Hacker News Reader

Comment by marzetti | Hacker News Reader

Thanks for this article and the comments. Reminds me of a trick we kids did in the early 60s (yeah, sorry) with the British 'phone box' pay phones. We called it 'tapping the phone', but it wasn't spy style listening. Passed from kid to kid the amazing trick was you could dial the number by tapping the handset (10 taps for zero, 9 taps for 9, ..) and the phone would ring the number but you didn't then have to 'press button A' to speak.. you simply made the call, spoke normally, hung up, and pressed button B to get your money back! Sadly, I never tried international calls... When we moved to New Zealand around '63-4, I discovered the phone dial was reversed, in the UK it was 1-9,0, in NZ it was 9-1,0. (So emergency calls were 111 not 999 as in the UK.) The trick still worked but, except for 0, you had to '10s complement' the taps. Maybe because of that none of the kids I knew at the time in NZ appeared to know the trick...

View on HN

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.

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

When I was a kid, we had a trick here in Spain to make free calls in public pay phones. When the other person answered, you had to hang up, wait about half a second and then pick up the phone. The head piece was in a lever, so you had to manipulate that lever. The further the call recipient, the longer you had to wait to pick up. For a person 50 kms away you had to wait a bit over a second, if I recall correctly.

We used to get the money back with a pretty reliable mechanical method, stuffing a flattened MacDonald's straw into the machine above the spare change slot and jiggling in and out. You needed a coin for the call but could return and re use it each time or even for the same call.

In Sweden, at the high school I went to, we had pay phones which would behave as if you had inserted a coin if you zapped it with static electricity. We used this for a while to make prank calls to other countries. Typically to random numbers we just tried, sometimes in the middle of the night in the other country.

This is because the NZ answer was to use a regular land line, and dial extra numbers on the end, the exchange would work, but their billing system would throw out the call, giving it to you for free.

Reply on news.ycombinator.com