Backward compatible HDTV recording/reproducing system

A method for recording signals on a magnetic tape helically scanned during recording by a headwheel assembly including a first widetrack head followed in the forward direction of tape transportation by a first narrowtrack head on a first side of said headwheel assembly and including a second widetrack head followed in the forward direction of tape transportation by a second narrowtrack head on another side of said headwheel assembly rotated from said first side, said method comprising the steps of:

• applying a non-VHS recording signal to said first and second widetrack heads to create a contiguous set of uniform-width, relatively wide width parallel recording tracks diagonally crossing said magnetic tape;
• applying a VHS recording signal to said first and second narrowtrack heads for recording a respective set of uniform-width, relatively narrow width recording tracks over the central portion of each of said relatively wide width parallel recording tracks, thereby to leave a pair of tracks recording said non-VHS recording signal flanking each relatively narrow width recording track recording said VHS recording signal.

A magnetic recording medium having a recording format thereon of the type comprising:

• a plurality of a first type of parallel slant tracks recorded with a first information signal on the magnetic recording medium, said first type of tracks having a predetermined spacing therebetween, a given track width, and a given azimuth angle;
• and
• a plurality of a second type of slant tracks which are parallel to the slant tracks of said first type and recorded with non-return-to-zero modulation of a second information signal different from said first information signal on the magnetic recording medium, the width of the slant tracks of said second type being substantially one-half the predetermined spacing between the slant tracks of said first type so that two slant tracks of said second type are positioned between adjacent tracks of said first type, wherein said non-return-to-zero modulation of said second information signal conveys high-definition television information in compressed form, developed by discrete cosine transformation of said high-definition television information and by intra-frame and inter-frame compression of the resulting discrete cosine transforms.