A simple non expensive device for biosignal acquisition is presented. It mainly meets the requirements for didactic purposes specific in medical informatics laboratory classes. The system has two main types of devices: ‘student unit’- the simplest one, used during lessons on real signals and ‘demo unit’ which can be also used in medical practice or for collecting biological signals. It is able to record: optical pulse, sphygmogram, ECG (1-4 leads) EEG or EMG (1-4 channels). For didactical purposes it has a large scale of recording options: variable sampling rate, gain and filtering. It can also be used in tele-acquisition via Internet.