IRSIM Known Issue. No output on analyser (see screenshot1.png) If you struck against a no output on analyser, this is because the background is being drawn white, and the traces are drawn white, so the result is white-on-white, and invisible! The display was being redrawn. The Tcl/Tk version was hacked on top of the X11 version, and some things aren't properly configured for Tcl/Tk. In Magic and XCircuit, the X defaults has been moved to Tcl, where they are read from a Tcl script. In IRSIM, the properties are still controlled by X11 and the X11 resource manager. The white-on-white probably comes from a default .Xdefaults or possibly .Xresources setting "*background: white" which makes all backgrounds white by default. You can avoid this by adding to your home .Xdefaults file: irsim.background: black and then reloading with "xrdb -load .Xdefaults". (see screenshot2.png) Meanwhile, upstream is working to find a fix. Chitlesh Goorah chitlesh [AT] fedoraproject DOT org