dell w2600 power issues

[cadillacman]

Picked this up tonight. WIll be pulling it apart tonight. FOrmer owner says the tv has become fussy, sometimes will not power on. Once attemped to power on several times sometimes it will power on. Once on, it stays on..

I suspect caps or something but will see tonight. SO far ive been running it tonight and its been happy.. The guy said this was a 46" LOL NOT!!

[cadillacman]

Re: dell w2600 power issues

***OOPS THIS IS A W2700 ****

Ok this ones fixed. I wish they were all this easy. I powered it on, and after pulling covers of course started gently wiggling connectors. When i touched the connector for the "power cable" that goes from the power supply to the mainboard, the tv shut down. I pulled the ps. TONS of cold cracked solder joints. Most prevelant at the header pins for the connectors(all of them) but also found cold solder joints at the transformer joints, as well as other random places. Reflowed it all and so far its happy. Try as i might, i cant get it to break now so im pretty sure i got it.

heres some pics. black spots are permnant marker, so in the last pic with everything reflowed you can see where most of the bad joints were.. I should also note that i used some old cap lead and bridged the header pins togther wherver they shared a common trace. THis helps improve durability, they are less likely to develop cold solder joints again in the future.

[cadillacman]

Re: dell w2600 power issues

THis has been my personal tv since repairs.. Still going strong. My 2 year old son powers it on and down at least 20 times a day lol so im also getting some power cycles in.. Im calling this good. I wish they were all this ez to fix.

[momaka]

Re: dell w2600 power issues

Congrats on the fix!

All of the Lite-ON power supplies I've worked on or opened have always used lead-free solder and the soldering never looked good. Even their early power supplies from the Pentium-II days seem to use lead-free solder.
Probably explains the cold solder joints you got.

[golemmaster]

Re: dell w2600 power issues

The innerds looks exactly like a W2600 that I'd like to get working again. I wonder if the boards would work on a W2600 display.

[PowerAmpFreak]

Re: dell w2600 power issues

Congrats on the fix!

All of the Lite-ON power supplies I've worked on or opened have always used lead-free solder and the soldering never looked good. Even their early power supplies from the Pentium-II days seem to use lead-free solder.
Probably explains the cold solder joints you got.

I would not really say lead free solder is the same as getting low quality joints. We have used lead free from when the regulations told us to and if the soldering profiles are followed, which generally means you'll had to boost the temperature somewhat during the soldering process, you'll get high quality joints, just like the good old days with lead.
So I believe the crappy quality in the Lite-ON psu's is more or less the result of other factors in the process, but doing good lead-free soldering work is harder than with lead, that's for sure.

[PCBONEZ]

Re: dell w2600 power issues

Lead Free + Wave Soldering = Poor Joints a lot more often than with Leaded solder.
.

[PowerAmpFreak]

Re: dell w2600 power issues

Lead Free + Wave Soldering = Poor Joints a lot more often than with Leaded solder.
.

Yes, since it's harder to succeed with lead free soldering and it demands you know what you're doing in the process. Leaded solder is far more forgiving.
Wavesoldering leadfree requires the soldering and temperature profiles to be very precisely worked out, but in our own process of several thousands of different boards every year we still cannot see the quality of the solder joints to be of less quality than our leaded boards.
We were a bit worried about this in the start, but after several years of lead free production, dual, four and six layer boards, everything has turned out well.

[PCBONEZ]

Re: dell w2600 power issues

You didn't build those.
Some Chinese girl did.
Presumably at a higher volume.

[PowerAmpFreak]

Re: dell w2600 power issues

You didn't build those.
Some Chinese girl did.
Presumably at a higher volume.

No, I did not, so ...
Well, then

[dakers1]

Re: dell w2600 power issues

SEN ALAGIC Repairs the boards or at least did some time ago had 2 done still working in both TV's plasmatech@gmail.com