Omega RD3057 is a high-quality portable recorder offering a wide range of features for accurate and reliable measurements. It has a DC-servo pen drive and is available in 1- or 2-channel versions. The effective recording span is 150mm, and there are 12 measuring ranges from 10mV to 50V full scale. The recorder can be used in vertical or horizontal operating positions. It uses a contactless ultrasonic pen position transducer for reliability and long life. Both Z-fold or roll charts can be used.