There was another one -- early-1980's, where some time traveler had a device that blinked whenever there was a problem in the timeline, and then it shifted to green once he and his associate(s) fixed it.
That was Voyagers
, which I mentioned above. It starred the late Jon-Erik Hexum as a time-traveller named Phineas Bogg (a play on Jules Verne's Phileas Fogg, for some reason), and his sidekick was child actor Meeno Peluce. The device in question was a pocketwatch that functioned as their time machine. As I said, there was never any explanation for why history wasn't going the way it "should." The whole thing was pretty much an excuse to teach history lessons to young viewers.
I remember Time Trax as well, which had a similar premise.
That was similar to Timecop
in that it involved a future cop chasing future criminals into their past, but it was different in that their time machine only went to one era, the present day of the series. And there was no changing of history involved, since they came back from an alternate timeline. (Though that didn't explain how the hero was able to send messages to the future by placing classified ads they later read in old archived newspapers.)