Imagine making a toy that can accidentally cost a company millions of dollars. That’s exactly what happened to AT&T because of the Ohio-based General Mills cereal company, with a toy that was released in the 1960s in a box of Cap’n Crunch.

It was in a specific box that they had put a children’s toy whistle, which apparently could produce a perfect 2600 Hz tone. Now, why would this be of any significance? Well, because a man named Sid Bernay, who was said to have perfect pitch, was also a phone phreak, helped exploit this.

Phreaking refers to people who study and experiment with telecommunication systems, which is something a man named John Draper knew very well about, as he was friends with Bernay.

As The History Archives described on their Facebook post, they describe the illegal actions that cost AT&T millions of dollars and exposed some serious flaws in their security:

This specific tone was a security key for the AT&T phone network. When played into a phone receiver, it tricked the system into thinking a long-distance call had ended, opening up the line for new routing commands. This allowed a user with the right knowledge to make free calls anywhere in the world, essentially seizing control of the trunk lines that connected cities and countries.

Because these guys studied telecommunications devices, they were able to manipulate them even further, as they continue:

Draper took the concept further. He created a device known as a “blue box,” an electronic gadget that could generate a wide range of tones to manipulate the phone network in even more complex ways.

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Gallery Credit: John Robinson