Signal interference from laptop

[echo7]

I own a Benq PB6100 digital projector and have been very happy with its performance when using DVD or VHS as the source, but when using my Dell laptop as the source with both s-video and composite cables there is terrible interference. When using a VGA cable the interference dissappears.

Can someone please help me as to why this interference happens when using s-video and composite cables and also how to counteract it.

A suggestion that was given to me was something about the laptop not being 'earthed' but i'm not sure how accurate that is.

Any help would be greatly appreciated

[andyturner28]

Why would you want to use composit or s-video instead of VGA?

[echo7]

because i use my projector in different locations such as clubs and do not want to have to buy a 10m+ VGA cable.

but would the inference be anything to do with shielded cables. i don't know if VGA cables are, but would a shielded s-video cable be a solution?

[echo7]

also, if I was to use VGA would here be any problem with using a 30m cable - any type of signal degradation or any other difficulties?

[andyturner28]

I have just got a 3m VGA extention cable for my monitor and the picture is now crap with wavy lines down the left side and the whole screen is out of focus. Don't know weather i have a dud lead but i couldn't imagine what a 30m would be like.
If you wanted to give it a go www.cableuniverse.co.uk do very cheap leads i think up to 30m.
Cant help with the sheilded cable question though, i have never done a direct comparison.

Andy

[echo7]

Thanks for the info Andy. I decided to take the plunge into the exciting world of VGA cables and have order a 15m cable from ebay.

Really hope the interference your experienced doesn't occur. Will post my findings.

Thanks again.