Always remember that, when it comes to time travel, the problem isn't the time part, but the space part. If you travel 30 years back in time, you would end up about 551,880,000,000 km from Earth, which is how far Earth has moved because of how fast our galaxy moves through space.
That's roughly 100 times further away than from here to Pluto. So if you have ever wondered where all the time travelers are. Well, there are out there, floating in space forever. ;)