Keritech VS-1 Vectorscope overview and upgrade

One of my projects - the VS-1 vectorscope, in other words, an X-Y only oscilloscope, no timebase. I built it on a stripped chassis of a Radiotechnika ST-310A single channel scope that didn't work. The device has several functions: 1. audio 2. X-Y scope, BNC inputs 3. curve tracer 4. scope clock (for the future) 5. calibration mode The vectorscope's 1kHz sine wave oscillator and curve tracer were made based on @MrCarlsonsLab patron-only curve tracer project. All else was designed and redesigned from the grounds up by yours truly. In this video I do a vectorscope modification to make it work with all audio sources, regardless of the signal's phase or the vertical/horizontal assignment to L and R channels. Of course, some of you might mention that channels could be easily swapped if I used RCA plugs or tip-sleeve phonejacks... I used a TRS jack for its simplicity and reliability, and the ability to use a 3.5mm or 6.3mm to 6.3mm jack cable for connecting the scope to any device with a he