Looks like a neat little scope https://www.korg.co.uk/products/nts-2

4-channel oscilloscope

With dual stereo inputs, you can study up to four signals at once, comparing and overlapping them with ease. A variety of display modes let you see your data in colour. Its user interface is clear and quick, thanks to dedicated menu buttons and clickable encoder knob.

FFT/Spectrum analyser

NTS-2 comes with a dedicated FFT (Fast Fourier Transform) mode with a real-time spectrum analyser. These handy tools have always been out of reach for the synth musician - they either required expensive hardware or a computer nearby. Now you can carry them in your pocket!

Dual waveform generator

A flexible Wave Generator mode makes NTS-2 much more than an oscilloscope. It has two oscillators with dedicated outputs. Each oscillator can create a variety of waveforms – sine, square, triangle, sawtooth, pulse, and noise – whose shape and phase can be adjusted to suit many applications.

These sounds can be used in the audio range or as control voltage sources, and they can be set to cycle continuously or act as one-shot impulses; that means you can turn them into LFOs, envelopes, triggers, and control voltage generators, as well as sound sources. Attaching the NTS-2 to any patchable synthesizer instantly expands its power in useful ways, making it an analogue synth player’s dream tool.

Tuner

NTS-2 wouldn’t be complete without a precise and easy-to-use Tuner with multiple display modes!