Ask shares some good projects of QUCS software

[abdulbadii]

Anyone please generous enough to give and share away most of good/excellent projects in the format on which QUCS software makes use of ?

Just badly felt aghast found the S/W sample/project is completely nill

as feel it the only motivation if it's fulfilled

[Bassman59]

Anyone please generous enough to give and share away most of good/excellent projects in the format on which QUCS software makes use of ?

Just badly felt aghast found the S/W sample/project is completely nill

as feel it the only motivation if it's fulfilled

I'm pretty sure that QUCS is dead. Why bother, when LTSpice and ngspice exist?

[Whales]

abdulbadii: QUCS does have example documents.  Are you having trouble finding them?  I also didn't realise they were there until I looked, they do not make them obvious. 

I found the example docs very useful for understanding how to use QUCS.

Code: [Select]

$ ls qucs_examples/
Amp_Baseband_Low-noise.pro  bpf_10Ghz.sch            groupdelay_sp.sch
Amp_Baseband_Low-noise.sch  bridge.sch               gyrator.sch
Amp_Two_Tone.dat            buckboost.dat            lc_osc.dat
Amp_Two_Tone.dpl            buckboost.dpl            lc_osc.dpl
Amp_Two_Tone.sch            buckboost.sch            lc_osc.sch
Amp_baseband_noise.dat      buckconverter.sch        lf_osci.dat
Amp_baseband_noise.dpl      charac.dat               lf_osci.dpl
BPF_1550_edge_cpld.sch      charac.dpl               lf_osci.sch
BPF_2000_Co-ax.dat          charac.sch               microstrip.sch
BPF_2000_Co-ax.dpl          chargepump.sch           mixer.sch
BPF_2000_Co-ax.sch          chebyshev1_5th.sch       mscoupler.sch
Comb_Gen.dat                classic_osci.dat         multiplier.sch
Comb_Gen.dpl                classic_osci.dpl         notch.sch
Comb_Gen.sch                classic_osci.sch         opamp_gyrator.sch
IdealBalun.sch              colpitts.dat             pentode.sch
LPF-Balun2.sch              colpitts.dpl             preregulator.sch
LPF-Balun3.sch              colpitts.sch             resonance.sch
LPF_1000_Coplanar.sch       colpitts_base.dat        rf_osci.dat
LPF_1000_Radial-Stub.sch    colpitts_base.sch        rf_osci.dpl
LPF_1250_Elliptical.sch     diff1.sch                rf_osci.sch
Puls3b.sch                  diode_hb.dat             rgummel.sch
SmithChartTest.sch          diode_hb.sch             sawtooth-1.sch
VCO_100.sch                 elliptic_5th.sch         sawtooth-2.sch
X2_100_Bipolar.sch          fet.sch                  sawtooth-3.sch
X5_500.sch                  fet_noise.sch            sawtooth-discreet.sch
active_bp.dat               fgummel.dat              schmitt.sch
active_bp.dpl               fgummel.dpl              selective_amp.sch
active_bp.sch               fgummel.sch              shot.sch
active_lp.dat               fhr01fh.sch              singleOPV.sch
active_lp.dpl               filter_optimization.sch  single_balanced.sch
active_lp.sch               flicker.sch              stab.sch
active_mixer.sch            fullwaverectifier_1.sch  supply.sch
bbv.dat                     fullwaverectifier_2.sch  swr_meter.sch
bbv.dpl                     gain.dat                 sym_osci.sch
bbv.sch                     gain.dpl                 time_resistor.sch
boostconverter.dat          gain.sch                 triode.sch
boostconverter.sch          giacoletto.sch           wilkinson.sch
bpf_10GHz.dat               gilbert.sch
bpf_10GHz.dpl               groupdelay_ac.sch



Anyone please generous enough to give and share away most of good/excellent projects in the format on which QUCS software makes use of ?

Just badly felt aghast found the S/W sample/project is completely nill

as feel it the only motivation if it's fulfilled

I'm pretty sure that QUCS is dead. Why bother, when LTSpice and ngspice exist?

No one SPICE package is the same and everyone will prefer something different.  The concept of software 'dying' is a relatively new thing, the laws of electromagnetism don't change from one year to the next.

ngspice: doesn't provide a GUI for drawing circuits; you need to get some other software to do that.  Doesn't draw graphs either?

ltspice: I prefer QUCS' option of graphs-on-schematic (rather than graphs being on separate page/window).  That and yellow>grey

qucs: I run the windows version of it under Wine because qucs uses qt4 and my distro doesn't ship those libs any more .  Navigation between part types is a bit slow.  The key shortcuts for wire (Ctrl+E) and ground (Ctrl+G) are useful but not shown in the GUI (only the full docs).  I always turn the grid dots off, they hurt my eyes.  Absolute PITA when the solver hits problems in transient analysis ("jacobian error"), but I'm not sure how other SPICE suites fare here.

micro-cap: did a side-by-side sim comparison with QUCS, it turns out QUCS was a magnitude or so faster.  Was very surprised (perhaps mc was redrawing the window each sim cycle so it could live update its graphs?).  Interface is very complicated and doesn't seem straightforward.

[RoGeorge]

Live update of the plots can be turned off in LTspice.  The simulation speed might come from the fact that QUCS is not based on SPICE, it has its own engine/solver, or that's what I was told.

Anyways, the simulation time for a given circuit, or even the success/fail to converge to a solution for either of these can vary widely by adjusting the max allowed steps/errors or other tuning parameter of the solver.  At this aspect LTspice might be advantageous because it has a wider adoption, and solutions to problems are already known, so it's easy to find online how to get out of LTspice troubles.

QUCS still have some nice RF goodies, filters, microstrips, Smith charts, etc. but other things like placing a measuring probe are cumbersome in QUCS when compared with LTspice.  That's what makes me use mostly LTspice.  Only very rare I found myself using QUCS.  QUCS has a lot of examples and a nice PDF with a few examples and how to use QUCS in general, some in the Help menu from QUCS, or online:  http://qucs.sourceforge.net/docs.html

I have QUCS installed on Kubuntu, don't recall how I solved the qt4 requirement.  I guess I've let it install all the needed dependencies, or maybe added qt4 manually, IDK.

LTspice only has a Windows installer, but works fine in Linux, too, from Wine.  LTspice charts looks more appealing to me, and are much smarter than the charts in QUCS.  For example, the charts know to put electrical units on the axes, you can add formulas from the GUI, the plot "knows" that U*I formula will measure Watts, has RMS, has useful options for Bode plots, like showing group delay or using linear instead of log, knows octaves and decades, etc.

For more plotting the data can be exported (I think both QUCS and LTspice can do that).  For example, yesterday I've fool around plotting LTspice raw data using Python and matplotlib.  There is even a Python module called "ltspice", module that can understand the data format of the LTspice raw results file.  Doesn't have implemented all the features (i.e. the Python module doesn't identify automatically the data sections for multiple parametric runs when using the .step SPICE directive, but can be easily seen from the module's sources how to grab a certain step from the data file, or how to add new features to the Python module.

LTspice can be run in batch mode, from command line, and the .net or .asc schematics can be eventually generated or edited from Python, then all the runs and data files collected and post processed, all done programmatically from Python.

Because many other physics phenomena can be simulated with electrical circuits (e.g. a mechanical weight and a spring will behave like an LC tank, water ram in a pipe can be a reflection in a transmission line, a sound absorbent material can be seen like a filter,  etc.) mixing Python with LTspice can be a very interesting combination.

[Bassman59]

I'm pretty sure that QUCS is dead. Why bother, when LTSpice and ngspice exist?

No one SPICE package is the same and everyone will prefer something different.  The concept of software 'dying' is a relatively new thing, the laws of electromagnetism don't change from one year to the next.

Software dies when its developers stop maintaining it. There doesn't seem to be much activity in the qucs SourceForge or Github repositories.

ngspice: doesn't provide a GUI for drawing circuits; you need to get some other software to do that.  Doesn't draw graphs either?

The original SPICE didn't do that, either. I used to use MacSpice which is still maintained and still works well, but editing the text files for my deck gets tedious. But, as many have noted, at least one Kicad developer is dealing with using Kicad schematics as a front end for ngspice.

ltspice: I prefer QUCS' option of graphs-on-schematic (rather than graphs being on separate page/window).  That and yellow>grey

Sure, that's nice. but it's a preference.

qucs: I run the windows version of it under Wine because qucs uses qt4 and my distro doesn't ship those libs any more .  Navigation between part types is a bit slow.  The key shortcuts for wire (Ctrl+E) and ground (Ctrl+G) are useful but not shown in the GUI (only the full docs).  I always turn the grid dots off, they hurt my eyes.  Absolute PITA when the solver hits problems in transient analysis ("jacobian error"), but I'm not sure how other SPICE suites fare here.

WINE is a pain in the ass. But to your statement about "qucs uses qt4 and my distro doesn't ship those libs any more" just adds to the impression that qucs is a dead end.

[SiliconWizard]

ngspice: doesn't provide a GUI for drawing circuits; you need to get some other software to do that.  Doesn't draw graphs either?

ngspice only takes spice netlists as input. But it does "draw graphs". It uses something called nutmeg IIRC. It comes with ngspice. You can directly plot graphs with it using nsgpice plot commands.
The GUI is rough, but it works.
Otherwise, ngspice can also generate files for gnuplot, and the graphs can be displayed using gnuplot, which is very flexible.

But KiCad has done a good job integrating ngspice with a decent GUI.

[GN89]

I think Qucs is dead because there is not enough power to keep that project running. Unfortunately there is another project QucsStudio by Michael Margraf. He develops it as closed source which is indeed problematic because we don't know how much of the original code is in there which might end up in a lawsuit when GPL was violated. Maybe we should check on that because I think the community needs a good RF design tool which is open and not closed like QucsStudio.

[wizard69]

I think Qucs is dead because there is not enough power to keep that project running. Unfortunately there is another project QucsStudio by Michael Margraf.

That just highlights that a third party could pick up Qucs and advance it to modern GUI packages.   This does however highlight a serious problem with open source which is the lack of API stability.   

He develops it as closed source which is indeed problematic because we don't know how much of the original code is in there which might end up in a lawsuit when GPL was violated. Maybe we should check on that because I think the community needs a good RF design tool which is open and not closed like QucsStudio.

The GPL is a bit of at train wreck if you ask me.    It trys to make Open Source proprietary.   If one is honestly concerned about open source they wouldn't care what happens to their source code.   The code being freely available is the only way to solve this problem of people loosing interest and code dying.   In the end the GPL makes it harder to use source released under its license, which is a huge problem for code like Qucs released under that license.

[cdev]

QUCS does RF stuff those other programs don't / can't. Like various  filters. Pair it up with NanoVNA2 and its a great idea generator for prototyping stuff..

I'm pretty sure that QUCS is dead. Why bother, when LTSpice and ngspice exist?

It likely won't become a proprietary rip-off either.  I have gotten further, faster with QUCS tI have with other SW.

[profdc9]

I use Qucs-s for many of my projects.  Qucs-s is a version of Qucs that uses ngspice.

https://ra3xdh.github.io/

Of course, you could probably use kicad as well to generate the ngspice netlist files.

I have simulations for many of my projects on my Github   http://www.github.com/profdc9/

For example:

https://github.com/profdc9/PowerAmpAudio/tree/master/Simulations   
   - audio amplifiers
https://github.com/profdc9/HighVoltageOpAmp/tree/main/Simulations
    - op amp circuits
https://github.com/profdc9/FlexibleCharger/tree/main/Simulations
    - simulations for the battery charger I designed

I also attached some simple RF amplifiers, oscillator, and mixers I modeled.

So there's some examples that may be useful to you.

Dan

[cdev]

QUCS is definitely going onto my workbench computer, I really dont have any other choice than to use it for some of the things I want to do.

Like RF filter calculations. My other choice is I can run RFSIM99 under WINE.  They overlap a bit but not as much as I'd wish.

[Gerhard_dk4xp]

I think Qucs is dead because there is not enough power to keep that project running. Unfortunately there is another project QucsStudio by Michael Margraf. He develops it as closed source which is indeed problematic because we don't know how much of the original code is in there which might end up in a lawsuit when GPL was violated. Maybe we should check on that because I think the community needs a good RF design tool which is open and not closed like QucsStudio.

Michael is the original author who got that thing rolling. Qucs studio stems from a version that is ~12
years old, which is probably pretty much the state of his time of his time at TUB. He simply
freed himself from a verbose group  of developers that did not achieve much since then.
The group just petered out. Look at what's new since then.

Some good  stuff is on <    http://www.gunthard-kraus.de/     >,
also a legal retro version of the Ansoft Designer Student Version and other interesting things.

Gerhard

[f4eru]

Kicad is much more usable and advanced those days.

[Gerhard_dk4xp]

Yes, and Porsche has a new car, and there are new trucks, too.

Qucs Studio has links to Kicad, probably not yet V7. I did not
check it, I have an own Altium Designer License for daily work.

There are also links to octave, Ikarus Verilog and GHDL-VHDK,
for example.