LCD panel distortion?

[pizzi]

I have a sharp qa-1150, works great as long as I don tput it on my Da-Lite porta scribe OHP. Every time I move the panel near the OHP the picture is distorted when I hold it about a foot away its fine, I can think of a couple of things that can cause this, just wanna ask to see if anyone can better pin point it out. Thanks in advance.

 

[pizzi]

After some testing i know its not the fan, also i found out that it only happens when the light is turned on the OHP, even 12 to 14 inches away there is still some kind of interferance, when i turn the OHP light off the distortion is gone eventho the fan still runs.....Any idea guys??

 

[gogeeta13]

its probably an unshielded light ballast. get some sheet metal and make a box to cover the ballast

 

[pizzi]

I have a 600 watt dys halogen bulb, why does this cause interferance with the sharp qa-1150?

 

[goldmoth]

are you sure its not from the heat? 600w halogen puts out a lot...

 

[pizzi]

No goldmoth because problem exist even when i just turn the OHP on and the fan is not even kicked in yet so heat is ruled out. I wish i have another OHP i can try on...

 

[gogeeta13]

did you not see my post?

its the ligh ballast. You need to shield it.

 

[zardoz]

Check for loose connections to the lamp...also look to see if your socket requires replacement, dirty or corroded contacts in the socket will arc...causing distortion and shorter lamp life. If this OHP is using an ENX lamp I doubt it even HAS a ballast. Also if it had a ballast it would have/should have been sheilded at the factory.

zardoz

 

[pizzi]

Problem is solved!!... It was the ac adapter i used a universal one that wasnt shielded or something. I got another ac adapter that was "filtered output" and bye bye interferance. Thanks all for replying and giving ideas.