Did I screw this PCB up?

CuteTurtle

CuteTurtle

CuteTurtle

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Joined
1 Oct 2011
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373
Hi,

Not sure where to post (or if I should even post on this forum) but my Samsung TV started clicking and eventually taking like 20 minutes to turn on. I opened it up and the capacitors were bubbly and leaking so I thought I'd have to replace them.

I bought a solder and all other tools. Having never soldered I thought I'd probably completely mess this up and I think I have. Replacement capacitors are coming tomorrow but I got the solder and etc today.

Judging from this picture, do you think I've pretty much messed up my chance at fixing my TV?

I know, It's a horrible solder job :( but the capacitor wires were so turned that it was difficult to get the lead underneath them no matter how hard I tried.

7AjXPF9.jpg


(I really appreciate any help!)
 
Hard to say from the image - most components will take 200-300C for upto 10 seconds (though less is better) but looks like there is a fair amount of heat scorching around the general area (unless its from the leakage) which potentially isn't good.
 
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They look quite clean, seen a lot worse, you do know you need to apply a good dob of solder to the actual connection/iron before you solder. Don't apply a raw solder iron to any connection or you will fry it.
 
jsmoke said:
They look quite clean, seen a lot worse, you do know you need to apply a good dob of solder to the actual connection/iron before you solder. Don't apply a raw solder iron to any connection or you will fry it.
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Didn't know that. I was just desoldering so I thought it wouldn't matter. At first I was using it raw with a pump but the pump was so horrible I bought some solder wick and used that with some flux paste. Thanks a lot for the rest of you because you're making me very hopeful again ! :-D
 
Personally I wouldn't have removed the old bits until I had the new ones to go on - One off, one on, smooth job.

The bottom right one looks like it might be a problem IMO. You won't know until you try.

Soldering is a horrible job! Not too shabby for your first attempt for sure.
 
BDEE said:
Personally I wouldn't have removed the old bits until I had the new ones to go on - One off, one on, smooth job.

The bottom right one looks like it might be a problem IMO. You won't know until you try.

Soldering is a horrible job! Not too shabby for your first attempt for sure.
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Yeah bottom right looks like the copper trace has been taken off, but it may just be the light.
 
Definitely not too shabby for a first try. Probably a bit too late now (assuming you didn't) but look up tinning the iron as its a good idea before first use and as above you always want to keep a bit of solder on the tip but don't go crazy and stick loads on just needs a small bit.

For through hole stuff you'll be fine but I find flux paste very useful for doing anything near SMD stuff and especially SMD components themselves as it makes it a lot easier not to accidentally bridge components - in this case though shouldn't be an issue.

Wick/braid >>>>> Pump x1000 though for de-soldering.
 
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Nothing screwed up as far as I can see, just some removed components. I'd have waited until I had the replacements though.
 
As someone with 30 years experience in electronics repair I would have to say, nope, that looks fine. The only thing that may have happened is stripping the copper via hole linings out, when soldering in the new parts make sure there is a joint on both sides of the board.
 
Conm8 said:
Looks alright OP. You going to give it a go?
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I will tomorrow! :-P

Thanks a lot for the helpful replies everyone. I did strip a little from the bottom one by accident because the wire just sort of got stuck there and no matter how many times I tried to get the lead out it wouldn't so I sort of pushed it out with pliers (well I was trying to position it up so I could take it out but that happened)

So I'll update this tomorrow to see if I blew up my house or got a working TV! :-D
 
Watch a few "how-to" soldering vids on youtube to see what a good joint looks like after soldering - you want a WigWam shape not an Igloo shape.
 
OK from what I can see the very bottom left pad has been damaged and looks like its been partially removed when you pulled the leaded device out. It looks like it should be connected to the large "track", this would appear to be the ground on the PCB and would require far more heat than the other pads as heat would dissipate throughout the PCB ground plane. Was the soldering iron used designed for use with lead free solder? or if was it just a see how hot it can go type? Lead free solder can require up to 30-40C more heat depending on the compound used, so some of the cheaper/older types of iron barely get hot enough to re-work lead-free items connected to gnd. I don't think it has done much damage to the board though, but make sure if the bottom left via hole is supposed to be connected to the ground plane that it is for both top and bottom of the via hole. For future you can use a heat gun with a small nozzle at a lowish speed, but fairly high temps. Add some flux and prior to this use your iron to add some solder to the pads you want to remove the device from. when the solder starts to melt with the heat gun the component can be removed, you can add some silver heat tape to help dissipate heat from the surrounding components on both sides of the board if possible before you start..
 
whats going to really bake your cookie is are you putting them in correctly, I hope you took pictures before removing them.
 
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