In another topic about sharing AC and DC commons here (Any reasons for separating AC and DC grounds?) the subject of Arduinos, ITADS, Relays etc, came up. I know this has all come up before in pieces here and there, but I though it might be good to have a single thread where this was all discussed.
One of the questions that I don't think was ever answered was which of the devices below would be the best choice? (Picture shown below posted by Stan2004) Or should something else be used? If you have used any of these devices, how did you mount them on your layout? Did you build an enclosure for them, hide them in the scenery, install them between the ties in the track, etc. (pictures welcome)?
Anyway, what are your thoughts, experiences, suggestions etc. on all this? Other methods also welcome.
