what is underlying modulation scheme using on video digita..

Archived from groups: rec.video.desktop (More info?)

Does someone have a pointer to a good description of what the
recording/signalling process that is used when making a digital
recording onto the typical hellical video tape. I'm sure that its a
lot more complicated than simple 1's and 0's recorded more like some
kind of quadrature modulated ac signal that has the bits encoded in a
sub carrier or something like that.

I'd just like to know what the underlying digital recording
technology that is used on these VDAT devices.

The bottom line is to understand why the mosaic noise appears on non-hi
8 tapes in Sony's 8 mm DAT camcorders and why its related to fast
changing scenes in the video immages. I assume that fast changing
scenes when ecoded into the 1st stage of DCT thats part of the DIV
standard translates to a higher frequency signal that is recorded onto
tape that is in turn is more subject to dropout and then the mosaic
distortion. No big deal. I just wanna know and I know enough to be
dangerous so I want to be a little more dangerous.

I also wonder if these 8mm Digital video tapes from camcorders can be
read by the now old and obsolete 8 mm VDATs that you may find in some
older computers. ie does the camcorder lay down a standard file
structure that a computer could read.

tks
Don