CurtPalme.com Home Theater Forum

stefuel

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One for the living room and if that works well perhaps one hanging where the DaLite screen resides.

dturco

jask · Joined: 17 Mar 2006 Posts: 5468 Location: kamloops BC

more info?....

**Curt Palme** · Posted: Sun Nov 22, 2009 6:41 pm Post subject:

A scope is indeed handy to repair those LED units.

stefuel · Posted: Mon Nov 23, 2009 12:17 am Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 6970

The LED's are basically an LCD but using led lamps for backlighting instead of CCFL. They still use inverters for the lamps. Are you sure the power consumption is less? They do have 240hz scan rate and supposedly local dimming which allow certain areas to be dimming while other stay bright allowing for an enhanced black level.

Here's part of the guts from one:

**ecrabb** · Posted: Mon Nov 23, 2009 2:17 am Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 6970

This is from a factory training manual. I didn't show the whole page because I have to be careful of what I post. I haven't had my hands in one yet but have chatted with some that have. I'll see if I can get more info. The reason I question power consumption is because the basic functions between the two are almost the same. I'm curious if anyone has this data. The red circle and word inverter is in the manual. I didn't put it there.

macgyver655 · Joined: 22 Aug 2007 Posts: 6970

One suggestion I will give you Chip is, there are 2 types of LED backlighting. One is full panel lighting and the other is edge lighting. The edge lighting is only LED's around the outer edge with a diffusion panel to spread the light. The edge LED is not capable of local dimming where the full panel LED is. And as I said before, local dimming gives you better black levels which also gives you better color reproduction.

garyfritz · Joined: 08 Apr 2006 Posts: 7098 Location: Fort Collins, CO

I think I've been confused about "LED" flat-panel displays. I was thinking they were basically DLP back-projection sets that used pulsating LEDs instead of a lamp and a color wheel. (My brother has one of these, a Samsung model.) Certainly LEDs as a light source would be more efficient than the hot lamp. I think they are making LED projectors like this, but apparently most/all of them so far are just low-lumen portable projectors.

But apparently they're also making LCD displays that use LEDs for backlight instead of CCFL, and that's what you guys are talking about here?

dturco · Posted: Mon Nov 23, 2009 3:34 am Post subject:

I found this interesting. Slight explanation of LED technology.

http://www.nytimes.com/2009/06/18/technology/personaltech/18basics.html

donaldk · Joined: 17 Jun 2008 Posts: 267

Oh, you're not looking to get a LED panel, you're looking to get an LCD TV. Otherwise I would have suggested Mitsubishi and Barco. You'll still see screendoor though on the smallest LED spacing around, 4.5 mm. That new small prototype by Mitsubishi at the recent Ceatec show looked interesting aswell, ecept for its low lifeexpectancy.

stefuel · Posted: Mon Nov 23, 2009 10:31 am Post subject:

Yep, you do see screen door but only if you're close enough to get snot on the screen. I see scanlines from the same distance so what's the difference. I took a tape measure with me when I looked at the first one to see exactly what it would look like from the seated position. Even with glasses on, no SDE. The living room one is the test bed while I'm burning up the current set of tubes in the beastie. When those tubes are toast I'll be faced with the following options.

1. Re-tube a +30,000 hour set at a estimated cost of about $3,500.00 or replace the set with another CRT and that's not going to happen.
2. Put the $3,500.00 towards a JVC RS-2 or better which is a likely alternative. The lamps in the RS-2 are half the price of the Sharp LCD lamps I was buying in my first projector.
3. Switch to a LED flat panel, brand to be decided at that time.

Don't get me wrong. I love my AmPro. It's just getting a ton of hours on it and it's just a matter of time. I can see it all now. It will have 35,000 hours on it and things will start to go wrong on a regular basis. At that time I'll take a ragging from people like Pete who will say "See, I told you AmPro's were a piece of crap" Rolling Eyes

David_Web · Joined: 02 May 2007 Posts: 418 Location: Sweden

"Why would you say they still have an inverter, Mac? If a TV is LED-backlit, there shouldn't BE an inverter, because there's no fluorescent lamp..."

CCFL is DC to AC which means an inverter.

LED are DC to DC (or DC to current) which means an inverter.

"Oh, you're not looking to get a LED panel, you're looking to get an LCD TV."

True, that always bugged me when people get it wrong, can't blame them though as advertising makes it a LED panel.
One have to wonder if you should call the others CCFL panels then.

**ecrabb** · Posted: Mon Nov 23, 2009 4:27 pm Post subject:

Tom.W · Joined: 09 Mar 2006 Posts: 6368

Quote:

Don't get me wrong. I love my AmPro. It's just getting a ton of hours on it and it's just a matter of time. I can see it all now. It will have 35,000 hours on it and things will start to go wrong on a regular basis. At that time I'll take a ragging from people like Pete who will say "See, I told you AmPro's were a piece of crap" Rolling Eyes
_________________
Chip

Pete hasn't been around much so if you like I can carry on with his tradition...... Very Happy

macgyver655 · Joined: 22 Aug 2007 Posts: 6970

I am working on detailed info for you guys. I'm just waiting on some documents.

stefuel · Posted: Mon Nov 23, 2009 10:16 pm Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 6970

stefuel · Posted: Mon Nov 23, 2009 11:35 pm Post subject:

I thought there was something a southern muck. Laughing