ghosting is a common problem in tv reception caused by interference of a reflected signal.
the reflected signal travels a greater/shorter distance before to reach the tv tuner and then arrives a bit later/earlier which produces ghosted pictures either to the left or to the right of the principal picture.
those that appear to the left are generally due to the ingress of the signal into the system after the headend.
mismatches also produce serious ghosting problems, they are present in devices with poor return loss specifications.
related origin can be corroded or faulty connections.
the installer can reduce this effect by re-siting the antenna or by using antennas featuring greater directivity.
in some cases it is necessary the use of stacked antennas to increase the intrinsic directivity of each antenna.
the teletext can also be affected by short delays dropping out it.
the most common origin of the problem is the reflection due to nearby building to the antenna, as indicated in the picture