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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: sweetlilmre on September 20, 2007, 07:31:09 PM
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Hi,
I just installed my new (recently received) Blizzard PPC card, and it seemed to be behaving strangely. I took it out to make sure that the heatsink was seated properly, and that is when I noticed a small component (a capacitor?) was angled strangely.
Further inspection revealed that one leg was completely detached from the board. The components is marked: J106 it is a small black rectangular component with a white stripe on one side (I'm assuming a polarity marker).
I took a (bad, can't find my real camera) picture of where about the component was: http://img211.imageshack.us/my.php?image=image011wr9.jpg
and marked it with a red circle (bottom, middle of the pic).
I'd appreciate if someone could identify this for me, possibly providing a picture of a board with the component attached (so I can determine polarity when I find a replacement).
Thanks in advance
-(e)
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Yea, that is a surface mount component, most likely a capacitor or a resister. If one of the sides is lifted and no longer making a connection, then you will want to solder it back on.
Be forewarned these are very complex boards packed in a small area. You need a low wattage (around 30 watt or less) soldering iron, preferably a magnifying glass, a tool to hold the component in place while you solder (else it'l just stick to the solder iron and come right off), and most of all patience.
I could easily fix that particular component, but if there are traces that are bad too it's pretty much hopeless.
Thanks,
Neofree
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Hi,
The traces are fine, in fact the problem is that the legs of the component have sheared at the case, leaving almost nothing to solder to (one side is particularly bad). Hence looking for a replacement :( I suppose I could dremel the bad side extremely carefully to expose more of the leg, or will that destroy it?
I need to know what it is at this point. I need to find my camera! There are many other identical components on the board, which would probably help identify it.
I have a digital, temperature controlled soldering station and light / magnifying rig. What temperature would you recommend for SMT work?
Thanks
-(e)
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There should be identical ones, yeah. There's someone on these boards that could tell u what the component is so you can replace it. If you bezelled directly into the contact portion it might work but seriously.. You'd probably do better at attempting brain surgery without training... The connection Inside the component is probably incredibly small and u'd just drill right through it... Much better to replace the component. It's probably worth about 3 cents..
Thanks,
Neofree
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It's for a capacitor but I don't know the value.
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From your very blurry photo, it's a decoupling capacitor you have there.
U can put a 100nF (100 nanofarad = .1 microfarad) on place. Just rib the track with a scalpel very carefully to expose some copper to solder a replacement.
I suggest you to use no more than 280~300 Celsius degrees.
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Hi,
Thanks for the info! I will post a better picture, plus a pic of an identical component on the board (Found the camera! see below).
Also thanks for the temperature info. I'm quite good at soldering, but crap at electronic theory! :lol:
Luckily I don't need to scrape any traces as the legs are still attached to the board so the replacement soldering will be easy. I still need to determine the placement of the cap. (polarity).
EDIT:
Pic of identical component:
http://img525.imageshack.us/my.php?image=img0502lu4.jpg
Pic of where it broke off:
http://img525.imageshack.us/my.php?image=img0503is5.jpg
Pic of the entire board:
http://img525.imageshack.us/my.php?image=img0505iv8.jpg
-(e)
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The component is a tantalum capacitor.
It should probably go with the white stripe to the left. Why? because thats the way the rest of them are. It is good practice to orientate all all polarised components the same way. This is too make inspection easier.
The value 106 is the capacitance in picofarads (pF) where the last digit is the number of following zeros.
ie. 10 with 6 zeros. 10,000,000 pF or 10,000 nF or 10 uF
From the picture it looks like the cap was intended to decouple the not fitted IC. However I don't know what's on the other side. Either way it is extreamly unlikely that replacing this part will fix any problem this card may have.
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Hi,
Thanks for the excellent information. I am off to the local electronics store to get a replacement!
-(e)
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Hi,
in the worst cas, AmigaCenter can do it ! ;-)
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Hi,
Thanks to all of you I have made the repair which seems to work, or at least doesn't seem to be any worse.
I found out what the problem with the blizzard was (or at least a way to make it go away). Turns out that the card is picky about which bank the ram (128Mb module) is installed in. In desperation I switched the ram to the other bank and suddenly everything started working!!!
Previously I was getting a flashing red screen of death.
YAY! :-D :-D :-D
Thanks once again for the assistance, muchly appreciated!
-(e)