cheese box

The device could originally be fitted into a wooden box intended for cheese. Compare blue box.

cheese box (plural cheese boxes)

1. A device formerly used by phreakers to convert a home telephone line into a payphone.
   • 1967, William Surface, Inside Internal Revenue

     Then the bookie leaves the site of the phone and stations himself blocks away in another room with a phone attached to a similar cheese box.

   • 1978, Bell telephone magazine (volumes 57-58)

     The cheese box bridges two separate telephone lines. It is often used by bookmakers and bettors to place free calls for accepting or placing bets.

   • 2009, Emmanuel Goldstein, The Best of 2600, Collector's Edition: A Hacker Odyssey, page 40:

     There are files circulating about the modem/phreak world regarding a device known as a cheese box.