optimal threshold value then the control part 20 sets the obtained optimal threshold value in the threshold value adjusting part 41 as the final reception threshold value thereafter the control part 20 switches the changeover switches 46 and 47 of the clock extraction part 40 to set the operation mode to the active mode accordingly the circuit 200 of the device 1 can receive the reception signal from the data transmission and reception module 100 with the influence of the crosstalk from the transmission part 30 on the reception part 10 minimized fig3 is the first conceptual diagram illustrating the influence of the crosstalk from the transmission part on the reception part the diagram illustrates a transmission signal 71 a crosstalk signal 72 attributed to the transmission signal 71 and a reception signal 73 deteriorated by the crosstalk signal 72 with the signals associated with one another on the same time axis in the example illustrated herein rise and fall timing 51 of the transmission signal 71 coincides with bit determination timing 52 of the reception signal 73 for the convenience of explanation the present example illustrates a signal pattern in which the amplitude of the transmission signal 71 and the reception signal 73 repeats the on off cycle for every 1 bit pulse generally the magnitude of the crosstalk attributed to the transmission signal 71 tends to be maximized at the rise and.