I've just started putting the projector together (plog soon) and I'm using the Hyundai L72S, LL Eballast, and the Philiips ED28 400W bulb.

When I have the LCD on (no video input) I get the nice floating "No Signal" screen and it's perfectly clean. Once I power on the bulb, after about 1 to 2 minutes, when it starts getting nice and bright, white lines start appearing randomly all over the LCD, flickering in and out.

When I power it off, wait for about 20 mintues, then try again, the same thing repeats. It's clean at first, then chaotic.

They were using the same power source first and then I tried seperate power sources as I read of people having that problem. The power cables for the ballast are on the opposite side of the box than those for the LCD power board. The boards for the LCD and the ballast are in the front of the box together. Will this be an interference issue?

Any suggestions?

Thanks all!

If you can try to move you ballast away from the LCD

Alright, I positioned the eballast vertical against the front of the box and that eliminated a lot of the white line/noise problem so I'm convinced it's the ballast. When I started to get some occasional noise with it in this position, I put my hand near the eballast and then noise disappeared.

Is this normal with the LL eballast? Does it have an internal problem? Is there anything I can do, maybe wrap it in something, to prevent the noise? I'm reeeeeeeally not wanting to move the ballast to the back of the box.

Thanks all!

SupraGuy had the same problem I think. He added an EMI filter on the power line and it solved the problem. Might want to Pm him and find out how to do it.

I found a schematic for an EMI filter. It looks like this:
Click to view attachment

You can also buy EMI filters, but if you're not sure, then this is a good way to go. You MUST ensure that all parts are capable of passing the full power that your projector may draw. This means that the capacitors must be rated for high voltage, AC power, and the inductors must be able to deal with the current demands.

A simple 0.1uF capacitor rated for 250VAC will also act as a simple filter. Just put it across the live and neutral wires. This may not get it 100% clean, but it may get it clean enough that your LCD works right.

Thanks for all the info. Are the ferrite snap-on filters worth anything? I found some on ebay that were pretty cheap but I can't tell anything on specs or if they'll do the job.

http://cgi.ebay.com/5-Ferrite-Snap-On-EMI-...1QQcmdZViewItem

If the location of the eballast has an effect, and moving your had nearby has an effect, you might want to try building a simple EMF shiedl; a faraday cagr.

Surround the ballast almost completely with a conductive substance (for example, aluminum cladding). Make sure that it does not make contact with any par of the ballast, except for the cables entering and elaving the ballast. Once done, this might eliminate the effect on it's own, but if not then you can complete the faraday cage by connecting the shield to ground (easy in the UK, just hook it up to the Earth pin on any socket. IIRC, US sockets don't have an earth, so you might need to connect to something that contacts the ground such as a radiator pipe).

Edz, I tried putting sheets of aluminum around it and that made no difference. When my hand was above the ballast there'd be no noise. Now I hooked up the VGA cable and there's always noise.....dang. Have to find some way to eliminate this interference.

Run a separate power line to the LCD. I had the same LCD and it worked for me.

If you've got a standard signal cable (PC to LCD) then it's probably already got them (the 'bulges') in the cabling.

I have read posts before where people have needed to use extension cables inside their PJ, using the ferrites helped reduce noise in those cases.

It's probably the cheapest thing to try anyway.

Thanks everyone for all of the information. Here's the update with some success. I was getting the noise without even having the VGA cable hooked up.

Then I ran a cable through the top of the box to the LCDs video input and was still getting noise. Then I drilled a hole in the opposite side of the box for the video input, swapped the LCDs video and power boards around so that the power board was closest to the ballast as opposed to the video board. I also added the ferrites to the ballast power lines. I found them for $2.37 each at Fry's Electronics.

When I fired it up the first time there was a little bit of occasional noise and it eventually went away. Now I've fired it up a few times and watched a couple movies and the noise appears to be gone. Maybe it was just the ballast getting situated and burned in? Regardless, the problem seems to be solved.

I will attach a picture of the current setup within the next day or two so that anyone in the future might have an idea of how to solve this.

Thanks again!