Hi lanicek, Stepping is supported in ngspice but implementing it in EasyEDA is a problem right now. I will try to explain why. 1) The `.step param C list 1u 2u` syntax you tried is not supported in ngspice. 2) Instead, ngspice supports repeated analysis runs in ngspice by using a short script inside of a `.control ... endc` section. There is more about this in Section `16.13.4.2 .step` in: <http://ngspice.sourceforge.net/docs/ngspice-manual.pdf#subsection.16.13.4> 3) **but** the way EasyEDA reads a schematic and then interprets it in the server, runs the simulation and then assembles the plot data before sending it back to the user, the results from earlier simulations end up being overwritten by the last one. This is not a good place to be because stepped analyses are such a powerful and fundamental feature of a simulation tool but it is some way down the To Do list below features such as a User API and an Autorouter. What will help though is if you would be prepared to submit a Feature Request. That will help bump it up the To Do list and the more people ask for it (actually not many so far!) the more attention it will get. For simple circuits, a workaround is to simply copy and paste the circuit, driven by the same or exact copies of the signal source, make sure the net names are unique and then edit the relevant component values in the two circuits. Put in two probes and then when you run the simulation you'll get the results from both circuits on one plot. Not much use if you want to do 10 runs or even a 1000 run Monte Carlo Analysis so I guess this is not the answer you'd like but I hope it gives you an understanding of where this issue is within EasyEDA. :)

I forgot to say: we are also aware of the problem you found when trying to create a curve tracer for device characteristics (like in your blog). Again, ngspice supports the creation of this type of plot but the way EasyEDA constructs it breaks the technique. Here's an attempt at a curve tracer that I tried to make work a few months ago: <https://easyeda.com/file_view_almost-a-bjt-curve-tracer-but-not-quite_uUOIZTbtn.htm> You can see it shows all the same retrace problems that you found in your blog.

thanks, I try it