Check your environment?
- Horizontal bars normally indicate channel interference and happens when high air pressure (which brings fine weather) allows signals to reach areas they would not normally reach. This can cause the signal to become weaker in low-lying areas. There unfortunately is no solution to this. Reception will only improve when the weather changes.
- If your TV reception deteriorates during heavy rain and is still poor when the rain has passed, check if water has penetrated into the aerial or the cable running down from it.
Is the problem solved?