| 摘要 |
PURPOSE:To prevent a recording error caused by a variation of a characteristic of an insulating amplifier, by providing a calibrating signal generating part on each channel and correcting a recording signal, in a multi-pen recorder using the insulating amplifier. CONSTITUTION:A changeover signal CH is applied to a photocoupler 16 of each insulation amplification system 2A-2N through an output port 10 from a microcomputer 6, and each switching circuit 12 is changed over so as to receive each input signal. As a result, an input signal is A/D-converted 5 through an insulating amplifier 13 and a multiplexer 4, and is inputted to the microcomputer 6. Subsequently, a changeover signal CH is outputted through the output port 10 from the microcomputer 6, calibrating signals r1-rm are outputted in order from a multiplexer 14, are inputted to the insulating amplifier 13 through the changeover circuit 12, and are stored in the microcomputer 6 in the same way as the recording signal. In this way, in accordance with this stored calibrating signal, the recording signal stored previously is calibrated, is D/A-converted, and is held 8A-8N. |
