I, Darrin, Take This Witch, Samantha - S1-E1
Audio problem: When Samantha and Darrin are at his ex-girlfriend's house for dinner, Samantha is doing all kinds of things to sabotage the dinner, even making a gust of wind come through the front door thus blowing the ex's wig off. The ex girlfriend is screaming but the screams don't match up to what her mouth is doing.
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 ★