HeH......2600 became a magic number for it being the control tone used to "dump" one from a toll free number to the limbo of switching nexuxes Then by simulating an operator console you had the grandmaster key . The rest of the game was having a DTMF keyboard possessing the column 4 buttons ..... That and learning the codings which a little human engineering allowed one to use other skilled operators like a verbal man page for . An exercise in Google search seems akin to a flashback .... Statue of limitations is the only reason some of us don't belong to some big dude with the most ciggies . As for the contest in ancient tech- I may be a placeholder by there possibly being an asr-33 in the bowels of my storage barn unless it got thieved by former staff ! That asr had been used as a paper tape drive for a swtp 6800 my classmate inherited in 1982. IIRC the data was comma separated hard fielded ascii that would not be too hard to read today.