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<div>Possibly a Numera which is a JLC clone?</div>
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<div><a href="https://reverb.com/item/45328067-oberheim-ob-xa-midi-interface-archive-sound">https://reverb.com/item/45328067-oberheim-ob-xa-midi-interface-archive-sound</a></div>
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<div><a href="https://forum.vintagesynth.com/viewtopic.php?t=69628">https://forum.vintagesynth.com/viewtopic.php?t=69628</a></div>
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<div>GB</div>
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<div>------ Original Message ------</div>
<div>From "Florian Anwander" <<a href="mailto:fanwander@mnet-online.de">fanwander@mnet-online.de</a>></div>
<div>To "AH Heaven" <<a href="mailto:analogue@hyperreal.org">analogue@hyperreal.org</a>>; "*SYNTH DIY" <<a href="mailto:synth-diy@synth-diy.org">synth-diy@synth-diy.org</a>></div>
<div>Date 5/4/2024 2:02:22 PM</div>
<div>Subject [sdiy] OB-Xa unknown MIDI-Interface</div>
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<blockquote cite="cc05a597-320e-47d2-bd9e-d24c4372f55e@mnet-online.de" type="cite" class="cite2">
Hello everybody<br>
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I'm in the process of restoring my OB-Xa. In manual mode it now works perfectly, but as soon as I edit a sound from memory, all kinds of parameters are no longer correct. I suspect the MIDI interface and the 120 program slot expansion.<br>
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This is what the MIDI interface with the SRAM chip looks like:<br>
<a class="moz-txt-link-freetext" href="https://www.florian-anwander.de/oberheim_obxa/OB-Xa-MIDI-interface.JPG" moz-do-not-send="true">https://www.florian-anwander.de/oberheim_obxa/OB-Xa-MIDI-interface.JPG</a><br>
The EPROMs on the control board look like this:<br>
<a class="moz-txt-link-freetext" href="https://www.florian-anwander.de/oberheim_obxa/OB-Xa-MIDI-interface-EPROM.JPG" moz-do-not-send="true">https://www.florian-anwander.de/oberheim_obxa/OB-Xa-MIDI-interface-EPROM.JPG</a><br>
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The memory expansion obviously uses a 6116 SRAM. The original 6514 (IC109 and IC111) have been removed.<br>
I have not found a picture of an identical MIDI interface on the web.<br>
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Do any of you know which manufacturer this MIDI interface is from?<br>
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Best Regards<br>
Florian<br>
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(I've sent the same mail to the oberheim group at groups.io - sorry, if it reaches you twice)<br>
<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.florian-anwander.de/" moz-do-not-send="true">http://www.florian-anwander.de/</a></pre>
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