Extron electronic 6400s - Manual (Page 64)

Reference Information, cont’d
Matrix 3200/6400 Series • Reference Information A-8
Frame – In interlaced video, a Frame is one complete picture. A Frame is made
up of two fields, or two sets of interlaced lines.
Frequency Range – Refers to the low-to-high limits of a device, such as a
computer, projector or monitor. Also “bandwidth”.
Gain – A general term used to denote an increase in signal power or voltage
produced by an amplifier in transmitting a signal from one point to another.
The amount of gain is usually expressed in decibels above a reference level.
Opposite of Attenuation.
Genlock – A method of synchronizing video equipment by using a common,
external “Genlock” signal.
Hertz – Hz – A measure of frequency in cycles per second.
High Impedance – Hi Z or High Z – In video, when the signal is not terminated
locally and is going to another destination, where it will be terminated. In
video, Hi Z is typically 10k ohms or greater.
Horizontal Rate – Horizontal Frequency – The number of complete horizontal
lines, including trace and retrace, scanned per second. Typically shown as a
measure of kHz.
Horizontal Resolution – Smallest increment of a television picture that can be
discerned in the horizontal plane. This increment is dependent upon the
video bandwidth and is measured in frequency. Determines the number of
lines it takes to scan an image on the screen.
Hue – Tint Control – Red, yellow, blue, etc. are hues of color or types of color.
Hue is the parameter of color that allows us to distinguish between colors.
Hz – Hertz – Frequency in cycles per second.
Impedance – Z – The opposition or “load” to a signal. Circuits that generate
audio or video signals, are designed to work with a certain “load”, or
impedance. Typical video impedances: 75 ohm or High Z. Also see High
Impedance and Low Impedance.
Interlaced – The process of scanning whereby the alternate lines of both
scanned fields fall evenly between each other.
IRE Scale – An oscilloscope scale that applies to composite video levels.
Typically there are 140 IRE units in one volt (1 IRE = 7.14 mV).
K – An abbreviation for kilobyte. A kilobyte is 1,000 bytes. In computer memory
sizes, the numbers are rounded down. e.g. 1k byte = 1024 bytes.
Kilohertz – kHz – Thousands of Hertz, or a frequency rate in units of thousands
of cycles per second. For example, CGA’s horizontal scan rate is 15.75 kHz
or 15,750 hertz (Hz).
LED – Light-Emitting Diode
Level Control – The Level Control on selected Extron interface products is
similar to the Contrast Control on a data monitor. It can either increase or
decrease the output voltage level of the interface to the connected data
monitor or projector. This results in greater or less contrast in the picture.
Low Impedance – The condition where the source or load is at a lower
impedance than the characteristic impedance of the cable. Low source
impedances are common; low load impedances are usually fault conditions.
Luminance – This is the signal that represents brightness in a video picture.
Luminance is any value between black and white. In mathematical
equations, luminance is abbreviated as “Y”.
M – Mega – An abbreviation for megabyte. A megabyte is 1024K, or roughly a
million bytes (1,048,076 to be exact [1024 x 1024]).
Matrix – In A/V, an electronic device used to collect and distribute video (and
sometimes audio) signals. See matrix switcher.