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#Continued from 19539
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NTSC (composite) video signal is usually fed into the monitor with a
75-ohm cable and a plug that looks much like a stereo cable plug (RCA phono).
The color information is contained in this signal with a subcarrier (19 MHz
?) with the chrominance encoded by phase modulation of the subcarrier. The
luminance signal is on the main carrier. Sound is too. The bandwidth of this
mode is not nearly as high as either of the RGBs. The NTSC plug on the back
of the Amiga is this signal.
RGB stands for red, green, blue, not surprisingly. Analog RGB (Yea!) is a
series of three signals which address the intensities of each of the electron
guns in the color CRT to generate the full color gamut of the CRT. These
signals can be varied in intensity continuously, thus generating as many
distinct colors as the driving computer can spit out (Amiga = 4096). There
are other signals required on this cable to effect the vertical and
horizontal synchronization.
Digital RGB (sometimes called RGBI for RGB and Intensity) is a series of
three signals for the three CRT guns as above, but each line (R, G, or B) can
only have two states (TTL logic high and low). If one recalls one's
combinatorial analysis, that comes to eight different colors. The "I" signal
also has two states and can give each "hue" two levels of intensity yielding
what the IBM folks gratuitously refer to as SIXTEEN COLORS! There are really
only eight distinct hues. This is the color one gets on the relatively
standard PEE CEEs of various species. It's also the color on the C128 in the
128 mode. The alphanumerics are quite sharp with RGBI and the colors
rendered, albeit limited in number, are distinct.
I guess that's more than you wanted to know, but I get carried away on my
Amiga keyboard. I have the KV-1311CR and it is superb. There is some pincushion
distortion on the screen periphery, but it is slight. I would have preferred
the CPD-1201, but it wasn't available locally and I wanted something NOW! I got
one of the first Amigas in Portland (OR) and they weren't shipping monitors
then. When I use an Amiga now with the 1080 monitor, I notice the difference in
dot pitch and in CRT color gamut. The 1080 monitor is an excellent buy, but,
for additional money (here) the Sony does an excellent job.
Color subcarries is 3.579545 MHz.
Color subcarries is 3.579545 MHz.