Abstract: Top-mount PCB mounting assemblies, and electronic devices and optical communication device thereof are provided. The top-mount PCB mounting assemblies may include a PCB with a top surface as a reference surface; a chassis disposed underneath the PCB and separate from the PCB; a shoulder screw comprising a screw head, a screw body and a screw tail, where the shoulder screw is soldered on a top of the PCB and is connected to the chassis by tightening a M2.5 screw from a bottom of the chassis; and a nut, positioned between the PCB and the chassis, made of a rigid feature, and configured to receive and fasten the shoulder screw and keep a distance between the PCB and the chassis within a controlled dimension.

Abstract: Methods, systems, and apparatus for optical communications. One of the apparatuses includes a spool comprising a spool wheel, one or more separate spool portions positioned on the spool wheel, and one or more bearings positioned on the spool wheel, wherein the one or more spool portions and the one or more bearings are configured such that an optical fiber ribbon can be wound through the spool; and a spring coupled to the spool wheel such that the spring provides a rotational force on the spool in a direction that winds the optical fiber ribbon.

Abstract: Methods, systems, and apparatus for optical communications. One of the apparatuses includes a spool comprising a spool wheel, one or more separate spool portions positioned on the spool wheel, and one or more bearings positioned on the spool wheel, wherein the one or more spool portions and the one or more bearings are configured such that an optical fiber ribbon can be wound through the spool; and a spring coupled to the spool wheel such that the spring provides a rotational force on the spool in a direction that winds the optical fiber ribbon.