Re-Wiring a Pay Phone to accept coins

[mwplefty]

Is it possible to re-wire a vintage payphone to only "call out" if, for example, $0.10 is added? In other words, is it possible to make it work like it did when it was in operation?

[Phonesrfun]

It depends on whether the coin track, the coin chute, the coin trip mechanism and the coin relay are still there.  Many times some of those components have been stripped out of an old pay phone to make them work on a regular phone line.

If all the coin related components are there, then you need to either build or buy a pay phone coin simulator.  You need an electronic simulator because a regular phone line is not equipped the same as the old lines that used to be connected to the pay phone.

To build a controller requires some good skills at building and soldering electronic devices, and is not for someone who has never tackled that sort of project.  They can be bought too, but I don't know what they might cost.  Perhaps $50, perhaps $100.  something like that.  Then, wiring it in to the pay phone uses several wires.

[DavePEI]

One of the best Payphone controllers available:

Ebay 300714491356

or go to Stan's items:

http://www.ebay.ca/sch/gray-western/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1

A controller built by gray-western (Stan Schrier) - once the auction has run out, typically he will post another, and you would be able to search his member name and find new listings. As soon as this one sells, he typically lists another. It will work with just about any phone with an intact pay mechanism. Stan is known by some as the "Guru" of payphones.

So long as your phone''s pay mech. is in good shape, it will return it to "like original" operation with coins.

Dave

[Phonesrfun]

I have been pretty impressed with Stan's device.  He has gone to some great lengths to make it nice and easier for a non- phone person to install.  It still takes a bit of wiring to get it wired up correctly.  I saw his video demonstration and it looks great.

[gpo706]

There's a video explanatory available for retroing at "citizen engineer" AFAIK.

[johnnyjt]

Yes, Stan did a awesome job with his Coin Controller.
It's the only way to go with a 3 Slot.

JohnnyJT   
South Philly 

[gpo706]

http://www.citizenengineer.com/

about half way in, get your soldering irons out folks...

[DavePEI]

http://www.citizenengineer.com/

about half way in, get your soldering irons out folks...

That only shows you how to get around a missing totalizer - not how to wire the phone to accept coins. If the totalizer is missing, you must jumper it to get the phone to do anything at all. This only allows you to use the phone as a home phone, but not to accept coins.

Dave

[dsk]

Interesting thread, how did it actually work? Any hints about how I could reed me up on this?

Here in Norway the very first collected just one coin on polarity reversal, and that's it. (only local calls, or manual collecting by the operator on long distance)

Later at least one of the systems used in-band signalling. a beep of 12 or 16 k Hz was used both ways.

When I served we had a coin collector using some 16 kHz. When we switched lines with the internal telephone, we could just keep on calling. Did only use this the last 2 weeks so we got away with it

dsk

[dsk]

It seems impossible to get a Norwegian coin phone from pre transistor era, so if I want one, I have to go for a foreign one.
No I really need help to a cure this disease I want one, just to make it work. And I know when I've solved it I will actually have no need of it.  It will probably hang on a wall, and just be something I want use, and will be some strange foreign thing. My other foreign phones are at least used, but a pay-phone!
I'm actually quite sure I could make it work, and with some fetling it could even collect coins for each 16 khz signal sent from the exchange. (You may still pay for that extra signal)

This page is quite informative: http://oldphoneguy.net/images/MPPwk.pdf

dsk

[James]

I just finished building a coin relay controller that I designed myself. I've included the schematic of it in case anyone' s interested. I'm still working on a PDF file that explains how it works, how to build it, etc.

[dsk]

Great!
Do I understand this right.
When going off hook relay one sends signal to the micro-controller. (depending on programming) The led may change, but no relays operates, When hanging up, the coin relay gets a positive or negative (relay 2 ) signal  (relay 1) depending on e.g. time and collects or return the coin. 

The only reason I see for letting Relay 1 disconnect line when sending signal to coin relay is to prevent spikes sent out on the line.

dsk

[James]

It's actually relay 3 that acts as a line sense relay to tell the microcontroller when the payphone is on or off hook. And you're right about the reason for disconnecting the tip side of the phone line. It's to prevent noise generated by the coin relay from going through the tip side of the phone line. In most cases it's not really necessary but my payphone has a 101A induction coil but it really should have a 101B with the coin relay connected to the center tap of the primary coil. Mine is connected to the R terminal of the payphone which is also where the tip side of the line cord is connected.

[James]

Ok, I have to admit now that I don't know how to get the controller to tell the difference between an on/off hook state and a set of dial pulses. I guess the easiest way around that would be to scrap the line sense relay and, instead, add a separate, isolated switch on the switch-hook. the wires from that switch could go to the black and white wires on the rj14 jack.

I wish I could figure out how to do this without any payphone modification but I'm not that great at programming.

I attached the programming code that I came up with. If anyone can help make this work, it would be much appreciated.

[James]

Latest update. I made a change to the circuit to include hardware debounce. Hopefully this will filter out the dial pulsing. I haven't tested this yet so I don't know, right now,  if this will work. I attached a graphic that highlights the change.