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Thanks, Tony. Yes, I have occasionally been able to buy from Mouser and Digikey without paying the huge devilry charges. I have found a solution to the trimmer pot: I have some with the same layout as TO-5. Now I'm looking for the footprint of Alps RK11K114, which is a spindle pot, the filter frequency control. I have found the dimensions from Mouser., but obviously I will try to follow up your extensive advice about Farnell and ECAD.

You can probably find the find the parts you want in Farnell too, as well as Digikey an Mouser, from whom you can also buy components in the UK, although Farnell is much quicker, and sometimes cheaper. (I still even use Farnell in France, although the stock is mostly held in their Leeds warehouse.) Farnell has ECAD files (schematic symbols, footprints and 3D models) for a large percentage of the components they stock, including lots of trim-pots. What specific parts do you want?

To download the ECAD files, you will have to create a profile on . Almost all the major component retailers use this, which is run by SamacSys and based in the UK. It seems to have by far the most files available. If they don't have the ones you want, you can request that they create them. My experience is that they do this generally in 24hrs or less. Farnell's ECAD files link takes you straight to the login dialogue, but prefixed by "farnell.", but the same login profile will work for all retailers.

To use KiCad effectively, you have to learn how the library system works, and how manage to manage it, even if you never make any symbols and/or footprints yourself.

KiCad deals with schematic symbols and PCB footprints differently. For symbols, each library is one file and may contain many symbols. For footprints, each library is a separate folder, with individual footprint files of type "kicad_mod". Footprints are easier to deal with.

To create a personal footprint library, as opposed to one of the supplied "standard" libraries, you can create it yourself in Windows Explorer.

1. Decide where you want to keep it, and then simply create a new folder.
2. Give it a name, e.g.: "MyFootprints.pretty". Don't forget the ".pretty" bit. KiCad will not see it unless it has that naming format. If you download a lot of footprints, you might want to catalogue them separately into types along the same lines as the "standard" libraries.
   
3. Then from the top level KiCad application: Preferences > Manage Footprint Libraries. When you click on that, you will get a list of currently available libraries. There are two types: Global Libraries, which can be accessed by any KiCad project, or Project Specific Libraries that are in the current project folder.
4. To add a new global library to your list, click the "Global Libraries" tab and click on the folder icon (tooltip "Add Existing").
   
5. This will open an Explorer dialogue, in which you can navigate to "MyFootprints.pretty" that you just created. Highlight the folder, and click [Open].

That's it. "MyFootprints.pretty" will now by visible from the pcb and footprint editor apps. Any ECAD files that you download should initially be placed in that folder. Almost always, they are zipped, so you will have to extract what you need from the zip. Footprints, which have the .kicad_mod file suffix will now be available from the footprint chooser.

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Regards,
Tony

On 24/08/2024 11:33, John Woodgate wrote:

Thank you, Reinier.

You make it sound simple, but for someone who has never done it successfully, it is not simple.? I have tried and failed too often. There are many steps and questions:

1. How to make a library, what filename to use and where to save it?
2. Moving a pad is fairly easy, but how to know what to re-size it to?
3. How to change the contour lines? Are they lines or rectangles or circles? Some appear to be polygons made of individual lines, so are very difficult to change.
   

I can't use YouTube videos because I am too deaf to understand the sound. It's not a loudness problem, the people talk too fast and not clearly enough.I will certainly look at Digikey and Mouser, but I am in England, so many of their parts are simply too costly to buy in small quantities.

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OOO - Own Opinions Only
Best Wishes
John Woodgate
Keep trying