M3 19" EX II touch screen doing strange things in calibration

[marstc1]

Firstly, apologies if this is in the wrong area, Mods please feel free to move.


So I thought I would call on my fellow touch screen jukebox buddies for help ...  I have recently bought a pre-owned 19" monitor (no bezel) which has a 3M EX II touch screen kit attached which I plan to use with Zenpoint.

If I use the touch screen whilst touching the metal casing of the monitor with my other hand all works fine.

When I do the same test without holding the metal casing the top half of the screen appears uncalibrated.

eg. if I go left to right across the bottom half of the screen all is well however if I go right to left in the top half of the screen the mouse pointer increasingly moves ahead of my finger as I move it across the screen so that when I stop the mouse is about an inch away.

What concerns me more is I can feel a vibration coming from the screen when I use it without touching the metal casing of the monitor, similar to a low voltage electric shock so I am suspecting maybe a dodgy ground connection.


Has anyone got any ideas or experienced anything similar? if so I would love to know.

Cheers


Chris

[Kevin Mullins]

Is your EX II powered from the monitor chassis?
May want to check the actuall voltage feeding the microcontroller.
There should be an external ground wire coming off the microcontroller box. (two power, one ground) Should be grounded to the frame somewhere.