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whenever I route parallel traces on Altium, I get those narrow ground pours between my signal traces when I fill my ground planes. A collegue told me: since these pours are narrow and thus high impedance compared to a ground plane, they would pair with the signal lines, and I should avoid this and remove those narrow pours (I thought parallel ground was good, though?). I wanted to remove these small pours in Altium, but since they don't fit as islands or dead copper, they are still filled. I cannot find a sleek way to do this except by placing awkward shaped polygon cutouts over my traces

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Is there a clean way to cutout these "partial islands" of ground pour on Altium? Thanks!

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  • \$\begingroup\$ Shuffle those vias a little bit closer. \$\endgroup\$ – Andy aka Dec 16 '20 at 15:29
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You can "Remove Necks Less Than ____", on the properties tab for that polygon. Then set the distance to whatever makes sense in your case.

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Unchecked:

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Checked:

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  • \$\begingroup\$ Brilliant! thank you. Was my colleague right about the fact that these high impedance necks are best avoided? \$\endgroup\$ – JCSB Dec 16 '20 at 15:41
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    \$\begingroup\$ You are very welcome! In short, yes he was right, especially if you cannot make the ground pour connect to low impedance ground in both ends (and if you already have a solid pour underneath you don't really need parallel ground). A quick search returned this other SE post: electronics.stackexchange.com/questions/233183/… - but basically on the high frequency side, think that the current will want to return as close as possible to the trace - if the reference plane has a discontinuity then its not really useful for that. \$\endgroup\$ – Wesley Lee Dec 16 '20 at 16:00

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