Tracking control circuit for maintaining substantial balance between reproduced signal levels from plural rotary magnetic heads when tracking control is applied in respect to only one of the heads

A magnetic recording and reproducing apparatus comprising:

• a rotary drum with a magnetic tape wound around said rotary drum and having a magnetic orientation in a direction substantially along the length of the tape;
• drive means for advancing said magnetic tape in said direction along the length of the tape in recording and reproducing modes of the apparatus;
• at least first and second magnetic heads mounted on said rotary drum and operative in recording and reproducing modes of the apparatus to record and reproduce high frequency information signals in successive first and second oblique tracks scanned by said first and second magnetic heads, respectively, as said magnetic tape is advanced in said direction along its length, with each of said first oblique tracks being next adjacent to at least one of said second oblique tracks and each of said oblique tracks extending at an angle .theta. with respect to said direction of magnetic orientation of the tape, and said first and second magnetic heads having mutually different azimuth angles for avoiding cross-talk in respect to said information signals recorded in said next adjacent first and second oblique tracks, said first magnetic head having a magnetic gap that is inclined with respect to said direction of magnetic orientation of said magnetic tape at an angle (.theta.+.alpha.) that is greater than said angle .theta. and said second magnetic head having a magnetic gap that is inclined with respect to said direction of magnetic orientation of said magnetic tape at an angle (.theta.-.beta.) that is less than said angle (.theta.+.alpha.), so that, in said reproducing mode of the apparatus, the level of information signals reproduced by said first magnetic head from said first oblique tracks scanned thereby is lower than the level of information signals reproduced by said second magnetic head from said second oblique tracks scanned by said second head by reason of the difference between said angles (.theta.+.alpha.) and (.theta.-.beta.), respectively;
• means operative in said recording mode for generating predetermined low frequency tracking control signals and for supplying said tracking control signals only to said second magnetic head for recording by the latter only in said second oblique tracks;
• means connected only with said first magnetic head in said reproducing mode and being then operative for detecting reproduction by said first magnetic head, in scanning one of said first oblique tracks, of said tracking control signals as cross-talk from each of said second oblique tracks which is next adjacent said one of the first oblique tracks;
• and
• scanning control means operative in said reproducing mode on said drive means for controlling only scanning by said first magnetic head in respect to said first oblique tracks by varying the speed of advancement of said magnetic tape in response to said tracking control signals reproduced as cross-talk only by said first magnetic head.