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<div dir="ltr" data-setdir="false">I suspect it was more a case that Kittredge found a 22 Khz transducer source for a good price.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Jon</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"><br></div><div><br></div>
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On Sunday, November 8, 2020, 06:21:59 PM EST, Sean T. Stevenson via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="ydpedd5010yiv0492854002"><div>At 22 kHz, it looks like they put the acoustic carrier just beyond human audible range (typically 20 Hz - 20 kHz), which makes me wonder if they wanted to keep the frequency as low as possible otherwise, perhaps to maximize range or limit multipath interference?<br clear="none"><br clear="none">Sean<br clear="none"><br clear="none">-------- Original Message --------<br clear="none">On Nov. 8, 2020, 15:15, Brian Hughes via Personal_Submersibles < personal_submersibles@psubs.org> wrote:<blockquote class="ydpedd5010yiv0492854002protonmail_quote"><br clear="none"></blockquote></div><div class="ydpedd5010yiv0492854002yqt8870279048" id="ydpedd5010yiv0492854002yqt05135"><div>
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River has mine for now, checking to see how big a deal or if possible to reverse engineer it. At 22 kHz it's an oddball com system.</div>
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Brian</div>
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