There is another version of the Arduino code that drives an OLED screen, although you still need a PC to kick the process off.

With his project, a 3-axis Open Source FFT Spectrum Analyzer he is not only entering the Hackaday Prize 2016 but also the highly contested field of acoustic defect recognition.

Read screenshot from HP8596E (or similar) spectrum analyzer via Arduino Uno R3 configured as parallel port (Centronics/IEEE1284) printer emulator, with Python program receiving, decoding and saving ...