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Stroke Circuits for CRT Display

IP.com Disclosure Number: IPCOM000092498D
Original Publication Date: 1966-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 31K

Publishing Venue

IBM

Related People

Boggs, BR: AUTHOR [+4]

Abstract

Characters are displayed on a CRT screen by selecting segments of a stroking raster R generated by a pair of digitally controlled operational amplifiers 10 and 11. The CRT beam is displaced by voltage taken Characters are displayed on a CRT screen by selecting segments of a stroking raster R generated by a pair of digitally controlled operational amplifiers 10 and 11. The CRT beam is displaced by voltage taken from output capacitors C12 and C17.

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Stroke Circuits for CRT Display

Characters are displayed on a CRT screen by selecting segments of a stroking raster R generated by a pair of digitally controlled operational amplifiers 10 and 11. The CRT beam is displaced by voltage taken Characters are displayed on a CRT screen by selecting segments of a stroking raster R generated by a pair of digitally controlled operational amplifiers 10 and 11. The CRT beam is displaced by voltage taken from output capacitors C12 and C17.

Amplifier 10 functions to control the voltage on C12 by providing selected charging and discharging paths through control of inputs 13, 14, and 16. Inputs 13 and 14 respectively permit fast and slow discharge of C12. Input 16 causes slow charge of C12 at a rate determined by resistor 21. Amplifier 11 performs similarly by selecting either fast or slow discharge of C17 through signals applied at inputs 18 and 19. Inputs 15 and 20 respectively provide the reset for amplifiers 10 and 11.

Sloping line R1 in raster R is generated by slow charge of C12 through resistor 21 combined with slow discharge of C17 through resistor 22. Sloping line R2 is generated by slow discharge of both C17 and C12 through resistors 22 and 23 respectively.

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