The Fiber Optics Illustrated Dictionary - Part 106 fills a gap in the literature by providing instructors, hobbyists, and top-level engineers with an accessible, current reference. From the author of the best-selling Telecommunications Illustrated Dictionary, this comprehensive reference includes fundamental physics, basic technical information for fiber splicing, installation, maintenance, and repair, and follow-up information for communications and other professionals using fiber optic components. Well-balanced, well-researched, and extensively cross-referenced, it also includes hundreds of photographs, charts, and diagrams that clarify the more complex ideas and put simpler ideas into their applications context | Fiber Optics Illustrated Dictionary into sections or zones. Cables are centralized in each zone with main arteries running between zones or to the central power source. See distribution frame zone of authority The set of names managed by or under the authority of a specific name server. zone of silence skip zone In radio transmissions a geographic region that does not receive normal radio signals frequently due to abrupt changes in terrain . mountains . zone paging The capability of an intercom or phone system to selectively page certain groups of speakers. See public address system. zone punch In a punch card a punch located in one of the upper three rows the section that usually has less text displayed on the card . See Hollerith card punch card. Contrast with digit punch. zone time A system in which the Earth is divided longitudinally into 24 time zones of about 15 degrees each starting in Greenwich England. It was developed in the late 1800s by a Canadian s. Fleming to establish a standard time. See Greenwich Mean Time zoning stepping In microwave transmissions displacement of portions of the surface of the microwave reflector in order to prevent changes in the phase front in the near field. zoom To continuously reduce or enlarge an image as on a monitor or in a viewfinder. Zooming capability is usually provided to improve the visibility of details zoom in or to provide a big picture wide angle view zoom out of a diagram object image or scene. See zoom factor. zoom factor The degree to which an image can be scaled that is decreased or enlarged. The X and Y axes may or may not be capable of sizing independent of one another. The enlargement zoom factor on consumer camcorders often ranges from 20 to 200 times or more the normal viewing factor. In some cases the zoom factor on still cameras and camcorders may be digitally enhanced that is the zoom up to 20 times may be an optical zoom and beyond that it may be a digital zoom which may show some pixelation at .