Multichannel telemetric system for biomedical signals via switched telephone lines

THE PROBLEM of the transmission of biomedical signals by telephone lines has already received, in past years, the attention of several research workers and industrial organisations and, at present, no doubl exists of the utility of such aids in medical field. This fact is also confirmed by the existence of international committees and particular rules for such transmission systems (see references). With reference to the activity of 'the I.E.I.-C.N.R. of Pisa in biomedical telemetry via switched telephone lines, in this note a threchannel transceiver system is described for the transmission of biomedical signals with a maximum base band frequency of about 100Hz such as electrocardiograms (e.c.g.), electroencephalograms (e.e.g.), peripheral pulses (p.p.), and peripheral blood pressures (b.p.).