I still don’t recall an oscilloscope in William Hartnell’s Tardis and can’t find a photo that shows one. The original set only consisted of two walls. There was a TV screen set into the ‘computer wall’ generally used for showing what was going on outside of the Tardis, although I suppose it might have occasionally shown sine waves or Lissajous figures. This clip from the very first episode shows it was a very sparse set -Yes in some of the very first episodes of the original series, with the very old looking Doctor. The scope was sitting on a shelf, with a sine wave on the display.