This project introduces a console application designed for functional and behavioral emulation of the old Soviet calculator EPOS-73 (ЭПОС-73) also known as Elektronika B3-11 (Электроника Б3-11). The project is conceived as an auxiliary for verification of the switch-level simulator based on Verilog HDL of the said apparatus. Calculator model EPOS-73 is interesting in that it was one of the first models of Soviet computing performed at LSI, that were fully designed by Soviet engineers. It was used a set of four LSIs series K1ZHG451...4 (К1ЖГ451...4) or later designation K145HK1...4 (К145ХК1...4). ...