Method of adjusting magnetic head of magnetic tape recording and reproducing apparatus and magnetic tape recording and reproducing apparatus

A method of adjusting a recording head of a helical scan system magnetic tape recording and reproducing apparatus for recording and/or reproducing data on and/or from a magnetic tape by n recording heads and m reproducing heads mounted on a rotary drum comprising the steps of:

• a first process in which a plurality of tracks is formed on said magnetic tape by alternately supplying a measurement signal and an erasure signal to an i-th (i=1 to n) recording head of said n recording heads, a track formed by said i-th recording head is reproduced by a j-th (j=1 to m) reproducing head of said m reproducing heads, a variable Ri_optimum corresponding to a width of a track formed by said i-th recording head is obtained from a reproduced signal obtained by said reproduction and n variables Ri_optimum (i=1 to n) corresponding to the widths of said tracks are sequentially obtained from said plurality of tracks formed by each of said n recording heads by repeating the above-mentioned operations n times;
• a second process in which a plurality of tracks is formed on said magnetic tape by supplying a measurement signal to said n recording heads, a track formed by said i-th (i=1 to n) recording head of said n recording heads is reproduced by said j-th reproducing head, a variable Ri_now corresponding to a width of a track formed by said i-th recording head is obtained from a reproduced signal obtained by said reproduction and n variables Ri_now (i=1 to n) corresponding to said track widths are sequentially obtained from said plurality of tracks formed by each of said n recording heads by repeating the above-mentioned operations n times;
• and
• a third process in which said recording head is positioned such that deviation Δi, Δi=|Ri_optimum−Ri_now| (i=1 to n) obtained from said variable Ri_optimum of said i-th track width obtained from said first process and said variable Ri_now of said i-th track width obtained from said second process of said track formed by said i-th recording head becomes smaller than a desired value in all of said n recording heads.