The Handyprobe HP3 from TiePie Engineering, Sneek, The Netherlands, is a USB oscilloscope, spectrum analyzer, voltmeter, and data logger with a differential input capable of measuring voltages from 200 mV F.S. to 800 VDC (566 VAC). The device features 10-bit resolution, 100 Msps sampling rate, continuous streaming at 10 Msps, and a record length of 1 Msps. Amplitude accuracy is 0.3% F.S. The max. measuring time is limited by the available hard drive space. Applications include measuring mains power systems, switch-mode power supplies, power inverters, and serial communication buses such as CAN and Profibus. Included software turns the device into an oscilloscope, multimeter, spectrum analyzer, and transient recorder.