-width:1px;border-left-style:solid;">
<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>Sean,</span></div><div dir="ltr"><span>that sounds a good idea. Nuytco set the o-ring on the deep worker hatch externally with a vacuum</span></div><div dir="ltr"><span>pump, but with your twin seal idea you could do this from within the sub without decreasing the hull pressure.</span></div><div dir="ltr"><span> If the transducers are just monitoring the vacuum between the o-!
rings
can't the transducer be</span></div><div dir="ltr"><span>m!
ounted
on the 1atm side of the diver lockout hatch & not be exposed to diver lockout pressure?</span></div><div dir="ltr"><span>Alan</span></div><div dir="ltr"><span><br clear="none"></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 dir="ltr"> <font face="Arial" size="2"> </font><hr size="1"><font face="Arial" size="2">
<b><span style="font-weight:bold;">From:</span></b> Sean T. Stevenson via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none"> <b><span style="font-weight:bold;">To:</span></b> "<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>" <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> <br clear="none"> <b><span style="font-weight:bold;">Sent:</span></b> Thursday, March 3, 2016 1:41 AM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> [PSUBS-MAILIST] Hatch interlock<br clear="none"> </font> </div> <div><br clear="none"><div><div dir="ltr">Doing some further design on my lockout submersible project, I came up with a novel way to implement hatch interlocks, which doubles as a seal condition monitor, !
and a
means of establishing a preliminary seal in the absence of a pressure differential without relying on the hatch dogs to p!
rovide
the initial o-ring squeeze.</div>
<div dir="ltr">My design entails two o-rings per hatch (vessel has six hatches: cabin loading / escape, outer lockout loading / escape, inner lockout loading / escape, inner lockout egress , outer lockout egress, and transfer). These o-rings are concentric face seals, each residing within a half dovetail groove for positive retention of each o-ring when the hatch is opened or manipulated. The grooves are oriented such that the flat face of each half dovetail faces the intermediate space between the two rings. This intermediate volume is not isolated, but rather connected (on the sealing flange side) to a vacuum transducer, and piped through appropriate valving to a vacuum pump. When the hatch is closed, this intermediate space is pulled to vacuum (as strongly as the pump allows), then locked off, and the strength of this vacuum is measured by the transducer and continuously monitored. The interlock is clear as long as the va!
cuum
holds, a!
nd
activates the moment the seal is rele!
ased,
instead of relying on some arbitrary movement of the hatch to indicate that it is open.</div>
<div dir="ltr">Apart from the obvious expense, I see a potential problem with exposing those vacuum transducers in the lockout hatches to high pressure, necessitating either a less sensitive transducer that will withstand the pressure, or some means of isolating the transducer when the pressure approaches the limit of its range - I'm still working this out in my head, but I thought I would share anyway.</div>
<div dir="ltr">Sean<br clear="none">
</div>
</div><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"><br clear="none"><br clear="none"></div> </div> </div> </div></div><div style="margin-top:2.5em;margin-bottom:1em;border-bottom-color:rgb(0,0,0);border-bottom-width:1px;border-bottom-style:solid;"></div><pre></pre><hr><br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></blockquote></div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div> <div style="margin-top:2.5em;margin-bottom:1em;border-bottom-color:rgb(0,0,0);border-bottom-width:1px;border-bottom-style:solid;"></div><pre></pre><div></div><hr><br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none">_______________________________________________
Personal_Submersibles mailing list
<a rel="nofollow" shape="rect" href="">Personal_Submersibles@psubs.org</a>
<a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a>
</div><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"><br clear="none"><br clear="none"></div> </div> </div> </div></div><div style="margin-top:2.5em;margin-bottom:1em;border-bottom:1px solid #000;"></div><pre></pre><hr><br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></blockquote></div></div></div><br clear="none">_______________________________________________<br clear="none">
Personal_Submersibles mailing list<br clear="none">
<a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none">
<a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none">
<br clear="none"></blockquote></div></div></div><br><div class="yqt6536156463" id="yqt09051">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">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></body></html>