"David Brinkley early TV news goof-up" joke

Early TV news (late 1940's - early 1950's) was highly experimental, broadcast "live," and plagued with unforeseen on-the-air foul-ups.
David Brinkley writes in his new autobiography, "David Brinkley - A Memoir," of a particular incident he endured in the pre-Huntley days - one of those things you can laugh at later, but seems like a nightmare when it's happening. (Printed without permission:)
"One of Brinkley's first regularly-scheduled NBC TV news reports was five minutes of air time at 6:00 p.m. filled with scraps of film gathered during the day by a single cameraman, George Johnson, a nice young man totally inexperienced and untrained in journalism, working with a handheld, spring-wound silent-film camera, a Bell and Howell Filmo, wandering alone around Washington during the day looking for something, anything, to put on the air that night.
Whatever he brought in was broadcast while I sat in a tiny studio out of sight of the audience looking at a television screen and narrating film I had never seen before.
Rehearsals? There were't any.
While the film ran, I talked behind it, an engineer somewhere else in the building played background music from a phonograph record.
Background music? Yes, we still thought we were doing newsreels and they always had music, didn't they? Yes, of course. Predictably, this messy procedure brought to the screen some perfectly terrible programs.
This was the worst: One day, George Johnson brought in four small film stories. When they were spliced together, the first in line was a funeral of a departed dignitary in Arlington cemetery.
The second and third stories I have forgotten. The fourth was about some kind of experiment with sheep at an Agriculture Department station in nearby Maryland. The film was delivered to the control room to be threaded into the projector. It was threaded in, but backward.
Nobody noticed. At 6:00 p.m., the projector started, and somewhere down the hall an engineer started the music. What went out on the air was sonorous, funereal music suitable for a burial in Arlington while on the screen was a picture of a sheep upside down.
I sat, stunned and confused, in the little studio looking at and listening to this mess and wondering what in God's name I could do or say.
Nothing, as it turned out. Looking at an upside-down sheep I could do or say nothing but keep quiet and let it run out to the finish. But others said it for me. For years after, people on the streets and in elevators asked me, 'You ever get that sheep back on its feet?'"