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Comment by ben509 | Hacker News Reader

You could, in fact, dial them one-handed. A rotary phone uses pulse dialing; as the rotor turns it opens the circuit briefly, if you dial 5 it sends 5 pulses. So you can do the same by pushing the switch repeatedly and pausing in between each number as though the rotor was spinning back.

Same trick works on touch tone phones since the networks still support pulse dialing.

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Once as a kid I managed to misdial the emergency number (112) by just randomly pressing the switch, unaware of the trick and with no intention of calling anywhere.

I wonder if the emergency worker believed me when I apologized for accidentally calling him.

I had a similar experience doing some wiring on the phone jack and probably shorted the wires just the right number of times. At some point I heard a voice telling me I'd dialed the wrong emergency number (999 or 000 or something) and to hang up and dial the correct one (111 in my country). Lucky it was wrong because if I hadn't been able to receive their call back since I was working on the wiring, a cop would probably have turned up.

It sounds like you were in a country where the number 112 was just 4 pulses in total, which is easy to accidentally dial. Some other countries require 3 sequences of 9 or 10 pulses (000, 111, or 999). 111 in New Zealand where the digit to pulse count mapping is reversed.

Wind blowing on overhead telephone wires could cause this with is why 999 and 911 where used for Police in The UK and US

I recall a friend of mine (when we were teenagers in the 80s) whose parents had a physical lock on their phone to prevent the dial turning (to prevent their kids running up phone bills I assume). Unlike his parents, my friend was aware of the "trick" you describe.

There was an information kiosk phone in the student union of my alma mater that could make long distance calls with pulse dialing using a button on the handset. It was well used.

This was something that worked on pay phones (in the UK at least) to get free calls. I think it was around the 70s/80s? I can't remember the exact mechanism, but something like the coin unlocked the dial, so if you didn't need the dial you could make the call without a coin.

The good ol days of inband signaling / payment schemes ;)

Some of the networks don't support pulse dialing anymore. Many of the Analog Telephone Adapters people use to access voip accounts don't either.

They make adapters to allow rotary on such systems:

https://www.dialgizmo.com/

You needed really fast fingers for this. The minimum is about 8 Hz. I could do it as a teenager, but I don’t think 70yo senators are going to like it.

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