peebee:
The formulas you shown for the Y/Pb/Pr are for the old NTSC/PAL standard (525/625). It does not match with HDTV (1080/720) standard. Here is the one for HD:
Y' = 0.2126R'+ 0.7152G'+ 0.0722B'
Pb = [(0.5/1-0.0722)]/(B'-Y')
Pr = [(0.5/1-0.2126)]/(R'-Y')
And, all three signals has...
You should not add the data by just modulate on the same carrier. The NTSC RF has two carriers: Video and Audio. The Video is AM and Audio uses FM. The video has bandwidth little more than 3 MHz and audio about 4.5 MHz +/- 250 KHz. Therefore, any straight modulation on the same RF frequency...