The ribbon cables in PB1400s and earlier PBs (at least), and the ribbon cables of PB displays, trackballs/trackpads and so on all operate in the same way. The tinned terminals on the ribbon cable contact their corresponding terminals inside the receptacle with room to spare. Firm contact is achieved by a connector-wide wedge-piece that is pushed home firmly after insertion of the cable end. To release a cable needs that you carefully, with either a (very) narrow-bladed screwdriver (jewellers, or equivalent), or preferably with the likes of an IC puller, raise the wedge to loosen the cable in the receptacle. The distance concerned is not more than a millimetre or so. This you do by using the narrow shoulders of the wedge, which protrude over the ends of the receptacle just far enough to be gripped and be useful. Too much force and you break the receptacle, so easy does it. The receptacle is more fragile than the ribbon cable, which is easily removed or inserted when the wedge is raised. When the receptacle is mounted on the MLB, breaking it writes off the whole MLB, because there is no effective repair for one other than by gluing cable and receptacle together with non-conductive silicone cement and the remnants of the wedge.

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