He explains it in his own words in the demo video. The sensor was small enough for an N-gauge train, which translates to 1:148 scale or about 9mm from rail to rail. His idea was to build a tiny ...

The video concludes with footage of the road unit leading a freight train through Southern Wisconsin and Northern Illinois. Road names on the N scale Alco RSD5 from Atlas include Atchison, Topeka & ...

For those working in the N scale, there’s now an easy way of observing your project as the train driver would see it: [Vassily98] managed to squeeze a wireless camera into an N-scale railcar.

I constructed my first N scale layout in a coffee table in 1976 based on the East Glasstop project railroad series that appeared in Model Railroader from December of 1970 to April of 1971. However, it ...