'popodom' wrote:
| Ok, I get it...
| I tried it and it worked !!!
|
| Thanks a lot for your help.
_____

I am happy the suggestion worked. I am not completely familiar with
European AC plugs, so I could not be more specific with the description
without looking up the shapes. In the USA the AC plugs have two flat blades
(HOT and NEUTRAL) and one round pin (GROUND.) The two flat blades are HOT
and NEUTRAL because the AC wiring is 120 volts in the wall, but 240 volts to
the house, three wires (HOT NEUTRAL HOT), with 120 volts between each HOT
leg and NEUTRAL. In Europe the connectors are various, with two HOT and one
GROUND (EARTH.) In both specifications the GROUND (EARTH) connection is for
safety; it is connected to any metalic chassis so that a fault that delivers
current to the chassis will short to GROUND (EARTH) and cause a fuse to blow
or circuit breaker to trip.

What you were seeing on the screen was the result of a 'ground loop', a
small AC current (50 Hz in Europe) on the TV signal caused by a a small
potential difference between the laptop power supply groundn (earth) and the
TV ground (earth.) The diagonal stripes were the 'beat note' between the
approximate 50 Hz of the power line and the very slightly less than 50 Hz of
the TV field rate.

Lifting the ground (earth) connection at the laptop power supply allows the
laptop/power supply to 'float' to the same potential as the TV. I guess the
problem could also be the TV power supply or ground (earth). It might be a
good idea to get the TV checked for proper grounding and operation, just for
safety, and to avoid damage to your laptop.

Phil Weldon

"popodom" wrote in message
oups.com...
Ok, I get it...
I tried it and it worked !!!

Thanks a lot for your help.

David
-----------------------------
Bon, ben, le problème est résolu.
Il semblerait que la prise de terre pose problème.
Il suffit de brancher le transfo sur une prise sans terre et ça marche
!
Une prise sans terre, c'est une prise à 2 broches et non 3 broches.

Bien à vous !

David