bzzzt! wrong.

from Jargon File (4.4.4, 14 Aug 2003)
Bzzzt! Wrong.
 /bzt rong/, excl.

   [common; Usenet/Internet; punctuation varies] From a Robin Williams
   routine in the movie Dead Poets Society spoofing radio or TV quiz
   programs, such as Truth or Consequences, where an incorrect answer
   earns one a blast from the buzzer and condolences from the
   interlocutor. A way of expressing mock-rude disagreement, usually
   immediately following an included quote from another poster. The less
   abbreviated "*Bzzzzt*, wrong, but thank you for playing" is also
   common; capitalization and emphasis of the buzzer sound varies.
    

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