A storage device has a head that floats over a rotating storage medium. The retrieval unit retrieves a strong reflection object based on a signal strength which a frequency spectrum of a beat signal generated by mixing a transmission signal which is frequency-modulated and emitted and a reception signal which is formed in the transmission signal is reflected on a target indicates. A pick and place assembly retrieves electronic components, from a retrieved wafer assembly, and transports each retrieved electronic component to a shuttle assembly. A magnitude calculator receives the in-phase and quadrature digital values, and outputs a magnitude.