I know Green Acres borrowed several characters from Petticoat Junction but it wasn't until a few years ago I learned Arnold's debut was on Petticoat Junction. As far as I can tell, the episode "A Matter of Communication" was the first episode with Arnold. As of right now it's available on Youtube. There's a brief scene with Mr. Ziffel and Arnold and they interact much the same way they would on GA.
This was season 2 of PJ, the year before GA went on the air. Of course it was written by Jay Sommers (and even directed by Richard L. Bare) but I thought it was interesting that one of the most iconic characters of GA didn't even debut on that show.
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the Clampetts are in a fancy Beverly Hills jewelry store. Granny points to a tray of rubies.
Granny: "How much fer one o' them red diamonds?"
clerk: "Madam, those are rubies."
Granny: "OK ask her kin we buy one offa her."
clerk: " The ruby I am talking about is not a lady."
Granny: "Lissen, how she got them diamonds is her business. I'm just sayin' ask her kin we buy one from her."
Arnold's first appearance
