It needs to re-download the info. If that doesn't happen by itself call RCA and
with the model number they can give you the correct instructions to
re-initialize the data. This is a by product of certain repairs and there's
nothing anyone can do about it.

In fact, you are obviously on the internet, RCA's (Thompson) site might give
you the proper procedure. For some models all you have to do is unplug it for a
certain amount of time.

The TV man probably ran the set with no antenna when the physical repair was
done. He did nothing wrong here, sometimes there are safety reasons to leave
the antenna unplugged. If that's the case, all you have to do is unplug it
overnight and it'll be fine. Complications may arise if you use a cable box.

JURB