When this activity started, ATT long lines were running scared, because for the first time, outsiders can control their vast system. It was also possible to tie up lines between cities by stacking tandems back and forth between major cities. It was speculated that just a handful of hackers could do some serious damage to Ma Bell.

Other things like punching through busy signals was possible, for instance if someone's line is busy, an internal trunk code is used to "Tap into" that phone and hear conversations.

This infuriated the authorities, during a very paranoid time... Nixon was president, Hoover (of the FBI) was after dissidents and war protesters. Patty Hearst was kidnapped and eventually sided with the SLA.

Another strange quirk was General Telephone's Los Gatos system. It was possible to just pick up the phone, and slap the "hook switch" really fast, and presto, you're on an MF'able tandem. No 800 numbers to finger my hacking activities to the authorities.

Not even necessary to use 2600 Hz. Los Gatos was HACKER HEAVEN. Not only that, but when the called party hung up, it didn't time out. Polarity reversed when called party picked up the phone so had instant access to supervision as well.

Because of these amazing and damaging weaknesses discovered in their system, the authorities formed a secret grand jury to investigate the weaknesses in Ma Bell.

It is no doubt that Ma Bell's credibility was on the line, and that the authorities chastised Ma bell for their initial design.

It became customary for busted phone hackers doing jail time to educate other prisoners about these weaknesses, thus causing an even larger escalation in blue box usage as these people were released with this forbidden knowledge..