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<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=625531700-07112003>I
totally agree with Jay Rene's site is awesome. Also you are looking at only a
part of the necessary circuit for the complete convertor you can look
here:</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=625531700-07112003></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=625531700-07112003><A
href="http://atlas.csd.net/~rjwsoft/OctVCO_LM394_FixedSquare.html">http://atlas.csd.net/~rjwsoft/OctVCO_LM394_FixedSquare.html</A></SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=625531700-07112003></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=625531700-07112003>Cheers</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=625531700-07112003></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=625531700-07112003>Ray</SPAN></FONT></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
owner-synth-diy@dropmix.xs4all.nl
[mailto:owner-synth-diy@dropmix.xs4all.nl]<B>On Behalf Of </B>Jay
Schwichtenberg<BR><B>Sent:</B> Thursday, November 06, 2003 11:04
AM<BR><B>To:</B> synth-diy@dropmix.xs4all.nl<BR><B>Subject:</B> RE: [sdiy]
exponential converter details<BR><BR></FONT></DIV>
<DIV><FONT color=#0000ff size=2>
<DIV><SPAN class=528240018-06112003><FONT face=Arial color=#0000ff
size=2>Nick,</FONT></SPAN></DIV>
<DIV><SPAN class=528240018-06112003><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=528240018-06112003><FONT color=#0000ff size=2><FONT
face=Arial>You might try Rene's WEB site: </FONT><A
href="http://www.uni-bonn.de/~uzs159/"><FONT
face=Arial>http://www.uni-bonn.de/~uzs159/</FONT></A><FONT face=Arial>
"<FONT size=3>Whats that exp and tempco stuff?" </FONT>That will give a
general overview. The cap in the circuit is to stabilize the circuit and keep
it from oscillating.</FONT></FONT></SPAN></DIV>
<DIV><SPAN class=528240018-06112003><FONT
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=528240018-06112003><SPAN class=969320318-06112003><FONT
face=Arial>Jay</FONT></SPAN></SPAN></DIV></FONT></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
owner-synth-diy@dropmix.xs4all.nl
[mailto:owner-synth-diy@dropmix.xs4all.nl]<B>On Behalf Of </B>Nick
Liebrecht<BR><B>Sent:</B> Thursday, November 06, 2003 8:37 AM<BR><B>To:</B>
synth-diy@dropmix.xs4all.nl<BR><B>Subject:</B> [sdiy] exponential converter
details<BR><BR></FONT></DIV>
<DIV align=left><FONT size=+0>
<BLOCKQUOTE>
<BLOCKQUOTE>crap, i put the wrong URL on here. The correct
one
is<BR><BR><BR>http://darkwing.uoregon.edu/~nliebrec/Expo.pdf<BR><BR>-nick<BR><BR><BR>----
Begin Included Message ----<BR><BR>From: "Nick Liebrecht"
<nick@dreamtheater.zzn.com><BR>Sent: Wed, 5 Nov 2003 22:16:57
-0800<BR>To: synth-diy@dropmix.xs4all.nl<BR>Subject: exponential
converter details<BR><BR><BR>Hi all,<BR><BR>I am having some trouble
thinking through the typical expo converter<BR>circuit. The
circuit i'm referring to is posted here.
<BR><BR>http://darkwing.uoregon.edu/~nick/Expo.pdf<BR><BR>It's
taken from Barry Klein's book.I understand the CV
ranging/scaling<BR>part, but the actual current part is confusing me.
I recognize the<BR>actual current source built around the op amp,
but I'm fuzzy about<BR>what all the parts do, especially the capacitor.
<BR><BR>Can anyone explain this circuit to me? I want to
learn why the<BR>certain part values were chosen, and with what
equations.<BR><BR>Thanks in advance,<BR>Nick
Liebrecht<BR><BR><BR><BR>A-ren-nen-nen-ah-ren-nen-nen<BR>A-ren-nen-nen-uh-rennda<BR>A-ren-nen-nen-ah-ren-nen-nen<BR>A-rennda-rennda-rahhh
<BR><BR>---- End Included Message ----<BR><BR><BR><BR><BR><BR><FONT
size=+0>
<P
align=left>A-ren-nen-nen-ah-ren-nen-nen<BR>A-ren-nen-nen-uh-rennda<BR>A-ren-nen-nen-ah-ren-nen-nen<BR>A-rennda-rennda-rahhh
</P></BLOCKQUOTE></BLOCKQUOTE></DIV></BLOCKQUOTE></BLOCKQUOTE></FONT></FONT></BODY></HTML>