There are many alternatives to QUCS for Linux if you are looking for a replacement. The best Linux alternative is Circuit Simulator, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 25 alternatives to QUCS and ten of them are available for Linux so hopefully you can find a suitable replacement. Other interesting Linux alternatives to QUCS are Ktechlab (Free, Open Source), Circuit Simulator (CircuitJS1) (Free, Open Source), Ngspice (Free, Open Source) and Oregano (Free, Open Source).
KTechLab is an IDE for microcontrollers and electronics. It supports circuit simulation, program development for microcontrollers and simulating the programmed microcontroller together with its application circuit.
This electronic circuit simulator is highly interactive giving the feeling of playing with real components. It's very helpful for experimentation and visualization. It's a desktop version of the Circuit Simulator.
Ngspice is a mixed-level/mixed-signal circuit simulator. Its code is based on three open source software packages: Spice3f5, Cider1b1 and Xspice. Ngspice is part of gEDA project, a full GPL'd suite of Electronic Design Automation tools.
Physical things are great. Hardware companies like Apple, Arduino, etc are disrupting our lives in a big way. At BrainBox we love hardware hackers and are in absolute awe of their awesome design and applications they build.
Xyce (zi¯s, rhymes with “spice”) is an open source, SPICE-compatible, high-performance analog circuit simulator, capable of solving extremely large circuit problems by supporting large-scale parallel computing platforms.