| 摘要 |
Disclosed is an improved printed circuit board having circuit patterns printed thereon. It has a plurality of composite lands each including a first land having a terminal hole made at its center for inserting the terminal of a selected electric or electronic part or device, and a plurality of second lands each being contiguous to and extending outwards from the first land. The areas contiguous to the contours of the first and second lands have no conductive foils such as copper foils to expose the substrate surface of the printed circuit board. The exposed areas are effective to confine the thermal energy in the limited areas for soldering. And the composite land shape defines a ridged cone like solder lump, which can fixedly grip the terminal of the part or device.
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