FIELD: instrumentation engineering. SUBSTANCE: binary signals of input-data sequence are distributed among code groups and the latter, among blocks; data swings in two record signal layers and time spaces between swings are shaped in compliance with code groups and their values; marker swings are shaped; second marker swings and spaces are disposed in record signals of blocks. Shaped sequences of marker and data spaces and swings for two layers of record signals of blocks are entered in medium. Additional data bits are shaped and added to code groups whose values are not lower than preset minimal permissible value. Their number and value for each group are set depending on code group value. Triple record-signal swings in two layers and sub- spaces between these swings whose length depends on values of respective additional data bits are shaped inside spaces corresponding to mentioned code groups. EFFECT: enhanced density characteristics in packing digital data in record signals of code groups. 1 cl, 2 dwg, 1 tbl
