From what I understand, it's supposed to affect only the user. Unless you use it as an interface to a bigger, more complex time travel system like Dr. Z once theorized if I'm not mistaken. But that's another story.
Naturally there are members on here who believe that the HDR can transport people physically through time, and some of us who dont believe it can..
My own thoughts about it are it might just be possible to use it for Astral time travel, provided that the person has the ability to deep meditate firstly....after saying that it might only be an interface (as Num7 suggested) for a mind expanding system such as was used in the Montauk experiments in time, but for only one person..