With a 75-percent red baseband signal, the modulated channel 4 signal is reproduced on the screen (above left). With a 100-percent signal, the screen turns mud-orange-green (above right).
The Setup:
A 75-percent red NTSC signal originating from a Digital Video Essentials DVD swamps CT-100 B8000194 when the baseband signal increases from 75 to 100 percent saturation. The same 100 percent red image is correctly displayed on a digital TV operating in NTSC mode.
An oscilloscope in the lower right hand corner of each picture displays the I signal on the top trace and the red G1 (control grid) signal on the lower trace.
These images were taken with daylight illuminating the room.