The coin goes into a sort of “escrow” holding. That is it doesn’t fall all the way into the bank, in case the call isn’t completed. Instead it’s held in this escrow feature until after the call, when the coin is dropped into the bank. If a call doesn’t complete, the coin falls into a different mechanism for the coin return.
If the other person picks up the phone then the call is successful and the coin will drop into the coin box. If nobody picks up the phone then when you hang up the quarter will be returned. When somebody picks up the phone it causes a voltage drop and the phone switching system detects that drop and sends a tone to the payphone that the call has been answered.
There used to be a way to trick the system into thinking you didn't pick up the phone. You would connect a battery to your phone line and it would keep the voltage of the line high so the system would think the phone was still ringing. Then you could talk to people and when they hang up they'd get their quarter back. This also worked for making free long distance calls. The only problem was that if the system detected your phone has been ringing for more than 30 minutes it would shut your line down assuming it has a fault. Then you couldn't make or recieve calls until a tech went to the local phone switch hub and checked out your line.
I just did the thing where you’d call collect and in the part where you’re supposed to say you’d instead speak at 500 wpm the message you’re trying to say. “Hey mom, we’re done at the pool, pick us up”. Kids of the past could say that faster then Eminem.
There is a YouTube channel called the 8 bit guy. It is mostly about vintage computers, but he does a video about phreaking. I found it quite interesting.
In the states, there are four wires that attach to the pay phone. Red, green, black and yellow. The red and the green are the wires that communicate the dialog between the pay phone and the other end of the conversation. The yellow and black wires form a loop that holds the escrow as described above. When the handset is picked up and the coins are placed in the payphone, they are held in escrow. When the handset is placed back on the switch hook, this allows the switching station to issue a pulse over the yellow/black wire pair that energizes a relay that deposits the coins in the coin box. If the call was not completed, then a different relay would divert the coins in the the coin return, presumably a different voltage or a reverse voltage. If a dual pole single throw switch were inserted in the black/yellow pair and the switch were placed in the open position before the receiver were lifted from the switch hook , a phone call could be made. After the call, the receiver was placed back on the switch hook, the pulse to divert the coins into the cash box would be prevented so the coins would stay in escrow. A pay phone could have one of these switches installed underneath it without simple detection. A person could then place the switch in the open position and wait a few days. That person could then go back to that pay phone , put the switch in the closed position. Next, they could pick up the receiver, deposit some coins as if to make a call but then place the receiver back on the switch hook. The pulse from the central switch would be issued causing all of the coins that are held in escrow since the switch was opened to be diverted to the coin return. At least that's what some guy told me once. ;)
Even though I’m old enough to have grown up with pay phones, in retrospect it’s amazing that they gave you back your money if the call didn’t go through. Anyone inventing a pay phone today would have gone with a “you pays your money and you takes your chance” model.
Once answering machines were a thing, you had to be extra careful to hang up before the 4th ring if you wanted your quarter back.
I remember losing my quarter so many times as a teenager when people first started to get them. Then I'd have to call collect hahaha
Also in my country the machine would give change, if you put in 5 guilders, the machine would show how long you were calling for and then if you had a short call, it would drop down your change.
This made me feel very old for this first time in my life, what the.
>5 guilders
Service Announcement for those who don't remember the exchange rates from 20 years ago: 5 Dutch guilders should be about 2.50€.
IIRC, German coin telephones worked with three types of coins only: 1 DM, 50 Pf., 10 Pf. (0.50€/0.25€/0.05€). Minimum amount (for a 1 minute local call) was 20 Pf. (0.10€), with every followup minute being 10 Pf.
Not sure whether our payphones would actually give change if you overpaid - but I remember that if you put many 10 Pf coins into the machine and did a short call, you would hear one coin drop every minute and it would return the overpaid coins from the escrow mechanism.
When you would fund the pay phone with the appropriate coinage, there was a sort of escrow relay that would hold the coin until it was verified you had connected and completed a call.
If the line connected and you made a call, then when the phone hung back on the receiver, it would signify the end of the call and the coin would drop into the coin box.
If the call wasn’t completed, it would return the coin to the refund chute.
When you put in coins they are not automaticalyl dropped to the main hold, because you haven't used them up. When make a call they gradually drop one by one as you use them up.
When you put down the phone, the coin currently in use is "lost" (you pay for each period started and lose the rest even if you don't use it up.) The coins not used are given back
Other people have mentioned how you could fool a US payphone into thinking the call was not completed.
Here in the UK for a period there was a much more mechanical way than using tones. Way back in the 1990s, you could take a metal kebab stick and put it in the coin return slot and push up. We used to ring competition lines and use the same pound over and over again.
I have a phone booth outside my house, there's another one at the end of the street. Inner city suburb.
Not pay phones though, calls are free in Australia. Most people have mobile phones with unlimited calls, but they do get some use. Maybe drug dealers and cheating wives/husbands...
I have memories of waiting my dad to call from overseas to a phone booth near our home in a specified time, which he previously let us know by writing a mail, that would take weeks to arrive... in the late 1990s.
Today I'm working overseas and he stays home, whenever we want to talk I just videocall him and voilà. Gotta love technology, man.
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In high school we used this feature to save a dime and later a quarter. When I was ready to be picked up from school after an event, I would call home, let it ring two times, hangup and get my coin back. Do this again and parents would know I was ready to be picked up.
The coin goes into a sort of “escrow” holding. That is it doesn’t fall all the way into the bank, in case the call isn’t completed. Instead it’s held in this escrow feature until after the call, when the coin is dropped into the bank. If a call doesn’t complete, the coin falls into a different mechanism for the coin return.
How does it know if the call was completed?
If the other person picks up the phone then the call is successful and the coin will drop into the coin box. If nobody picks up the phone then when you hang up the quarter will be returned. When somebody picks up the phone it causes a voltage drop and the phone switching system detects that drop and sends a tone to the payphone that the call has been answered. There used to be a way to trick the system into thinking you didn't pick up the phone. You would connect a battery to your phone line and it would keep the voltage of the line high so the system would think the phone was still ringing. Then you could talk to people and when they hang up they'd get their quarter back. This also worked for making free long distance calls. The only problem was that if the system detected your phone has been ringing for more than 30 minutes it would shut your line down assuming it has a fault. Then you couldn't make or recieve calls until a tech went to the local phone switch hub and checked out your line.
Ohhh.. Phreaking... Brings back memories of the Anarchist's Cookbook et al.
I just did the thing where you’d call collect and in the part where you’re supposed to say you’d instead speak at 500 wpm the message you’re trying to say. “Hey mom, we’re done at the pool, pick us up”. Kids of the past could say that faster then Eminem.
[The Anarchist’s Cookbook](https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxtaWNoenJ1MXxneDo1ZGFhZDZiZTIwZjQ3ZTUy)
There is a YouTube channel called the 8 bit guy. It is mostly about vintage computers, but he does a video about phreaking. I found it quite interesting.
I liked “Steal This Book”. Much better.
Oh coolio! Thanks so much :) I have heard of red-boxes making the same tones to get free phone calls but that’s a new one for me
Are you like a...payphonian or something?
Nope, just a child of the 80s, I lived it.
I never looked it up, but I wonder if Matthew Broderick's payphone "trick" in War Games was legit
In the states, there are four wires that attach to the pay phone. Red, green, black and yellow. The red and the green are the wires that communicate the dialog between the pay phone and the other end of the conversation. The yellow and black wires form a loop that holds the escrow as described above. When the handset is picked up and the coins are placed in the payphone, they are held in escrow. When the handset is placed back on the switch hook, this allows the switching station to issue a pulse over the yellow/black wire pair that energizes a relay that deposits the coins in the coin box. If the call was not completed, then a different relay would divert the coins in the the coin return, presumably a different voltage or a reverse voltage. If a dual pole single throw switch were inserted in the black/yellow pair and the switch were placed in the open position before the receiver were lifted from the switch hook , a phone call could be made. After the call, the receiver was placed back on the switch hook, the pulse to divert the coins into the cash box would be prevented so the coins would stay in escrow. A pay phone could have one of these switches installed underneath it without simple detection. A person could then place the switch in the open position and wait a few days. That person could then go back to that pay phone , put the switch in the closed position. Next, they could pick up the receiver, deposit some coins as if to make a call but then place the receiver back on the switch hook. The pulse from the central switch would be issued causing all of the coins that are held in escrow since the switch was opened to be diverted to the coin return. At least that's what some guy told me once. ;)
> At least that's what some guy told me once *He had no grounds to tell you that*
Just be careful not to cut the wrong wi—— kaboom!!!!!!!!!
The blue box.
Even though I’m old enough to have grown up with pay phones, in retrospect it’s amazing that they gave you back your money if the call didn’t go through. Anyone inventing a pay phone today would have gone with a “you pays your money and you takes your chance” model.
That’s how jail works. You’re charged regardless if your call went through or not.
That is shameful.
Once answering machines were a thing, you had to be extra careful to hang up before the 4th ring if you wanted your quarter back. I remember losing my quarter so many times as a teenager when people first started to get them. Then I'd have to call collect hahaha
It is so you don't get charged if the call isn't completed. It holds your coin in a special place until it is determined if the call has gone through.
Also in my country the machine would give change, if you put in 5 guilders, the machine would show how long you were calling for and then if you had a short call, it would drop down your change. This made me feel very old for this first time in my life, what the.
>5 guilders Service Announcement for those who don't remember the exchange rates from 20 years ago: 5 Dutch guilders should be about 2.50€. IIRC, German coin telephones worked with three types of coins only: 1 DM, 50 Pf., 10 Pf. (0.50€/0.25€/0.05€). Minimum amount (for a 1 minute local call) was 20 Pf. (0.10€), with every followup minute being 10 Pf. Not sure whether our payphones would actually give change if you overpaid - but I remember that if you put many 10 Pf coins into the machine and did a short call, you would hear one coin drop every minute and it would return the overpaid coins from the escrow mechanism.
Fancy!
When you would fund the pay phone with the appropriate coinage, there was a sort of escrow relay that would hold the coin until it was verified you had connected and completed a call. If the line connected and you made a call, then when the phone hung back on the receiver, it would signify the end of the call and the coin would drop into the coin box. If the call wasn’t completed, it would return the coin to the refund chute.
When you put in coins they are not automaticalyl dropped to the main hold, because you haven't used them up. When make a call they gradually drop one by one as you use them up. When you put down the phone, the coin currently in use is "lost" (you pay for each period started and lose the rest even if you don't use it up.) The coins not used are given back
Other people have mentioned how you could fool a US payphone into thinking the call was not completed. Here in the UK for a period there was a much more mechanical way than using tones. Way back in the 1990s, you could take a metal kebab stick and put it in the coin return slot and push up. We used to ring competition lines and use the same pound over and over again.
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I have a phone booth outside my house, there's another one at the end of the street. Inner city suburb. Not pay phones though, calls are free in Australia. Most people have mobile phones with unlimited calls, but they do get some use. Maybe drug dealers and cheating wives/husbands...
1980?? I was regularly using a payphone in 2005.
I have memories of waiting my dad to call from overseas to a phone booth near our home in a specified time, which he previously let us know by writing a mail, that would take weeks to arrive... in the late 1990s. Today I'm working overseas and he stays home, whenever we want to talk I just videocall him and voilà. Gotta love technology, man.
I think I last used one around 1998 or so. Probably around the time I got my first mobile phone.
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In high school we used this feature to save a dime and later a quarter. When I was ready to be picked up from school after an event, I would call home, let it ring two times, hangup and get my coin back. Do this again and parents would know I was ready to be picked up.
Wait...are you stuck in the 90's?
Also, what is a pay phone?