Spiro (device)
From Wikipedia, the free encyclopedia
Spiro was the name given to the blue box, a piece of telephone hacking equipment used in the 1970s to make long distance telephone calls without being billed. In a sarcastic reference, it was named after Spiro Agnew, the vice-president of the United States at the time, who was greatly unpopular with the youth and counterculture who largely made up the telephone hacking community. Other pieces of hacking equipment were named the Agnew, and even the T, Agnew's middle initial.
The Spiro consisted of a set of audio oscillators, a telephone keypad, an audio amplifier and speaker. Its use relied, like much of the telephone hacking methodology of the time, on the use of a constant tone of 2600 Hz to indicate an unused telephone line. A free long distance telephone call (such as the information operator from another area code) was made using a regular telephone, and when the line was connected, a 2600 Hz tone from the Spiro was fed into the mouthpiece of the telephone, causing the operator to be disconnected and a free long distance line to be available to the Spiro user. The keyboard was then used to place the desired call, using touch tone frequencies specific for telephone operators. These frequencies are different from the normal touch tone frequencies used by telephone subscribers, which is why the telephone keypad could not be used and the Spiro was necessary.
Development and use of the Spiro was largely enabled by Bell Telephone's policy of publishing all technical documentation regarding its equipment. In response to the development of this and other means of telephone hacking, the company began to develop other means of securing its system, without publicly disclosing the details. This, plus the investigation and prosecution of several hackers by the FBI, finally made the Spiro and other hacking equipment obsolete. The hacking community evolved into other endeavors, however, and there currently exists a commercially published hacking magazine, titled 2600, a reference to the 2600 Hz tone that was central to so much of telephone hacking.