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Author Topic: Fragged  (Read 40 times)

Bomb Bloke

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Fragged
« on: May 22, 2010, 10:53:00 PM »

If all you've done is splash some solder about the place, you may be able to gently scrape it away with a soldering iron. Soldering wick (also known as soldering braid) is more suitable for the task.
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Zumodoki

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Fragged
« Reply #1 on: May 24, 2010, 06:44:00 PM »

One picture of one very badly done solder job

http://img269.images...9/s7301023g.jpg
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obcd

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Fragged
« Reply #2 on: May 25, 2010, 02:31:00 AM »

It looks like you have a piece of wire just above R7 R3 It doesn't look like it's shorting something, but it doesn't belong there.

It also looks like the trace running to pin 1 is broken. (It's a bit harder to see, so maybe it's just the picture.)

Did you install a pin header in those holes?

As long as your solderings aren't shorting some of the lpc pins together, they shouldn't really cause a frag, even if they are bad.

You need a clean unoxidated tip on your solder iron to do decent soldering work. Most low cost soldering irons have problems to produce a stable heat. Due to that, the tip starts to oxidate real fast. If you hit the iron tip with your solder, it should melt directly. This proves that there is no thermal barrier between the tip and the solder(Like oxidation of the tip.). To use desolder wick, you need a decent iron of minimum 30 - 40W. The cupper wires of the desolder wick absorb a lot of heat. Due to that, it's possible that the tip temperature of your iron comes below the melting temperature of the solder. If it doesn't melt, it can't be sucked up by the desolder wick.

The rebuild pcb just makes connections between the lpc points and other pcb points. You can use small wires to make those connections as well.
First, you will need to get your mobo going again without modchip.  

If you don't see any shorts in your soldering work, look for damaged pcb traces. Just scratching over them with your solder iron tip is usually enough to cut them. Use a magnifying glass to carefully examine them, or even better, use a ohm meter to see if both points of a pcb trace are still connected.

Trying to desolder a previous installed pin header usually makes things worse. So, unless you notice a short, don't start to experiment with desoldering wick.

regards.
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Zumodoki

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« Reply #3 on: May 25, 2010, 02:49:00 AM »

There shouldn't be any wire just solder, So must just be the picture, as you can see near the empty holes some marks, As I said bad job the iron was slipping sometimes too, I tried de-solder wick which wasnt doing the job, I was having trouble just getting the old solder to melt, After I installed the thing (Forgot the name black thing with pins that joins the mod chip to the board,

If I can remove this and its still fragged installing the pcb may fix it would it not, as that bypasses the standard connections no?

Also R7R3, Looking at the picture I see what you mean, I have no idea what that is, I need to dig the board back out later on today,

Im hoping to fix it, Cash flow is tight, Cant afford to replace the board currently

Also it would be nice to know that the first "Project" that i've bothered to try, isn't completely buggered! smile.gif
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obcd

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« Reply #4 on: May 28, 2010, 02:18:00 AM »

QUOTE
as you can see near the empty holes some marks

The marks shouldn't be a problem. If your solder iron tip slides over a pcb trace, it can cut that trace. (Which is probably what happend with the trace going to hole one (the square one top row left side))
QUOTE
the iron was slipping sometimes too

Which is because you have to add a lot of pressure on it, due to it's power being to low or it's tip being oxidated so that the heat transfer is bad. Also make sure you use the correct solder for electronic work. The solder should melt as soon as you touch it with the tip of your solder iron. The moment you need to add pressure, there is something not right. Sometimes, on very old pcb's, the solderings can be oxidated, so you need to add a little pressure. Usually, adding a bit of fresh solder to that soldering solves this.
QUOTE
After I installed the thing (Forgot the name black thing with pins that joins the mod chip to the board,

That thing is called a pin header. Trying to desolder it again will very likely make things worse. It's 10 times harder to desolder one than to solder one in.
QUOTE
I tried de-solder wick which wasnt doing the job, I was having trouble just getting the old solder to melt

I already explained the possible causes of that. The cupper wires in desolder wick can oxidate as well. I always cut off the first piece of it. If I have used it to remove some solder, I cut the first piece which already contains some solder so that I have some fresh new flexible cupper string. Make sure your solder iron is at least 30 - 40W to use desolder wick. A 15W iron won't do the job. Practice a bit on an old pcb of a piece of junk before you experiment with the xbox motherboard. Your local electronic store will probably have some defective clock radios or vcrs that contain pcbs to experiment. If you never soldered before, ask him to show you how soldering should be done, or try to find some instructive video's on youtube.
QUOTE

the pcb may fix it would it not, as that bypasses the standard connections no?

To rudely say it, in your dreams maybe, but in reallity no. The rework pcb for 1.5 and 1.6 xboxes only connects some points on the mobo to the lpc holes. Those connections are needed for the modchip and were  there on the older xbox versions. Microsoft removed them in an attempt to make modchip installs more difficult.
Your frag is probly caused by a pcb trace that got damaged. One that easily gets damaged is the D0 point, as that one isn't really designed to connect wires. Specially the top layer D0 point is a so called "via". It's actually a very small cilinder that is used to connect pcb traces from the top of the pcb to the bottom, and to the layers in between them. If you heat that one to long, it might stick on your solder iron tip. The bottom point D0 is a bit bigger, but I have seen cases where it was totally gone, together with a few inches of the pcb trace running to it. Reconnecting both ends of that trace with a small wire fixed the frag in that case.

regards.  
 
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