Some thoughts on the Payphone Hack

Talk about the videos and projects (SIM reader, payphones...)

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kd1s
 
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Some thoughts on the Payphone Hack

Post by kd1s »

I really enjoyed your payphone hacking at citizenengineer.com

What I'm curious about is why you felt it necessary to stuff the control electronics in the phone? Bell System controlled these with nothing but tip/ring and ground. It would be possible to make an external device that way you don't have to mess with it to change batteries, etc. Just empty the coin box every now and again.

But I'm glad you linked all the BSP's and other relevant info. Can't wait to see the schematics for this.

I might do a slight re-engineer based on the Arduino platform, seems it's got enough IO ports to make a pretty nice controller for a payphone. I describe the ATMega 168 based Arduino as a device that encapsulates the electronic functionality and lets you use software to manipulate it.

What I'm aiming for is implementing a device that does real 'supervision'. By that I mean that it offers Dial Tone First but requires deposit to connect. Plus I can have it do timed, etc. And with supervision I can also interpret dialed digits and do rating info to ask for more money.

I do like the hack to make the microphone active for a bypass device though.

If I do tackle this (I have to get a 1C payphone first!) I'll post it on the make flickr set.


Kudos on the project though.

adafruit
 
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Post by adafruit »

simulating a bell phone line would require an asterisk box, + and - 130V and all of the control circuitry. plus the phone didnt have the totalizer

I prefer $20 projects that dont include line voltages, dont you?

kd1s
 
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Joined: Mon Jul 28, 2008 2:35 pm

Cheap stuff

Post by kd1s »

Yes, I know. But sometimes you want to do it right. I can figure out how to zap 130V onto the line using a relay for that matter, no need for an Asterisk box at all.

In essence, I'd be building a COCOT style phone. Speaking of which, be careful on Ebay since some of those phones are COCOT and not default Bell style.

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Franklin97355
 
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Post by Franklin97355 »

kd1s, you could write up your design and post it here. I'm sure some of us would be interested.

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