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I am a beginner and trying to simulate a cole-cole plot of a simple parallel circuit having two R, one coil and a capacitor. Image attaced, LTspice version is XVII, pc is windows7.

I've read this Q-A;[Bode plot graph: Frequency vs. Angular frequency] Bode plot graph: Frequency vs. Angular frequency but things does not seem to be the same.

When I checked out the current for R1, the graph goes well. So altered this curve from R2 to 1V/I(R2) as shown in this image in the upper left.

Then altered the vertical values; 85dB to -85dB, with the tick 5db, and clicked Nyquist. This seems works goo.

But when I alter the horizontal value; o.oohms - 1Mohms, the curve collapses.

Any tips will be very much appreciated, thanks!

p.s.; Incidentally I tried turned off [Autoranging], but the results was the same...

enter image description here

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  • \$\begingroup\$ As I understand it , Cole-Cole plots are for phaser dielectric properties in the microwave band to establish a model from data, not discrete parts <1Hz ameteksi.com/products/software/zsimpwin \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Aug 15 '18 at 3:02
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    \$\begingroup\$ Welcome to EE.SE. Can you ask a specific answarable question? \$\endgroup\$ – winny Aug 15 '18 at 6:50
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LTspice doesn't have ohms, farads, etc, in the schematic editor, all it has is units, and they are case insensitive. That is, m stands for milli (1e-3), and so does M. So what you have is a step from 1 to 1e-3. So do not bother adding ohm, it has no effect, you can just write .ac oct 50 1 1meg.

Also, LTspiceXVII orders the stepped values in increasing order, but I don't know if this also applies to .AC directives.

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  • \$\begingroup\$ Hello Concerned_Citisen, thanks. your tip was fantastic to me. I did this. \$\endgroup\$ – Chy Farm Aug 15 '18 at 14:09
  • \$\begingroup\$ @ChyFarm If you think the answer was helpful, mark it as answered by clicking on it (the select mark below the down-arrow). This will serve others, in the future, to know that the answer can be used for their problems, as well. \$\endgroup\$ – a concerned citizen Aug 15 '18 at 20:12
  • \$\begingroup\$ Concerned_Citizen, thanks again, was looking for that mark! Now did it. \$\endgroup\$ – Chy Farm Aug 16 '18 at 1:06

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