焊接問題

如果我想檢查一粒電阻, 或者電容, 有冇虛焊/焊得好唔好的話, 可以點CHECK?

基本用眼睇

BGA soldering use IR and X-Ray to detect.

這裡
http://wenku.baidu.com/view/7d83 ... ight=10&count=5

我N年前學銲嘢阿sir咁教，跟大家分享一下：

- 用1000grit沙紙fine sand下的電容電阻腳
- 以前的鍍金底板都會生銹！要用擦膠擦下至銲！而家鍍金底板應該好好，不過都建議清潔一下至銲！現今應該有清潔液，請各C兄介紹一下邊隻好用
- low resistance check: （唔多識點用中文寫，見諒）Multimeters have a continuity setting that probe for low resistances (short circuit). The symbol for a continuity test is usually a diode with dot emitting sound, indicating that if the meter detects short circuit, it will play a tone. Probe the 2 components after soldering and you should hear the dot sound waves.

多問一句底板還是搭棚

For low resistance check, 搭棚的零件腳容易probe到.底板如果真係probe唔到其中一隻的零件腳會試搵其他connecting point...所以幾時都應該清潔下的零件及底板增加bonding效果。