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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif">Hi Rhys,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif">This reminds me of what we used to do in vintage cars with positive ground electrics…<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif">A 24V/48V dc/dc converter will do the job giving you an ‘inverted’ +24V DC potential whilst still maintaining proper grounding, the principle is well articulated here,</span>
<span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif"><a href="https://mgaguru.com/mgtech/electric/et207.htm">https://mgaguru.com/mgtech/electric/et207.htm</a> just in reverse in your instance. Check out
<a href="https://www.powerbox.com.au/dc-dc-converters/dc-dc-converter-eta-pbih">https://www.powerbox.com.au/dc-dc-converters/dc-dc-converter-eta-pbih</a> for a suitable converter.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif">Hope this helps,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Century Gothic",sans-serif">Dirk<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="mso-fareast-language:EN-AU">From:</span></b><span lang="EN-US" style="mso-fareast-language:EN-AU"> AusNOG <ausnog-bounces@lists.ausnog.net>
<b>On Behalf Of </b>Rhys Cuff (Speedweb Internet)<br>
<b>Sent:</b> Thursday, 25 June 2020 5:19 PM<br>
<b>To:</b> ausnog@lists.ausnog.net<br>
<b>Subject:</b> [AusNOG] Positive ground<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi Group<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We just purchased a radio transmitter that requires Positive Ground.<o:p></o:p></p>
<p class="MsoNormal">We normally power with a Netonix but the Pin out is different so that’s a no go.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I can power with DC cable, problem is the unit is positive ground, everything else is negative ground.<o:p></o:p></p>
<p class="MsoNormal">It’s an off grid site, all 24v dc<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What are my options for powering this?<o:p></o:p></p>
<p class="MsoNormal">I “Think” I can just use an isolated DCDC converter but don’t want to risk letting the magic smoke out.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks for any help.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Rhys <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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