Importance of research on specific aspects of ultrashort pulse propagation and voltage peak values localization along printed circuit board (PCB) multiconductor bus is highlighted. Simulation of a trapezoidal ultrashort pulse propagating along the conductors of the spacecraft autonomous navigation system bus with a different number of excited conductors and a variation of the whole ultrashort pulse duration (3; 0.3; 0.03 ns) has been carried out. In the case of 2 excited conductors, the crosstalk maximum value is 29% of steady state level of 0.5 V and the greatest (by modulus) minimum value is 33.4% of 0.5 V. In the case of 4 excited conductors, the maximum values are located in the nodes but the greatest minimum value is 39.8% of 0.5 V. It is shown that significant signal excess is observed with decreasing of ultrashort pulse duration both for maximum and minimum, but they appear in one transmission line section of the PCB bus.