Smartboard distortion only when laptop charger plugged in

[chrbb]

One of our staff laptops distorts the smartboard image - only noticeable when the image is white, lines running up and down the smartboard image, a bit like on an old TV. This only happens when the laptop has it's charger plugged in, running on battery it's fine, no distortion.

 

I've tried a different electrical socket and charger but this doesn't help. It seems to be a combination of that laptop and that smartboard, according to the member of staff her laptop doesn't have the same effect in any other classroom.

 

Any ideas where I should be looking to sort this out?

[Oaktech]

what you are seeing is a visual representation of the distorted/ticking audio problem that people sometimes get using PA systems with laptops.

 

try plugging the laptop charger in to a range of other sockets.

 

try changing the vga for a better quality one (more shielding)

 

is the projector an NEC or one with a 2pin figure 8 power lead? it could be a grounding issue between the two, you may need to swap projectors for one with it's own ground conection (a 3 pin kettle or clover leaf lead)

[witch]

You can buy some sort of suppressor - I'm sure it was mentioned before on here somewhere.

LAPTOP HUM ELIMINATOR - GROUND LOOP ISOLATOR | eBay

might work?

[chrbb]

what you are seeing is a visual representation of the distorted/ticking audio problem that people sometimes get using PA systems with laptops.

 

try plugging the laptop charger in to a range of other sockets.

 

try changing the vga for a better quality one (more shielding)

 

is the projector an NEC or one with a 2pin figure 8 power lead? it could be a grounding issue between the two, you may need to swap projectors for one with it's own ground conection (a 3 pin kettle or clover leaf lead)

 

The projector is ceiling mounted, I've tried different sockets to no avail. Also different VGA cables. Apparently it doesn't happen with other laptops in that room.

Edited November 17, 2011 by chrbb

[Oaktech]

ok, what actual models are we talking about here? laptop and projector?

[jamesreedersmith]

Epson and Toshiba at a guess!

[Oaktech]

Epson and Toshiba at a guess!

 

i am also expecting to see NEC and possibly a dell using a pa-1650-05d power supply.

[chrbb]

Lol, toshiba and Sanyo. Narrowed it down to the laptop it distorts on another smartboard but not as much. If I hold the charger jack and wiggle it around the distortion gets worse. So am wondering if it's something to do with the charging socket on the laptop. It's under warrenty so may go back to Toshiba.