candlestick
phones wind-up
phones public phones
1920s-1930s manual
telephone
exchanges area codes
and
direct dialling using a
dial phone
1940s-1950s public phones
1940s-1950s costs of calls
1940s-1950s illegal
free calls
1940s-1950s house
phones
1940s-1960s telegrams
importance
in the past telegrams
from sending
to delivery

Illegal free calls from old public phones

How the public could make free, illegal phone calls from phone boxes in the early years of telecommunications. Childhood recollections of the webmaster with original contributions from others with their firsthand experiences, edited together by the webmaster.

Today free calls to anywhere in the world are readily available with the likes of apps Skype, WhatsApp and Messenger. It was not always so. In the early days of telecommunications, phone calls were expensive in real terms. So free calls were appealing. There was also the feeling, particularly among teenagers that it wasn't really stealing from somwhere as huge as the General Post Office (GPO). It was also fairly safe to do it from a phone box, because it was impersonal, in that you could run away afterwards - and it was easy. Read on:

The principle behind making free illegal calls

The procedure behind making a free call on a dial phone was to mimic the clicks that came from dialling to the number that one wanted, i.e. one click for one, two clicks to two etc. There were several ways to do this as described below.

The procedure worked for all dial phones, both public phones and housephones, but I only knew it done from public phones. Free calls were illegal and a clear get-away route was essential to prevent being caught. Normally only older children and teenagers took the risks.

Simple free calls: tapping the cradle

Clicks to mimic dialling clicks could be made fairly easily by jogging the cradle up and down fairly rapidly at the same rate as dialling. This was easier said than done, but it was possible to become quite proficient at it.

Example from the 1950s

In the 1950s when I was a teenager - and possibly as early as the 1930s and 1940s, I knew fellow-teenagers who did it, and I knew how to do it, although I never dared to do it myself . I thought that if I did, a police car would come roaring round the corner, sirens screaming, and cart me off to a police station. As far as I know, though, on-one was ever caught.

Example from the 1960s

contributed by James Chalmers

When I was a student in the 1960s in Brighton I was with a guy in a phone box when he called every cinema in town (probably about six) to ask what film was on and what time the shows started. All the calls were free. He achieved this by successfully tapping the numbers out on the receiver rest (cradle). He only made one mistake and got the wrong number, but he managed to get the right number on his second attempt.

Example from the 1980s

contributed by Kevin McGuire

I know for a fact that tapping the cradle to make free calls in phone boxes was still possible as late as the early 1980s in Scotland, but I can't speak for elsewhere.

contributed by Kevin McGuire

My friend's parents put a lock on their housephone which stopped the dial from turning. They didn't know that we could still make calls by tapping out the number. This was long before the days of itemised billing, of course.

The worst offenders

contributed by James Chalmers

When I worked for the Plessey company in Liverpool which made telephone exchanges, those in the know told me that the worst offenders for making free calls were the policemen on the beat. They were given an allowance of 2 pennies (tuppence) to make check in calls to the station, but they kept the money and tapped out the number on the cradle. They were experts at it.

I understand that the police could use the phones in police boxes free, but there were fewer of them around, and probably only went through to the police station and emergency services.

Back dialling

contributed by James Chalmers

This guy showed me another way to make free calls, by what was called back dialling: Turning the dial all the way round and allowing it to run back to what I think was nine minus the number - or it could have been ten.

More methods for making illegal free or cheap calls

contributed by Mervyn Webb, 57 years' service in telecommunications, starting when it was still the GPO (General Post Office)

There were other methods to make illegal free or cheap calls from button A and B boxes.

1. This method relied on the fact that dialling O for the operator. So if you were making a call to your local exchange say to subscriber 201 - all small exchanges (of UAX type) were only 3 digits - all you had to do was pick up the phone, tap the phone rest twice for the 2, dial the O on the dial, and then tap once for the 1.

The exchange knew what was happening as the dial pulses would be at the wrong speed but there was nothing to stop it happening.

2. You could also make long distance calls for the price of a local call by going to a phone linked to an exchange area furthest away from you. There was a suitable list in phone boxes, listed in the general direction of the distant exchange you wanted to call. Go to a phone box in that area and write down the local code to the next furthest exchange and so on until you reached the exchange you wanted. You then had to dial a long string of digits and you could get through to the distant end. It did work, but may not have been worth the trouble.

The trick came to an end with 'route restriction' equipment.

Reverse charges

contributed by James Chalmers

Another trick for free calls which did take a bit of setting up was to make a reverse charge call from one phone box to the other via the operator - all done with false names of course. At that time the operators couldn't tell if they were calling a phone box or a private number.

Cheap calls exploiting the person-to-person facility

contributed by James Chalmers

At one of the places I lived as a student, the landlord had installed a coin box phone in the hall for the students to use. He worked for the post office so there was never any question of our trying to get free calls with him prowling around. On one occasion, though, we did get exceptional value for our money, albeit with a waste of our time: We made a person to person call from this phone to a student friend in a London Hall of Residence. They took over an hour to find him and bring him to the phone, but in the end the call cost just a few pence because it was only charged from when he came to the phone and confirmed his name.

Free calls with specialist equipment

All the methods for the illegal free calls described above were available to ordinary people. There were, though, other methods for those who knew a special code or trick to bypass the exchange, or had access to a device that could generate the sounds that mimicked the dialing clicks or had access to specialist equipment. The methods were illegal and risky, as they could be detected by the telephone company or law enforcement.

Specialist equipment to enable free calls

from ChatGPT

• Blue boxes: These were electronic devices that could produce the tones used by telephone companies to control long-distance calls. By using a blue box, one could dial an operator, play a certain tone to seize the trunk line, and then dial the desired number for free. Blue boxes were popular among hackers and phreakers (phone hackers) in the 1960s and 1970s, and some famous users included Steve Jobs and Steve Wozniak, the founders of Apple.

• Black boxes: These were devices that could trick the telephone exchange into thinking that a call was not answered, and thus not charge for it. A black box would answer an incoming call, but keep the line open without sending a signal to the exchange. The caller and the receiver could then talk for free until one of them hung up.

• Red boxes: These were devices that could simulate the sounds of coins being deposited into payphones. By using a red box, one could make free calls from payphones by playing the appropriate tones for each coin.

• Loop lines: These were pairs of phone numbers that were connected internally by the telephone company for testing purposes. By dialling one number and then quickly dialling another, one could create a loop that allowed two parties to talk for free. Loop lines were often discovered by phone freaks who scanned the phone network for them.

The end of risky illegal free phone calls

All the above methods became obsolete as technology advanced and telephone systems switched from analogue to digital. Today completely free calls are readily available thanks to apps like Skype, WhatsApp and Messenger. What's more, they are video so that people can see one another as they talk. We could never have imagined it back in the day.

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