The Safe and Sane Halloween - S4-E8
Revealing mistake: In this episode when the Gremlin, Goblin, Jack-o-Lantern, and Sam are peeking in through the back window, the gremlin turns to look at Sam when she is speaking and his ear passes through the area where there is supposed to be glass.
Answer: Telstar was an early communications satellite system. Darrin, in a particularly sexist manner reflective of this era, is saying that telling a secret to a woman means it is guaranteed to be "broadcasted" to multiple people.
raywest ★