Cassette recorder with switching for a device for noise suppression

A magnetic tape recorder having a means for actuating recording and a means for actuating playback of sounds as well as a noise suppression means, comprising

• switch means for selectively placing the noise suppression means in operation for direct reproduction of radio broadcasts,
• a sound carrier tape cassette having a magnetic tape therein and a rear wall formed with a selectively removable break-through tab in said wall, the presence of said break-through tab constituting an indicia of an absense of a recording being on the tape, and the absense of said break-through tab defining a break-through opening in said wall, constituting an indicia of a presence of a recording on the tape,
• sensor means for sensing said break-through opening and said break-through tab, respectively, of said cassette, when the latter is positioned in an operating position in the tape recorder,
• said sensor means including a first abutment surface on a front side thereof and a relatively rearwardly disposed second abutment surface, said sensor means and said first abutment surface thereof being formed with a recess defined in part by said second abutment surface, said second abutment surface being disposed behind and adjacent said first abutment surface with respect to a sensing movement direction of insertion of said cassette such that three different positions of said sensing means result, namely:
• a first position wherein said first abutment surface of said sensor means engages against said break-through tab, the latter constituting an unopened wall portion of said cassette;
• a second position wherein said tab is absent and another portion of said wall of said cassette adjacent said break-through
• opening of said cassette is inserted in said recess and with said second abutment surface on said sensor means abutting against said another portion of said wall of said cassette adjacent said break-through opening;
• a third position wherein said sensor means during an absence of said cassette is unabutted by any wall of said cassette;
• locking means for operatively blocking a movement of the means for actuating recording into an operating condition of the latter, said locking means being operatively connected with said sensor means,
• said sensor means for actuating said locking means to be operative for blocking said means for actuating recording when said sensor means is in said second position, and for making said locking means inoperative to block said means for actuating recording when said sensor means is in said first or third positions, respectively.