[SML] old TV trivia question

[Jerry Durand]

On the old TV series The Dick Van Dyke Show there's a large black
knob/disk on a wall plate next to the front door.  It's in most, but not
all episodes and the intro.

Any idea what that was?

-- 
Jerry Durand, Durand Interstellar, Inc.
www.DurandInterstellar.com
tel: +1 408 356-3886
@DurandInterstel

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