摘要 |
The punch card is designed to provide a readable hole that is offset from, but intersects the window area of the reader. The punch hole plug is preformed by a pair of arcuate cuts held together by tabs at opposite sides. A small pilot hole at the center of the plug receives the narrow shank of a stylus. A shoulder above the stylus shank engages about the pilot hole and pushes the plug into a recess, tearing the two tabs away. The pilot hole is offset from the read window.
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