Abstract: A hand-operated tool for removing and replacing a wide variety of different manhole covers is disclosed. The tool includes a handle which extends upward from slip-resistant feet. A collar with forward extending ears attaches to the lower, central region of the handle. An S-hook is positioned within the ears so that its hook extends downward and frontward, and a clevis is positioned outside the ears. The S-hook, clevis, and ears are all bolted together. One end of a chain attaches to the clevis, and another end of the chain attaches to a link of an elongated link-up unit. The link-up unit's link is dimensioned for snug, but hand-removable, attachment to the S-hook. The snug attachment resists rotation between the link-up unit and the S-hook. A hook pivotably couples to the link-up unit at an opposing end from the link-up unit's link. The hook is coupled so that is can pivot up and down only, and cannot freely rotate around the general direction of elongation of the link-up unit.
Abstract: An automated classroom which integrates sources of video instructional materials, such as TV, CATV, VCR, video disk players, closed circuit TV, and the like, with sources of computer-based instructional materials is disclosed. Modulated video sources are converted to baseband and applied, along with baseband video sources, to a multichannel modulator or headend. The headend drives a local video network (LVN) which couples to a plurality of student workstations and to an instructor workstation. In addition a local area network (LAN) couples to the student workstations, the instructor workstation, and to a file server. Each of the instructor and student workstations includes a computer, a monitor control unit (MCU), a video display, and an audio transducer. The workstation computers couple to the LAN and the workstation MCU's couple to the LVN.