8
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When adding an Opamp to a circuit, you'll get a TL081:

schematic

That's not a sane default. A sane default for most questions, that wind around "theoretical" opamps would be "no type"; anything else will just imply specs that (hopefully) aren't the ones of the actually used device.

This leads to avoidable confusion, especially with beginners; for example, "why is my opamp-based PD controller unstable" is quite different from "why is my TL081-based PD controller unstable".

Thus, let's remove that default value; having that default helps noone (aside from these marginally few who are actually using a TL081, which is pretty much an obsolete part from 1977).

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  • \$\begingroup\$ I agree about an ideal op amp as a default, but you realize Digikey stocks tens of thousands of various tl081s. \$\endgroup\$ – Scott Seidman Feb 17 at 16:54
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    \$\begingroup\$ @ScottSeidman yep, that makes the TL081 as default type even less sensible. My guess is that it was the first popular FET-input Opamp, which inspired the circuit editor authors to use it as default. \$\endgroup\$ – Marcus Müller Feb 17 at 16:56
  • \$\begingroup\$ I agree this could be confusing. But I'm not sure what stackexchange can do about it, since the schematic editor is powered by CircuitLabs. I don't know if they will be willing to do custom changes for our community. Even stackexchange itself often needs a lot of pressure from its own users to implement changes, so I don't know what it will take to make CircuitLabs implement changes. \$\endgroup\$ – dim Feb 17 at 19:59
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    \$\begingroup\$ Good luck on getting any change though this site, I don't know if any feature request that had actually been implemented since I've been here \$\endgroup\$ – laptop2d Feb 17 at 20:10
  • \$\begingroup\$ @laptop2d :( you folks don't really paint a bright picture \$\endgroup\$ – Marcus Müller Feb 18 at 12:25
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    \$\begingroup\$ @marcus just an accurate picture. \$\endgroup\$ – laptop2d Feb 18 at 23:38
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    \$\begingroup\$ @laptop2d that's engineers among themselves, I guess. \$\endgroup\$ – Marcus Müller Feb 19 at 7:33
  • \$\begingroup\$ +1 if I ever sketch a circuit I almost always use inkscape, but when I use the linked circuitlab, most of the time is spent removing info. Almost all of the time TOPOLOGY is important, topology is mostly what needs to be talked around. Yes specifics are needed (R-C when dealing with filter timeconstant) but the generic 3dB is more useful then the specific \$\endgroup\$ – JonRB Feb 22 at 18:26

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