Follow-up to my original post here:http://www.avsforum.com/avs-vb/showt...5#post16971585
After a day's delay because of a backlog on red LEDs, the repairs commenced. It took about 3 hours, with some time spent exploring the TV's internals, but it was completed. The tomatoes are no longer blue. Here are some cautions, tips, and pictures that could be useful.
1. It helps to be have prior experience with, say PC building or repair. It can be daunting to stare at the various connectors, cables, and what-not otherwise. And as anyone who's dived into a PC knows: There Will Be Dust!
2. The manual (on a CD) is not a cookbook. It appears to be set up to aid with some interactive technician training, meaning the technician already knows what he or she needs to do. There are only general steps and pictures, but the level of detail is not impressive. It's also not obviously sequential. Each step seems to be tailored to a specific goal, like changing out a DMD board, but it's not straightforward on what the preceding steps should be.
3. BIG CAUTION: The replacement LED may not have thermal compound backing - mine did not. The original one does - a gooey gray paste that is squeezed between the LED's back side and the copper heat pipe and finned heat sink. PC builders use this stuff to help heat conduction between a PC's CPU and its heat sink. I happened to have a tube of Arctic Silver handy. For PC builders, it's recommended that only a thin layer of compound should be used - I'm going by that practice. It bothered me a little to see how thick the compound was layered on the original heat sink.So there's is a BIG RISK here if you do not have thermal compound
(or in my case, if Arctic Silver is not appropriate to use; I'm keeping fingers and toes crossed).
4. Be mindful of what connectors you're removing, and of the internal cable routing - there are more than a few interferences and chances to snag wires.
5. There are some fan covers that make you wonder, what the heck are these for? They seem like afterthoughts, but I think they do assist in directing what airflow is available.
6. Finger-tight is just fine. No need to over-torque, big guy.
1. Take (digital) pictures before each step. This will help you remember what the area looked like before you demolished it.
2. The CD from partstore.com was unlabelled, and the manual was a series of PDFs. If you don't want to print a lot of pages to get the color pics, load the CD onto a laptop, and view from there.
3. Tools needed:
a. Philips head screwdriver - preferably magnetic tip, to avoid losing screws.
b. Can of air - to blow out dust concentrations on fan tips, heat sink, etc. Do keep dust away from the obvious optics.
c. Thermal compound (see previous).
d. An old hotel key card, to scrape off the old thermal compound from the heat sink contact surface, and some isopropyl (rubbing alcohol) to clean the surface.
e. Your brain - maintain a presence of mind to group screws removed, and orientation of various covers.
4. Finally, DON'T PANIC. Panic will have you dropping screws, acting hastily, and next thing you know, something breaks.
Here's the Flickr stream of pics, presented in general sequence. The pictures have some notes. My wife told me I took too many pictures of elk in Yellowstone. Thus, I'm being judicious about what to present...http://www.flickr.com/photos/4146111...7621917760677/
Anyway, let me know if the link doesn't work, or other suggestions to improve this post.
FINAL THOUGHTS... For Now.
I think I can see why the red LED went out first. It's furthest away from the main heat sink bay, and even though it had its own dedicated, but small (~50? mm), fan, there's a limited air exchange that probably leads to heat buildup. In general, all the fans sound like they run at low RPM, to minimize noise. In my opinion, in its original state, this design does not lend itself to longevity, despite the advertised long life of the LED engine. The case stands to have a few more ventilation openings. There's a mod in this TV's future.
Until the next repair!