Hi Pepe, I will be at IBC, so that may be possible...
I don't know of anyone local to you that can help - maybe someone on this list can recommend someone?
But, have you checked using the CalImages you can download from the Light Illusion website?
They may help, combined with the info on the Date/TV Level info web page.
A very basic check is to look at 'black' with no signal going to the display, and then with the Brightness Cal image check for both clipping and that the blackest black in the Cal image is as black as when there is no signal going to the display.
Then check with the Contrast Cal image for white level.
And see: http://www.lightillusion.com/display_calibration.html
Mob Boss at Light Illusion