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by slyall 1477 days ago
A friend of mine had a system for getting free calls from New Zealand payphones.

He installed a small switch between the payphone and the line before it went into the ground. He then exploited the lack of coordination between the phone and the exchange.

* First he would pick up the phone and start dialing 0800 (equivalent of 1-800), the phone would see this was a free number and ignore what was being entered next.

* Then he would briefly interrupt the line. The phone wouldn't notice but the exchange would think the call had ended.

* Then he would dial a new number. The exchange would think the payphone was making sure he paid, while the payphone would think he was still dialing a free number.

So to call 0900 123 456 for free he would dial 0800-click-0900123456

Obviously the phone company audits quickly turned up a problem but he got away with it for a little while.

1 comments

Glad to know I wasn’t the only kid trying, by hook or crook, to figure out what was on the other end of those 900 numbers. :D