I’m going to post details of the components I used, but before that some comments on the circuit board…
The documentation provides a plan for building the controller on stripboard, which looks perfectly good (but you’ll need to add a track cutting tool to the list of required tools). I decided to go down the route of prefabricated PCBs, thinking without any real evidence that it would be simpler and more compact. There appear to be a number of different links in the documentation to “recommended” PCB providers, but I ordered from Aisler. They also offer a package for components, but ignore it. It doesn’t use the listed components and it isn’t even remotely complete. I assume someone must have started setting up a list and abandoned it fairly quickly because they couldn’t find what they wanted. My recollection is that the minimum order from Aisler is for three boards. As it happened I wanted at least three anyhow so that worked out for me. Otherwise you might need to a friend or two who also want to do the build so you can share costs.
A little later, in an exchange of emails with Robert Brown, I had the impression that he was surprised I wasn’t using stripboard for the build and that he was expecting people would do it that way. I may have misinterpreted what he was saying, but assuming I got it right that does add to the confusion given that the documentation already suggests two separate “recommended” sources for the bespoke PCB.
Had I known this to start with I’d probably have gone with the stripboard build and as I intend to build the focuser controller once the dew controller is done I will do exactly that for those, but as I had the three PCBs already ordered that’s the way I went this time. In the event that I want any more (I may build a fourth to use for my travel kit so I don’t have to remove one from the observatory) I will go down the stripboard route. If you would prefer to use a prefab PCB then I couldn’t really fault the Aisler service to be fair.