PWB samples were subjected to the solder float test per MIL-P-55110 and then the PTHs were cross-sectioned.
印制板试样必须经过MIL—P—55110标准浮焊试验，然后对金属化孔进行剖视。
2
The duration radio of each is influenced neither by English nor Chinese diphthongs. The duration pattern of each English diphthong produced by PTHS shows a unique characteristic.