<div dir="auto">I think it's a 2 stage lc low pass filter followed by a modified active bridged t.<div dir="auto"><br><div dir="auto"> My simulation of the active stage shows that the addition of the 4.7u cap and 8.2k resistor to ground change the bridged-t so that it allows some low frequency signal through. </div><div dir="auto"><br></div><div dir="auto">Very 1960s design. Can't really see why it was chosen though, seems a bit overcomplicated to me</div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Nov 30, 2022, 8:29 PM Lanterman, Aaron D via Synth-diy <<a href="mailto:synth-diy@synth-diy.org">synth-diy@synth-diy.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">



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Taking a peek here:
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<div><a href="https://modularsynthesis.com/roman/buchla296/296%20Schematics.pdf" target="_blank" rel="noreferrer">https://modularsynthesis.com/roman/buchla296/296%20Schematics.pdf</a></div>
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<div>15 of the 16 bands consist of MFB bandpass filters.</div>
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<div>But the lowpass is… something else? Look at the far right where it says “alternate section for board 1” — anyone recognize that topology? I have a suspicion that it’s something standard that I’m just not seeing because of the way it’s drawn.</div>
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<div>Aaron Lanterman, Prof. of ECE, Georgia Tech<br>
My blog on Education and Innovation: <a href="https://edupocalypsenow.wordpress.com" target="_blank" rel="noreferrer">https://edupocalypsenow.wordpress.com</a><br>
My blog on Electronics and Programming: <a href="https://lantertronics.blogspot.com" target="_blank" rel="noreferrer">https://lantertronics.blogspot.com</a><br>
My YouTube channel on Electronics and Programming: <a href="https://www.youtube.com/c/lantertronics" target="_blank" rel="noreferrer">https://www.youtube.com/c/lantertronics</a></div>
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