With so many building blocks available; what would take to display two probes in X-Y mode on a LCD television ? No preference if from composite, component, USB, HDMI...
Just few MHz bandwidth...

??? ----> https://www.newegg.com/p/231-0099-0..._re=usb_audio card-_-231-0099-00002-_-Product

 

A RPi with analog input stages on the SPI would work using the HDMI port for the display driver.
https://blog.adafruit.com/2016/04/2...exy-plotter-piday-raspberrypi-raspberry_pi-2/

https://forum.allaboutcircuits.com/threads/raspberry-pi-daq-system.75543/post-865187
It would be pretty easy to just have a X/Y opengl program display the analog signals.

 

There are plenty of options for interface boxes that turn your Laptop into a Storage-Scope.

Virtually any Laptop can drive a TV through an HDMI Cable.
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