Blue box
A Blue Box is an electronic circuit with a 2600 Hz tone can be produced. This tone was (eg in the United States, Japan and France) used by CCITT v5 -compatible exchanges in order to display each other conversation redirects. When phreaking so were surreptitiously free phone calls. More modern switching technology no longer allows for the Blue Boxing.
Was discovered in the Blue Boxing by Joe Engressia. Engressia discovered by chance that he could make free phone calls by whistling a four-line e. This clay was used by the former telephone company in the 1960s AT & T to regulate the line seizure. The hobbyist John T. Draper extended the method with their own knowledge greatly, and made it unconsciously a subculture of hacking. John T. Draper later called himself "Captain Crunch " because of the 2600 Hz tone could also be produced with a plastic pipe made from a bag of Cap'n Crunch breakfast cereal. He was shortly afterwards arrested by the FBI and subsequently sentenced to five years' probation.
If one chooses a phone number in the same central office ( local exchange ) is connected as your own phone, the connection is made directly ( " local call "). When dialing a phone number that is outside of their own switching range (for which the code is needed ), the mediation of own foreign exchange needs to indicate that a connection request is present ( " long distance "). This was done in ancient times, first with the help of 2600 Hz pulses later with multi-frequency tones ( DTMF tones similar to a key telephone), which were transferred via a pipeline to the remote exchange.
The Bluebox took advantage that the control signals were transmitted on the voice channel, were so audible. Thus, it was also possible to send the tones from an ordinary telephone to control a connection between the two switches.
Had the party hangs up (and thus stopped the charge meter 's own exchange), one generated with the Bluebox first a 2600 Hz tone to get a free transmission. Then you chose 2600 Hz pulses, the phone number (the principle was similar to the pulse dialing, only with tones ). The obvious advantage was, of course, that this charge meters of its own switch was bypassed because the foreign mediation assumed that this was active. Later built John T. Draper so-called multi-frequency devices with which he was able to generate more sounds. They were initially called MF boxes. As Draper gave one of the first MF boxes to the blind boy Joe, wanted to know the color. Because John T. Draper had incorporated the frequency generator in an old blue box, Joe insisted to call the device Blue Box. Later the term Blue Box prevailed as a term for the method itself and the world as Blue Boxing was known.
In addition to the blue box there was later a number of other so-called Color Boxes. So there was the Red Box, with which you could make free calls from payphones, by imitating the sounds that follow the coin. Other devices were the Aqua Box, phone tracebacks disturbed, and the Rock Box, which was used to transfer music through the telephone network.