... with variety of filtering methods: DFT, AC,EMG, Lowpass Filter, recorder Filter. Ensure the waveform clearly, accurately and nondeformed; LCD ... leads waveform, manu, heart rate, leads title, printing speed, filter etc; Single channel, 1+R(Rhythm)channel, 60 seconds ... 60 seconds compressible record need 10cm paper but for ordinal Single channel machine need 120cm paper.) to acquire long ECG signal ...