Did I screw this PCB up?

^^ Picture seems to have orientation diagrams and + symbols for the caps on the PCB itself - backed up by what msmalls74 said - the left hand traces appear to be grounds.
 
one trick I use for desoldering from RoHS boards, is to first /add/ some solder, make sure you only use Pb solder tho.
The logic is that it will lower the melting temperature of the whole blob, making it a lot easier to use the pump (or wick). No-Pb solder melting point is like 50C more than the Pb kind, and nowhere near as runny.
 
The tip keeps going back instantly. I didn't tin the tip the first time so maybe I've screwed it up this way but now when I turned it on and tried to tin the tip it just goes black instantly. I even turned it off, managed to scrape some off the black stuff off and turned it back on but it just went black again as soon as I tried.

Do I really need to buy another solder just for this one job? (This is a cheap £10 one, won't lie)

I don't really want to spend £50 on a soldering iron I'll use once though.
 
How old is the TV? I'm wondering because there is an old thread on OcUK's board about, Samsung monitors failing because of capacitors and since then, Samsung have apparently started using different caps. Even my old, Sammy monitor failed on the caps and before I found that thread I took the monitor apart out of curiosity to see what they're like inside and mullered one of the ports. My old monitor is a SyncMaster 226bw which I bought in 2007 iirc and it died in 2013. It operated as a second display for about a year because it was behaving the same as your TV until it finally never came on.
 
CuteTurtle said:
The tip keeps going back instantly. I didn't tin the tip the first time so maybe I've screwed it up this way but now when I turned it on and tried to tin the tip it just goes black instantly. I even turned it off, managed to scrape some off the black stuff off and turned it back on but it just went black again as soon as I tried.

Do I really need to buy another solder just for this one job? (This is a cheap £10 one, won't lie)

I don't really want to spend £50 on a soldering iron I'll use once though.
Click to expand...

It's too hot, that's all. Quite frankly any soldering iron that isn't temperature controlled is like using a hacksaw to do brain surgery :-)
Try to get one of these metal ball of wire from tesco, and clean the tip with that. You don't want it /pristine/ just clean; and don't let it 'dry', make sure you turn the iron off when not in use...
 
H9PmAZD.jpg


This is sort of the best I could do. I know I should have aimed to make them more like ^ instead of blobs but it wouldn't work. I watched the video above how not to put the tip to the actual solder but apply it from the other side and let it melt nicely but that wasn't working (it wasn't melting). Good enough? Or should I re-try?
 
CuteTurtle said:
This is sort of the best I could do. I know I should have aimed to make them more like ^ instead of blobs but it wouldn't work.
Click to expand...

Not watched the vid, does it explain tinning? if not that's why it isn't working. Tin the soldering iron first by putting a bit of solder on it, then with the solder and iron either side of the capacitor leg bring the solder and iron together again keeping the leg in the middle, the solder should then wrap around the leg and leave a nice bubble when you pull away.
 
esoteric said:
Not watched the vid, does it explain tinning? if not that's why it isn't working. Tin the soldering iron first by putting a bit of solder on it, then with the solder and iron either side of the capacitor leg bring the solder and iron together again keeping the leg in the middle, the solder should then wrap around the leg and leave a nice bubble when you pull away.
Click to expand...

Ah, I'll keep this in mind next time. Btw, it ****ing works. I can't believe this didn't explode or something. I haven't felt this great about something I've fixed in a long time.
 
CuteTurtle said:
Ah, I'll keep this in mind next time. Btw, it ****ing works. I can't believe this didn't explode or something. I haven't felt this great about something I've fixed in a long time.
Click to expand...

I find soldering (when its not being super frustrating) quite rewarding and almost cathartic (not quite the right word but I can't think of something more appropriate).

Looks like you bent the leads in the image - while it makes it 100x easier to hold the component in place to apply the solder its generally considered to be best avoided as it makes it easier to accidentally bridge components/traces. (Though personally I bend them quite a bit of the time as sometimes its just not worth the aggro trying to keep the part in place otherwise).

The type (eutectic v non-eutectic solder, lead/non-lead, etc.) and quality of solder makes some odds when it comes to forming the solder joints but getting the shape mostly comes from leaving the iron applied for like 0.5 seconds longer than the solder so the heat draws it in. I've never really found the shape makes all that much odds through.
 
BTW I've been using Blue-Tak to hold components on one face when soldering the other. Magic :-)

As for the 'conic' shape of the join, what I do is heat the component and apply solder as usual, then I flick the soldering iron /up/ on the leg of the component itself instead of just pulling it away, so that 'draws' any extra solder 'up' and make a nice cone; any remaining will disappear when you clip the legs of.
 
Well

Seems like I might of screwed it up afterall.

It's been working perfectly for the last day however now I was on the computer and I heard a noise from the TV, it decided to turn on or something by itself. The brightness is really low now and the image is deformed. It's turning on/off by itself and the red light is going crazy.

Just when I thought it was perfect :-D!

ekYiJGt.jpg


(Looks a lot brighter than it really is on the picture, It's dark as ****!)

Edit: Setting the contrast to 0 helped, picture seems alright but so dark that it's annoying. Turning brightness up messes up the colors again.
 
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esoteric said:
How old is the TV? I'm wondering because there is an old thread on OcUK's board about, Samsung monitors failing because of capacitors and since then, Samsung have apparently started using different caps. Even my old, Sammy monitor failed on the caps and before I found that thread I took the monitor apart out of curiosity to see what they're like inside and mullered one of the ports. My old monitor is a SyncMaster 226bw which I bought in 2007 iirc and it died in 2013. It operated as a second display for about a year because it was behaving the same as your TV until it finally never came on.
Click to expand...

I replaced the capacitors in my old 226BW - had exactly the same fault. Been working good as new for about a year now. The old capacitors were CapXon and I replaced them all with Panasonics. Guide here with part numbers etc

I think they did go through a period of using really poor quality capacitors on the power boards so it wouldn't surprise me if the TVs fell foul of the same design choices.
 
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