Captain Crunch whistle 2600 Hz

The famous Cap'n Crunch Whistle

Years ago, Cap'n Crunch cereal gave away a plastic whistle. Known as the Captain Crunch whistle, it makes a 2600 Hz sound. This proved to be the frequency used to sidestep the phone system's billing system back before digital phone switching (ESS) was implemented. People used Captain Crunch whistles to make free long distance phone calls.

John Draper, Joe Engressia, and Bill from New York were pioneering phone phreakers who used the Cap'n Crunch whistle. Mr. Draper later went on to construct blue boxes.

My introduction to such matters took a quantum leap forward when as a young, impressionable high schooler I read Secrets of the Little Blue Box by Ron Rosenbaum, Esquire Magazine (October 1971, unauthorized copy here) and the infamous June 1972 Ramparts magazine article on how to make a black box. (Can you say Radio Shack project?)

I have a Cap'n Crunch whistle. Or as the whistle itself says, a "Cap'n Crunch bo'sun whistle". Wanna hear how it sounds? No compare that to a pure 2600 Hz tone.

Big shoutout to Michael at Wall of Sound for jogging my memory, which inspired me to put this page together. Hats off to the producers of a show on phone freaking that stumbled across this page and borrowed by Cap'n Crunch whistle so Woz could blow it at the Tech Museum of Innovation in San Jose. The show has yet to air but I'm promised a credit.

Speaking of phones, here's an MP3 of the C tone used to break wiretaps as described by Matt Blaze.