Where is TVX SDK?

Where can I find the TVX SDK? I heard it was part of Service Pack 2 upgrade for VC++. Did they remove it from SP3 (VC++ 5.0) or is this only with Visual Studio 6? I need to find out exactly what set of calls to make to disable WebTV from within a program (or by calling a small app) so other video-related programs can run, and then re-enabling WebTV after the programs have finished. Has anyone done this yet? Can anyone send me sample code and information? I can't find this stuff anywhere. I found TVXSAMP.CPP and TVXSAMPDLG.CPP, but no explanation of what is needed to call the methods or exactly what they do is listed, and I do not have the header files used for this either.

Any help at all would be great!