I'm currently working on a bit of code to calculate satellite passes for a groundstationground station. I've found a variety of references that discuss the conversion form other coordinate reference frames to the local horizon (lat, long, radius to target) frame. Aside from other issues it would be really beneficial to have a worked step-by-step example of how to get from Earth centred initial-centered inertial (ECI - as output by SGP propagators) to the local horizon frame. Either a worked example-example in an answer toor a web link to a worked example would be great!
This might come under homework style question - if so DON'T delete the question, once I've figured it all out I'll make an answer with a worked example; I think this would be useful to the community.
I'm currently using this reference: Transformation to local horizontal coordinates, I'm stuck on step 3 - conversion matrix.