This TV has been doinghtis for years and was given to me. I would not
mind taking it to a shop but it is very heavy and my wife is expecting
a baby any day now.

Is there a way I can "attempt" to do this at home?

What exactly is the problem? I will have to get the numbers tomorrow.
For some reason it only does it on over the air channels that are not
really strong. Strong signal channels and satelite do not cause the
problem.