PCM Tape recording and reproducing apparatus having a dropout-immune data recording format

A PCM tape recording and reproducing apparatus wherein an input analog signal is converted into digital data in serial form, said digital data being divided into frames, each frame containing a plurality of data words and an error detection word, and a given number of frames in series forming a group for error correction and being interleaved to be recorded on a plurality of tracks of a magnetic tape through multi-track heads in a matrix of columns and rows, said rows corresponding to the tape tracks, said digital data recorded on the magnetic tape being picked up through reproducing multi-track heads and thereafter being de-interleaved and converted into an analog signal to reproduce said input analog signal, said apparatus comprising:

• on the recording side,
• (a) track-selecting and frame-forming means for forming a series of input digital data composed of words having a prescribed number of bits into a series frames and for selecting a respective one of said plurality of tracks for receipt of each of the series frames in such a manner that adjacent ones of said series frames of the same group are located at least one track width apart from each other in the track width direction on said plurality of tracks of said magnetic tape;
• (b) means for delaying sets of consecutive ones of said series frames of the same group, as assigned to said respective tracks by respectively different amounts relative to the track-length direction so that different columns containing frames of the same group are at least one column apart from each other on the tape tracks and for recording respective series frames thus dispersely arranged on said tape;
• and
• on the reproducing side
• (c) means for rearranging data picked up in parallel from said tracks on said magnetic tape by de-interleaving so as to produce said series data frames.