CurtPalme.com Home Theater Forum

Bill in Beaumont · Joined: 28 Sep 2006 Posts: 62 Location: Beaumont AB Canada

I bought this NEC about 6 months ago knowing it needed new tubes. It only has a little over 1500 hours on the meter but someone apparently left a static display on for an extended period and now it has some company's logo burned in. In any event I just got my new P16 tubes from Terry (great job of packing) and now it appears the red C element has what appears to be a bubble on the surface, almost like it melted.
Any idea what might have caused this and further does anyone have one they'd like to part with? Is this a hassle to change out?

Thanks

Mark_A_W · Posted: Wed Apr 28, 2010 1:55 am Post subject:

Hard to tell from that photo.

But typically, a burn in a C-element is caused by the sun. A projector with lenses fitted, is left in the sun..well...ever burn ants with a magnifying glass? Same deal.

An LC projector MUST have the lenses covered outdoors.

I'm afraid you need a new red C element. Good luck.

**Curt Palme** · Posted: Wed Apr 28, 2010 2:39 am Post subject:

I can't help with a red element, sorry, but have a clear here if you want it in the meantime..

Sparky015 · Posted: Wed Apr 28, 2010 4:32 pm Post subject:

You may be able to save that C-element. 3M still sells their precision optics coatings as part of their 3M Novec line. You may be able to score some and repair it if that's indeed what bubbled. Call 3M up and ask for a sample of the stuff.

Bill in Beaumont · Joined: 28 Sep 2006 Posts: 62 Location: Beaumont AB Canada

Bill in Beaumont · Joined: 28 Sep 2006 Posts: 62 Location: Beaumont AB Canada

**Curt Palme** · Posted: Thu Apr 29, 2010 12:53 am Post subject:

No, you can't, as the edges of the C element have way more coolant, so the tinting will be uneven. you'll lose the slightly darker reds that the C element gives, but it will work fine. I'll keep an eye out for a red C element for you, but right now I have nothing.

Mark_A_W · Posted: Thu Apr 29, 2010 4:12 am Post subject:

**Curt Palme** · Posted: Thu Apr 29, 2010 12:34 pm Post subject:

If you're running 16:9 or 2:35 only, you might be able to rotate the bubble outside of the viewing area. You'd have to peel off the black tape/paper top and bottom, but that bubble looks like it might be able to be rotated into phosphor area that isn't being used.

Take the tube out, take off the 4 screws holding the metal ring over the element, pull out the element, rotate and put plate and screws back on.

Sparky015 · Posted: Thu Apr 29, 2010 12:52 pm Post subject:

Have you seen if the bubble even impacts the picture on screen? I would check that as well. It may be ugly, but it may not affect your pic at all. Not sure, but it seems so far any optic coating flaw I've seen on a lens has not had an impact, other than cosmetically. I just don't know about a C-element It just sucks, because a lens you can pop on and off. A C-element requires a dismount of the tube and glycol work. It's a PITA, but worth a check to save yourself $200, IMHO.

**Curt Palme** · Posted: Thu Apr 29, 2010 1:58 pm Post subject:

THat one will. He'll get a warp in the scan lines if nothing else, and it will look weird.

SweetChuck · Posted: Thu Apr 29, 2010 3:12 pm Post subject:

I had the same thing happen on a 1351 , when moving house all 3 lenses faced the sunset for one afternoon . It was an expensive mistake . IMHO you have no choice but to change the C element

Bill in Beaumont · Joined: 28 Sep 2006 Posts: 62 Location: Beaumont AB Canada

Thanks guys for all your responses and ideas - here's a few comments -

Yes the flaw does show up on the screen when the PJ is fired up.
No I don't think rotating the C element is an option as the flaw is too close to the center.
No I didn't leave this in the sun - it was apparently like this when I bought it. I knew the tubes were an issue but not about the C element. Live and learn as they say........

Curt - I'll send you a PM to get a price on the part you have.

Sparky015 · Posted: Fri Apr 30, 2010 12:47 am Post subject:

I still say you should make an attempt at repairing it. If it's shot, you have nothing to lose. Good luck. If Curt doesn't have any clear C-elements, I have two.

Mark_A_W · Posted: Fri Apr 30, 2010 1:36 am Post subject:

You have two clear XG LC/G70 8" C elements for HD-18s?

They are much smaller than HD-10 C elements, and bigger than Barco retro 8" ones.

Sparky015 · Posted: Fri Apr 30, 2010 2:17 am Post subject:

Oops!

thought it was a HD-10 c. Don't have any of those.