Term used for an ATV scheme that allows existing NTSC television sets to tune into the ATV signal and get pictures and sounds; also used to describe an MIT ATV scheme using blanking adjustment for aspect ratio accommodation and using various sub-channels to carry additional information but requiring a very complex receiver to recover that information. It is said to offer 600 lines of vertical and 660 lines of horizontal static luminance resolution, with reduced static diagonal resolution and with dynamic resolution comparable to NTSC. The term Receiver Compatibility, as it is usually used, allows some degradation in pictures from the highest NTSC quality, in the same way that the receiver-compatible NTSC colour system introduced cross-luminance to existing black-and white TV sets.