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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Possibly an LM389 transistor array equivalent<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Synth-diy [mailto:synth-diy-bounces@synth-diy.org]
<b>On Behalf Of </b>John Speth via Synth-diy<br>
<b>Sent:</b> 19 June 2022 14:58<br>
<b>To:</b> SDIY<br>
<b>Subject:</b> Re: [sdiy] A20G545 chip, what is it?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Helvetica","sans-serif"">Photo at: <a href="https://myplace.frontier.com/~jspeth/A20G545.JPG" target="_blank">https://myplace.frontier.com/~jspeth/A20G545.JPG</a><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Helvetica","sans-serif"">I should have posted this pic first. The date code accurately indicates when I built it: 1983. So anything with origins past that date are not valid. <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Helvetica","sans-serif"">Thanks - JJS<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica","sans-serif";color:#26282A">On Sunday, June 19, 2022, 06:05:02 AM PDT, <<a href="mailto:synth1@airmail.net">synth1@airmail.net</a>> wrote:
<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:10.0pt;font-family:"Helvetica","sans-serif";color:#26282A">I'm pretty good at this if I can SEE a photo.<br>
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Paul S.<o:p></o:p></span></p>
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-----Original Message-----<br>
From: Synth-diy <<a href="mailto:synth-diy-bounces@synth-diy.org" target="_blank">synth-diy-bounces@synth-diy.org</a>> On Behalf Of brianw<br>
Sent: Sunday, June 19, 2022 3:16 AM<br>
To: John Speth <<a href="mailto:johnspeth@yahoo.com" target="_blank">johnspeth@yahoo.com</a>><br>
Cc: SDIY <<a href="mailto:synth-diy@synth-diy.org" target="_blank">synth-diy@synth-diy.org</a>><br>
Subject: Re: [sdiy] A20G545 chip, what is it?<br>
<br>
My first guess was a 74x545 octal bidirectional transceiver, non-inverting.<br>
They're 20-pin.<br>
<br>
However, that doesn't seem to fit on a SSM voice card (or into an 18-pin<br>
package).<br>
<br>
Brian<br>
<br>
<br>
On Jun 18, 2022, at 7:59 PM, John Speth wrote:<br>
> Today I was dumping old circuit boards that I built many years ago. I was<br>
stripping valuable parts from one and I found two 18 pin DIPs that are<br>
marked "A20G545" on one line and "MCE 8211" on the line below it. 8211 is<br>
the date code (1982). The other markings are a mystery. Searching for this<br>
chip online was a dead end for me. Does anybody know what it could be? It<br>
was from a board that contained an SSM 2012 VCA and an SSM 2044 VCF. I've<br>
lost the schematics. It was my design.<br>
> <br>
> Thanks - JJS<o:p></o:p></span></p>
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