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Gerber For fun, here's a Gerber file generated from SVG footprints drawn in GNU Emacs . Note: gerbv displays polygon pad incorrectly as circle in fast mode . You should use use normal mode for this. Or else use gerbview . 3D Model If you have properly modeled footprints (1:1 scale, XY plane of the 3D model on the PCB and origin at the center of the bounding box), then you can easily generate 3D view of the assembly. In this screenshot, you can see the generated model being rendered by view3dscene. The code expects eda:url attribute to point to the 3D model (.wrl file for VRML 2.0). The shape with eda:type="board" is used as the PCB. (require 'gerber) (setq canvas-plugin-map pcb-canvas-map) Fancy fonts on Silkscreen Do you want fancy fonts on your PCB silkscreen? You can use a Hershey font or stroke font in SVG format to achieve the desired result. A small collection of these fonts are available at https://gitlab.com/oskay/svg-fonts . Code: https://gitlab.com/at...

Now you can design and run SPICE simulation for simple circuits in GNU Emacs. Since the circuit and graphs are in SVG format, you can easily annotate and share it on the web or embed it in a document.   Video tutorial for configuring the circuit diagram, running the simulation and plotting the results is below:  Video tutorial for drawing the circuit diagram using widgets is below:   Code:   https://gitlab.com/atamariya/emacs/-/blob/dev/lisp/svg.el https://gitlab.com/atamariya/emacs/-/blob/dev/lisp/spice-mode.el   Setup: Setup is covered in following blog posts. https://lifeofpenguin.blogspot.com/2021/10/svg-widget-in-gnu-emacs.html https://lifeofpenguin.blogspot.com/2021/10/spice-simulation-in-gnu-emacs.html Additionally, we need to make special spice plugin (defined in spice-mode.el) available to canvas-mode. This makes plugin keybindings available via C-x in canvas-mode. To do this, add following to .emacs (setq canvas-plugin-map spice-canvas-map)  ...

Now you can manage and run SPICE simulation within GNU Emacs using ngspice. To visualize the output, the code uses ngspice control card to run gnuplot.   .emacs ;; Check the location of spice-mode.el (load "~/spice-mode.el") (setq spice-simulator "Ngspice"       spice-waveform-viewer "ngplot") ;; ngplot is a new custom viewer defined in elisp which uses gnuplot   Install ngspice and gnuplot # apt install ngspice gnuplot Download https://gitlab.com/atamariya/emacs/-/blob/dev/lisp/spice-mode.el . Load the file (load "~/spice-mode.el") Open a new buffer and activate mode using M-x spice-mode . Select simulator Ngspice and waveform viewer ngplot via menu or by setting variables (same as in .emacs above). Enter circuit definition. Run the simulation using C-c C-r (spice-compile). Go to error, if any, using 'next-error' ( M-x next-error or M-g n ). Plot the results using C-c C-v (spice-plot). Enter the fields (e.g. int out) to be plotted. S...

        SVG seems to be quite handy for quick note-taking. You can easily draw simple shapes, use symbols from an SVG library and augment it with some freehand drawing. Combined with excellent keyboard editing of Emacs, you'll not miss anything while taking notes. Code: https://gitlab.com/atamariya/emacs/-/blob/dev/lisp/svg.el   Installation When you are drawing programmatically, you need to be able to track nodes by unique ids. e.g. if you call (svg-circle) followed by (svg-rect) using the same id, you should end up with an SVG rectange node. With out of the box svg.el, you'll end up with SVG circle node with attributes from (svg-rect). Hence canvas mode will not work with out of the box svg.el as is.   Till my patch which addresses this issue is merged in Emacs core (see https://lists.gnu.org/archive/html/emacs-devel/2021-09/msg00798.html ), you'll need to add following commands in your init file (~/.emacs) to use it.   ;; Assuming you have downloa...