receiver such as a portable telephone whereby electrocardiogram data and instruction information of conversation etc can be transferred between a patient and a doctor 2 configuration of relay transmitter receiver 19 and biological signal input apparatus pc in communication system in the embodiment the electrocardiogram data detected and recorded in the transmitter receiver 10 a of the biological signal detection apparatus is communicated with the remotely located biological signal input apparatus pc over the wide area network directly by the transmitter receiver 10 a or via the relay transmitter receiver 19 of a portable telephone etc not via the receiver 14 the recorder 16 or the transmitter receiver 17 as the holter electrocardiograph in the first embodiment whereby the electrocardiogram data and instruction information of conversation etc can be transferred between a patient and a doctor therefore in the embodiment the receiver 14 see fig4 the recorder 16 and the transmitter receiver 17 see fig5 as the holter electrocardiograph can be omitted in the embodiment the relay transmitter receiver 19 see fig6 and the biological signal input apparatus pc see fig7 described in the first embodiment can be used as they area with the relay transmitter receiver 19 see fig6 used in the second embodiment data or instruction information transferred to and from a transmitting and receiving section 73 via a transmitting and receiving antenna 72 is transferred to and from the transmitting and receiving antenna 47 of the transmitter receiver 10 a as the biological signal detection apparatus shown in fig1 likewise with the biological signal input apparatus pc see fig7 used in the embodiment data or instruction information transferred to and from a transmitting and receiving section 93 via.