Display Terminal to TV Monitor Adapter
Original Publication Date: 1984-Aug-01
Included in the Prior Art Database: 2005-Feb-04
Shown in the figure is an adapter circuit that permits the contents of the screen of a workstation, and more particularly that of an IBM 6580 display terminal, to be displayed on one or more TV monitors. The horizontal and vertical synchronization pulses, Synchro H and Synchro V, from the display terminal are respectively applied to single-shots SS1 and SS2 which convert them into pulses that are compatible to TV standards. Typically, to be in compliance with United States TV standards the widths of the output pulses from SS1 and SS2 are 4.6 and 180 microseconds, respectively. The output signals from SS1 and SS2 are combined by a set of four NAND gates 10-13 to provide a TV composite synchronization signal which is applied to the base of transistor Q1.