Hantarex polo 28 star

[Deathadderpt]

Hi

I finally have my monitor working but the screen appears like this :




How can i solve this? i figured out out to stretch the image up and down but left and right i canīt find.

[Nipedley]

There should be another pot for pincushion adjustment, its quite often by itself. On my Hantarex MTC 9000 its white, and at the left of the board.