5 ms·

QucsStudio – HF Circuit and EM Field Simulator

32 points by exar0815 5y ago

hatsunearu 5y ago
Has anyone gotten this to work? I was trying to use this as a free alternative to ADS but this didn't seem to quite work.
- ul5255 5y ago
  not tried myself but here is some documentation: http://www.gunthard-kraus.de/qucsstudio/index_english_qucsstudio.html http://www.gunthard-kraus.de/qucsstudio/index_english_qucsst...
- jimmyswimmy 5y ago
  Well, I used it for a class, and it was fine for class purposes. I did notice significant differences in modeled circuit performance between versions of Qucs Studio, for even very simple models. Instead of trying to get to the bottom of that problem, I just used the same version as the instructor and called it "good enough." But "good enough" for a class is definitely not "good enough" for the workplace. Either I was doing something stupid (quite likely) or you should stick with ADS.
- buescher 5y ago
  I haven't tried QucsStudio but Qucs has worked when I tried it. It's too bad development on Qucs seems to have stalled. My favorite fast, simple, and free linear simulator is still Puff: https://www.pa3fwm.nl/software/puff/ https://www.pa3fwm.nl/software/puff/
  - hatsunearu 5y ago
    Thanks!
  - themulticaster 5y ago
    Actually the development of Qucs is ongoing, it's just that they are a little late on making the jump from Qt 4 to Qt 5, so Qucs isn't in available in some distributions that removed Qt 4 at the moment (e.g. Arch).
- Sanzig 5y ago
  It works quite well for linear network simulations (eg: plugging together black box S-parameters from manufacturer data or extracted from a VNA) and it works reasonably well for filter synthesis. I've never used the harmonic balance simulator or the new planar EM sim though.
dennise3000 5y ago
Please guys support the original qucs instead of qucs studio which is not open source but closed and users are dependent on the good will of the author.
- wrycoder 5y ago
  Right! And qucsStudio is Windows only, I believe. Qucs runs on Linux, MacOS, and Windows. http://qucs.sourceforge.net/ http://qucs.sourceforge.net/
- madengr 5y ago
  Why? From a quick review of the videos, he has added some impressive features such as harmonic balance and planar EM. Then again, it’s nowhere near the professional tools such as Microwave Office, so I’ll continue to pay for those.
  - buescher 5y ago
    It's amazing how much is in Qucs already. I'll have to take a look. Agreed that the professional tools have a long and deep head start - I couldn't justify spending my time wrangling Qucs either.
- williria 5y ago
  Yes, QucsStudio is closed but it is improving, with the sole work of one maintainer. He asked for some support, without much success. Also, although it is closed, check the improvements of QucsStudio over Qucs and see if he only cloned the project and said it is his or if he really care about a better simulator. Also to be clear, Qucs helped me a lot when I was searching free and open source simulator, and even showed me the world of open source, but the latest release is from 2017. QucsStudio still improving, and improving. Site, docs, tutorials, etc. As both are good projects, and one is the foundation of the other, I think both deserve some credit and support.
- welterde 5y ago
  Isn't qucs licensed under the GPL? Which would make that quite illegal.
petschge 5y ago
What does this offer over say LT-Spice?
- jimmyswimmy 5y ago
  Good for RF sims. It's free compared to ADS which is NOT. You can use LTSPICE for some kinds of e.g. transmission line models but it doesn't have things like the Smith chart built in. You also can use Qucs for modeling things you'd normally use SPICE for but the library isn't there, so it's not worth the trouble. Basically, two different tools for completely different sets of problems.
Badfood 5y ago
What would experts here recommend for simulating 5ghz and 10ghz USB 3 on a particular gerber file and layup? I've been avoiding it and spinning boards making small changes hoping for the best but still having issues. And don't have the resources to buy a scope capable of doing an eye diagram at 10ghz Also bonus question.. How good are the simulations? Am I likely to be able to iterate on my layout and improve the eye diagram and order boards which have a good chance of working?

32 points by exar0815 5y ago

Has anyone gotten this to work? I was trying to use this as a free alternative to ADS but this didn't seem to quite work.

ul5255 5y ago
not tried myself but here is some documentation: http://www.gunthard-kraus.de/qucsstudio/index_english_qucsstudio.html http://www.gunthard-kraus.de/qucsstudio/index_english_qucsst...
jimmyswimmy 5y ago
Well, I used it for a class, and it was fine for class purposes. I did notice significant differences in modeled circuit performance between versions of Qucs Studio, for even very simple models. Instead of trying to get to the bottom of that problem, I just used the same version as the instructor and called it "good enough." But "good enough" for a class is definitely not "good enough" for the workplace. Either I was doing something stupid (quite likely) or you should stick with ADS.
buescher 5y ago
I haven't tried QucsStudio but Qucs has worked when I tried it. It's too bad development on Qucs seems to have stalled. My favorite fast, simple, and free linear simulator is still Puff: https://www.pa3fwm.nl/software/puff/ https://www.pa3fwm.nl/software/puff/
- hatsunearu 5y ago
  Thanks!
- themulticaster 5y ago
  Actually the development of Qucs is ongoing, it's just that they are a little late on making the jump from Qt 4 to Qt 5, so Qucs isn't in available in some distributions that removed Qt 4 at the moment (e.g. Arch).
Sanzig 5y ago
It works quite well for linear network simulations (eg: plugging together black box S-parameters from manufacturer data or extracted from a VNA) and it works reasonably well for filter synthesis. I've never used the harmonic balance simulator or the new planar EM sim though.

dennise3000 5y ago

Please guys support the original qucs instead of qucs studio which is not open source but closed and users are dependent on the good will of the author.

wrycoder 5y ago
Right! And qucsStudio is Windows only, I believe. Qucs runs on Linux, MacOS, and Windows. http://qucs.sourceforge.net/ http://qucs.sourceforge.net/
madengr 5y ago
Why? From a quick review of the videos, he has added some impressive features such as harmonic balance and planar EM. Then again, it’s nowhere near the professional tools such as Microwave Office, so I’ll continue to pay for those.
- buescher 5y ago
  It's amazing how much is in Qucs already. I'll have to take a look. Agreed that the professional tools have a long and deep head start - I couldn't justify spending my time wrangling Qucs either.
williria 5y ago
Yes, QucsStudio is closed but it is improving, with the sole work of one maintainer. He asked for some support, without much success. Also, although it is closed, check the improvements of QucsStudio over Qucs and see if he only cloned the project and said it is his or if he really care about a better simulator. Also to be clear, Qucs helped me a lot when I was searching free and open source simulator, and even showed me the world of open source, but the latest release is from 2017. QucsStudio still improving, and improving. Site, docs, tutorials, etc. As both are good projects, and one is the foundation of the other, I think both deserve some credit and support.
welterde 5y ago
Isn't qucs licensed under the GPL? Which would make that quite illegal.

petschge 5y ago

What does this offer over say LT-Spice?

jimmyswimmy 5y ago
Good for RF sims. It's free compared to ADS which is NOT. You can use LTSPICE for some kinds of e.g. transmission line models but it doesn't have things like the Smith chart built in. You also can use Qucs for modeling things you'd normally use SPICE for but the library isn't there, so it's not worth the trouble. Basically, two different tools for completely different sets of problems.

Badfood 5y ago

What would experts here recommend for simulating 5ghz and 10ghz USB 3 on a particular gerber file and layup? I've been avoiding it and spinning boards making small changes hoping for the best but still having issues. And don't have the resources to buy a scope capable of doing an eye diagram at 10ghz Also bonus question.. How good are the simulations? Am I likely to be able to iterate on my layout and improve the eye diagram and order boards which have a good chance of working?