I don't have any training but am doing some hobby electronics. I would like to record a change in voltage over time, sampled at around 100+ kHz. Ideally, I'd like to record around 20-30 min of two different channels, so I guess that works out to be at least 240 million samples. I'd like to view this recording on my Windows computer similar to a stereo .wav PCM waveform. (In fact, if I could save it as a .wav file, that'd be ideal.)
I considered simply using a sound card to make this recording, but this seems to not be possible with a DC signal.
Is this something that a digital oscilloscope can do? Or is there a tool designed for this specific task of recording to a file, similar to the line-in on a sound card? Converting to digital and streaming over USB to record on a PC seems to be what I'm ideally looking to do.
Edit: Giving some context as requested... This is for a latency test. I am wanting to record a variable latency of a video game system plus an HDMI adapter. Using a photodiode I can create a voltage stream that will show when the result appears on screen and compare it to when a button was pressed. (Hence why two channels are needed.)