Rose Tyler
They've already got the technology. They just haven't figured out how to track him yet. It takes Rose months and more jumps than she cares to count. Sometimes she thinks she's going to be pulled apart at the seams with all the jumping back and forth through time. They warn her that the odds are against her. They tell her she's only got this one planet to work with and he's got an entire Universe plus timelines they can't ever access. She tells them she'll take her chances.

When she ends up in San Francisco 1999, the equipment malfunctions. The jacket won't work and she's so frustrated, so tired so bereft that she almost cries right there in the middle of the wharf. Instead she pulls it together like he would and finds a place to sleep for a little while. Once she's had some rest it's time for fish and chips. They're almost as good as home and they go a long way toward making her feel better.

Right then. Might as well do some research while she's here. See if she can find out if he's been here recently. If he's scheduled to show up anytime soon. Library then a call into UNIT. Despite having a plan, she doesn't act on it. She'll wander a bit more, navigate her way through the people on the wharf and enjoy the day. She's never been to San Francisco in any time.