On Facebook, Bobby Ellerbee writes:

In Case You Missed This…’Sanford And Son’, NBC Burbank
In yesterday’s posts on NBC Burbank, Mike Newell reminded us of this “show within a show” episode of ‘Sanford And Son’ shot in Studio 4. It’s cued up to the start of the studio sequence. Enjoy and share!

http://youtu.be/K_uiD6OtYRs?t=5m4s