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<div dir="ltr" data-setdir="false">Alan,</div><div dir="ltr" data-setdir="false">I like your plan to feed O2 as needed, like a bellows add. BTW I have a new O2 solenoid valve from an Inspiration II re-breather you can have.</div><div dir="ltr" data-setdir="false">Hank</div><div><br></div>
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On Tuesday, August 20, 2019, 7:31:27 PM MDT, Alan via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="yiv1379794403"><div><div></div><div>Thanks David,</div><div>I know Cliff was getting some good results re the range he was keeping</div><div>O2 at? And that would be more difficult than in a bigger sub.</div><div>I am pretty well settled on what I am doing now, which is going with the</div><div>standard sensor, as apposed to the optical. The standard galvanic sensor I can</div><div>get anywhere but the optical I have to import from Scotland.</div><div>Also it seems simpler for me to implement with its voltage output than the data</div><div>output of the optical sensor. The optical sensor also requires a power supply.</div><div>Alan</div><div><br clear="none"></div><div class="yiv1379794403yqt9837490644" id="yiv1379794403yqt83010"><div><br clear="none">On 21/08/2019, at 11:25 AM, David Colombo 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"><br clear="none"></div><blockquote type="cite"><div><div>Hi Alan, having had the second seat in the Gamma while at Flathead for the expedition, I monitored and logged the O2 readings through out the dives. Start at hatch closure, upon reaching depth(up to 200ft+), at mid mark of the planned dive duratation and again upon accent.The variation was minor throught the dive.<div>David</div></div><br clear="none"><div class="yiv1379794403gmail_quote"><div class="yiv1379794403gmail_attr" dir="ltr">On Tue, Aug 20, 2019, 3:23 PM hank pronk 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"></div><blockquote class="yiv1379794403gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div><div class="yiv1379794403m_6419877013611324437ydpd10976c7yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div></div>
<div dir="ltr">Alan,</div><div dir="ltr">I can't speak to O2 level recovery with the hatch open after a dive, but I can say that working in the sub I have the CO2 metre on all the time if the sub is powered up. The CO2 level does not come down in a noticeable rate, in fact, just working in the sub with the hatch open, levels are 2500 and up. I would say in Gamma, the O2 level would not recover quickly. That is why I calibrate my O2 meter outside the sub.</div><div dir="ltr">Hank</div><div><br clear="none"></div>
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On Tuesday, August 20, 2019, 1:45:18 PM MDT, Alan 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:
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<div><div id="yiv1379794403m_6419877013611324437yiv2979296850"><div><div></div><div>Jon, Hank.</div><div>It would be good if someone (Hank) could measure O2 levels in the sub</div><div>& outside air to see how long it takes for them to reach an equilibrium.</div><div>You may find that leaving the hatch open for a minute is all it takes.</div><div>I am trying to build a smaller sub than the R300, so opening the hatch should</div><div>be enough to equalise the O2 levels. Also with going smaller any environmental</div><div>changes happen faster, hence the need for 3 X O2 sensors.</div><div>Alan</div><div class="yiv1379794403m_6419877013611324437yiv2979296850yqt4522119807" id="yiv1379794403m_6419877013611324437yiv2979296850yqt23940"><div><br clear="none">On 21/08/2019, at 12:24 AM, Jon Wallace 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"><br clear="none"></div><blockquote type="cite"><div><div class="yiv1379794403m_6419877013611324437yiv2979296850yahoo-style-wrap" style="font-family:times new roman, new york, times, serif;font-size:16px;"><div dir="ltr">Alan, almost all the rebreather galvanic sensors have quick disconnect adapters. I think I'm going to deal with calibration by fabricating a small handheld analyzer that I can connect the same sensor to outside atmospheric air and then reconnect back to the main processor in the vessel. The more I think of it, I will probably just make this handheld O2 sensor a separate physical module that can run on it's own power and "plug-in" to the main processor. For example, something like the "el cheapo" from oxycheq that could connect to and direct it's output to the main processor. This approach would work for the CO2 sensor as well.</div><div dir="ltr"><br clear="none"></div><div dir="ltr">Jon</div></div></div></blockquote></div><blockquote type="cite"><div><span>_______________________________________________</span><br clear="none"><span>Personal_Submersibles mailing list</span><br clear="none"><span><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a></span><br clear="none"><span><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></span><br clear="none"></div></blockquote></div></div><div class="yiv1379794403m_6419877013611324437yqt4522119807" id="yiv1379794403m_6419877013611324437yqt30504">_______________________________________________<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></div>
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