Glossary

 

Gray Scale

Test pattern of black-to-white gradation bars. The more levels

 

of gray scale that can be handled, the more realistic an image

 

can be displayed, especially a photograph that has been

 

scanned into the computer.

HDTV

(High Definition Television) Has approximately twice the

 

horizontal and vertical emitted resolution of standard NTSC.

 

HDTV systems are wide aspect ratio systems.

Hertz (Hz)

The standard unit of frequency. One Hz is equal to one cycle

 

per second. A Kilohertz (KHz) is 1,000 cycles per second and

 

a Megahertz (MHz) is equal to 1,000,000 cycles per second.

H-Grid

Test Pattern 8 with rows of white H's on screen, used as a

 

focusing aid.

Horizontal Scan

The rate at which horizontal lines are made to

Frequency (H-Freq)

scan on a CRT. This is controlled by horizontal sync from the

 

signal source.

Horizontal Scan

Reverses the image projection for front or rear

Reversal Jumper

projection. Located on the Horizontal Deflection Board.

Hue

Also referred to as tint. A specific color such a blue, pink or

 

aqua. Hue or tint control on a display device adjusts red/green

 

balance.

IDTV

(Improved Definition Television) Improvements that modify

 

NTSC standards. Improvements may be at the source or the

 

receiver.

Image Light Amplifier

A device that uses low-intensity images to phase-modulate a

ILA®

high-intensity light through a liquid crystal layer. It is the key

 

component in producing very bright, high resolution images

 

from Hughes-JVClarge-screen projectors.

Import Channel

Imports setup data from computer to projector. Store setup

 

data in computer and import during setup. Useful when

 

servicing the projector. See Export Channel Data and refer to

 

Appendix 1 for more details.

Infrared Repeater

Used with rear projection setups. Conveys infrared signals to

 

HJT Series 300 Projector, since I/R remote control signals

 

cannot reach I/R windows on the projector.

Model 330, 340SC, and 370SC Service Manual

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JVC 370 SC, 330, 340 SC service manual Hdtv