<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
<META content="MSHTML 5.00.3315.2870" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV><FONT color=#0000ff face=Arial size=2><SPAN class=282104722-19122001>No
typo - Electronotes # 61, I think? (from memory, scary huh?)</SPAN></FONT></DIV>
<DIV><FONT color=#0000ff face=Arial size=2><SPAN
class=282104722-19122001></SPAN></FONT> </DIV>
<DIV><FONT color=#0000ff face=Arial size=2><SPAN class=282104722-19122001>It's a
"two-chip" VCA. Pin 4 of the 3080 does not go to -15 but is instead driven by
the control input op-amp. It's from a Walter Jung design originally I seem to
remember (scary again. huh?), and he is using the 3080 as a transistor array
rather than an op-amp with a gain control pin. The guts of the chip don't care
what kind of schematic symbol you use!</SPAN></FONT></DIV>
<DIV><FONT color=#0000ff face=Arial size=2><SPAN
class=282104722-19122001></SPAN></FONT> </DIV>
<DIV><FONT color=#0000ff face=Arial size=2><SPAN class=282104722-19122001>I used
this design for the ASM-1 since it's such a cool linear VCA. However I can't
explain the theory as well as the original Electronotes article. It was several
pages in great detail of how a 3080 is built inside.</SPAN></FONT></DIV>
<P><FONT size=2>Best Regards,<BR><BR>- Gene<BR><BR></FONT><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> Fahl, Romeo
[mailto:RFahl@extensis.com]<BR><B>Sent:</B> Wednesday, December 19, 2001 12:59
PM<BR><B>To:</B> 'Massimo Ischia';
synth-diy@dropmix.xs4all.nl<BR><B>Subject:</B> RE: [sdiy] Bernie Hutchins CA3080
VCA <BR><BR></P>
<BLOCKQUOTE style="MARGIN-RIGHT: 0px"></FONT>
<P><FONT color=#0000ff face=Arial size=2><SPAN
class=648305020-19122001>Perhaps a mislabelled schematic? Which issue of
Electronotes is it in?</SPAN></FONT></P>
<P><FONT color=#0000ff face=Arial size=2><SPAN
class=648305020-19122001>Romeo</SPAN></FONT></P>
<P><FONT color=#0000ff face=Arial size=2><SPAN
class=648305020-19122001></SPAN></FONT> </P>
<BLOCKQUOTE style="MARGIN-RIGHT: 0px">
<DIV align=left class=OutlookMessageHeader dir=ltr><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> Massimo Ischia
[mailto:prophet@libero.it]<BR><B>Sent:</B> Friday, January 18, 2002 10:12
AM<BR><B>To:</B> synth-diy@dropmix.xs4all.nl<BR><B>Subject:</B> [sdiy]
Bernie Hutchins CA3080 VCA <BR><BR></DIV></FONT>
<DIV><FONT face=Arial size=2>
<DIV><FONT face=Arial size=2>Hi,</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Can anyone explain me how works the strange
Bernie Hutchins CA3080 VCA (that with control signal on pin 4)</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Massimo Ischia<BR>Software Dpt<BR><BR>Far
Systems S.p.A.<BR>Via Fornaci, 35, 38068 Rovereto (TN) - ITALIA<BR>Tel. +39
0464 485333 - Fax. +39 0464 485334<BR>Internet: <A
href="http://www.farsystems.it">www.farsystems.it</A> <<A
href="http://www.farsystems.it">http://www.farsystems.it</A>>
<BR>E-mail : <A
href="mailto:prophet@libero.it">prophet@libero.it</A><BR><BR><BR></FONT></DIV></FONT></DIV></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>