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</head><body style=""><div>Yes it was.</div>
<div> </div>
<div>However, this circuit still uses one opamp, a resistor and at least two diodes.</div>
<div>The more straightforward approach adds two resistors, and replaces one diode by a</div>
<div>transistor. </div>
<div>So this doesn't add much in complexity and cost, and you can control both halves of an LM13700 independently.</div>
<div> </div>
<div>Best regards</div>
<div>Simon</div>
<div> </div>
<div><br>> Op 9 februari 2016 om 20:20 schreef Mattias Rickardsson <mr@analogue.org>:<br>> <br>> <br>> Aha!<br>> It *was* a beautiful trick. :-)<br>> <br>> http://electronotes.netfirms.com/AN399.pdf<br>> <br>> /mr<br>> <br>> <br>> On 8 February 2016 at 19:09, Ian Fritz <ijfritz@comcast.net> wrote:<br>> > The reference to the original Jung article is JAES, 23, 1975. This method<br>> > was widely used in EN projects. I looked at using this method with the<br>> > LM13700 to aid people who want to build off of these projects, but who can't<br>> > obtain the CA3080. It's also an easy way to improve S/N by 3dB, as pointed<br>> > out by Serge T. in his EN article from when the chip was new.<br>> ><br>> > I couldn't wade through Aaron's article either. It sounded like negating<br>> > then subtracting? Isn't that the same as adding?<br>> ><br>> > Ian<br>> ><br>> ><br>> ><br>> > On 2/8/2016 2:41 AM, Mattias Rickardsson wrote:<br>> >><br>> >> On 4 February 2016 at 05:52, <ijfritz@comcast.net> wrote:<br>> >>><br>> >>> Good grief! Just connect them directly in parallel. An example,<br>> >>> complete<br>> >>> with the W. Jung trick:<br>> >>><br>> >>> http://electro-music.com/forum/viewtopic.php?highlight=jung+ota&t=50884<br>> >><br>> >><br>> >> What does it do? What is the "trick"?<br>> >> I feel like one of the answers in that thread:<br>> >> "I hadn't heard of this trick before, is there an article somewhere<br>> >> that explains the benefit of drawing bias current from V-? I feel like<br>> >> there's something obvious that I'm missing."<br>> >><br>> >> I spontaneously found Aaron's idea potentially better than nothing,<br>> >> but I haven't plunged into it.<br>> >><br>> >> /mr<br>> >><br>> ><br>> _______________________________________________<br>> Synth-diy mailing list<br>> Synth-diy@dropmix.xs4all.nl<br>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy</div></body></html>