How did actually the prepay telephone work (A foreigner needs explanation?)

[dsk]

It is obviously some differences in the way to handle it.  I guess in the earliest day a local call was 1 of unlimited time in USA and Norway.

In the 70ies we still had dump payphones, but had to add more money every 3 minutes. (more often at automatic long distance) and it was no operator involved.

How did you do this, was it any time limit? Did the exchange automatically demand fore more money? Did it receive automatically information of inserted coins (number, value)

In the 70'ies we started using 16kHz signalling. 1 beep collecting one coin, and the paystation kept the order of whats the remaining credit. When no more credit, the phone itselves hung up.

I have observed my 120B payphone has a printed circuit with several options, minimum amount several ways of working etc, but I do not really understand what the options do.

I guess theaching me this will be like teaching a 10 year old boy how it worked in the 1980'ies.  (="really old days)   

In advance
Thank you for all help.

dsk

[mentalstampede]

In my hometown in GTE territory local calls were unlimited on time.  When I was growing up in the 1980s, the phones were all AE120 types. They gave you dial tone when you lifted the handset, you would deposit the base rate, dial your call, and talk as long as you wanted.  I don't recall ever making an operator assisted or long distance call on one, so I can't help you with that.

[dsk]

Thank you, about whats common in Norway up to they started with the 16kHz.

dsk

[mentalstampede]

There are still a very small number of AE120s in service in my hometown that are not COCOTs.  Four of them to be exact.

I'll have to stop by one and play with it sometime soon.

[dsk]

What else can I say?
Thank you! 

dsk

[poplar1]

Western Electric multi-slot prepay phones---for most of their existence anyway--were Coin First (CF). They did not have dial tone when you first went off-hook. The special coin lines were ground start; in order to draw dial tone, they required a path to ground through the coin relay assembly that occured once the coin(s) entered the hopper.

Most of them were untimed on local calls. Some places, such as New York City, did have timed calls with overtime charges. The operator would come on the line to tell you to deposit another 5c for x additional minutes. Later that process was automated.

Later on, many WE prepay were converted to Dial Tone First. This meant disconnecting the dial shorting contacts on the coin relay, among other changes. Additional central office equipment was required to allow free calls to "0" (operator), 411 (directory assistance), and 911 (where available, for emergencies).  7-digit calls that were attempted without depositing 10 cents were diverted to an automated announcement telling caller to hang up, deposit 10c, then dial again.

Ironically, the WE postpay and AE semi-postpay phones allowed these free calls all along, and did not require the expensive coin trunk equipment in the central office required for prepay.

[mentalstampede]

Here's a few shots of an AE120 series still in operation that I took today. When Windstream took over from Alltel several years ago they didn't bother to do any major rebranding; they just stuck a few paper stickers on over the Alltel logos.

As best I can tell though, this phone behaves like a real honest-to-god dumb paystation.

[xhausted110]

and, for long distance calls in the USA from the late 70's onward, we used a system called ACTS or Automated Coin Toll System that would come on after dialing a long distance number and request the amount of money for the next 3 minutes or so, and then come on every 3 minutes and request more. the payphone would put out 1700 and 2200 hertz combined, one burst for a nickel, two for a dime, and 5 fast ones for a quarter. the ACTS would be listening for the tones.

[dsk]

This sounds more and more understandable 

dsk

[dsk]

Thank you all of you. 
I got it working! Of course I did not think about everything at first attempt to make a controller, but now I cant fool it anymore. During this process, I did some observations, and had to think a lot how to solve one problem, and of course, the solution was simple, just making a relay remain in its position not only by timer, but a memory contact too.
If the tel-co has done as I did, you may call, and when the called party hangs up, you wait pretty long, e.g. one minute, and then hangs up, and your money are returned. 

dsk