5m recording by G5UM

Many years ago Jack Hum G5UM gave a talk to the Cambridge radio club (CDARC). In the talk he mentioned he had made a recording in the late 1940s of the last hours on 5m in the UK. I am not sure if this was a disk, wire recorder or tape, probably a disk.

I am wondering if copies of this historic recording still exist? At the time I think G5UM lived in London.

Many will remember Jack as the columnist of the "Four Metres and Down" column in RadCom.