| 摘要 |
<p>The circuit board is in the form of a plate of dielectric material, in which the conducting paths are shaped as depressions in the surface of the board. The bases are given an adherent metal coating. Suitable holes are provided at points at which connections have to be made, which can be plated through. The board is produced by the preparation of suitably moulded boards with the necessary depressions pre-formed, which is then covered with a mask for the application of metallisation; to improve adherence the depressions may first be roughened by sandblasting of chemical treatment.</p> |
