A Mini Payphone Controller in order to use coins in three slot pay telephones

Posted on Feb 6, 2014

An awful thing happened a few weeks ago. I ran out of telephones to restore. All my payphone projects were finished. They were lined up on shelves doing what antique telephones do best - collect dust. I also wanted to write about a special project for the New Year. Something that would be out of the ordinary, creative, useful, and unique - and cou

A Mini Payphone Controller in order to use coins in three slot pay telephones
Click here to download the full size of the above Circuit.

ld actually be used and enjoyed. 2- The input of the controller would plug into a standard subscriber line. The output would mimic the operation of a payphone line circa 1950`s, including the timing of all the functions. 4- It had to operate every prepay model made by Western, Northern or Automatic Electric. Regardless if it was two piece, handset, single coil relay, double coil relay, rotary or Touch Tone. 5- It would collect or return the initial deposit on hang-up, controlled by a timing circuit. Called party supervision no longer existed and getting involved with SIT and voice cadence recognition for a hobby project was out of the question. After six months of circuit design I ended up with a device that was expensive and complex to build. Fortunately at that time I had the facility around me to do the job. Unfortunately that facility and most of my vendors from that time no longer exist. 8- To meet the first three criteria a coin must be deposited in order to answer an incoming call. The coin will be treated like an initial deposit for an outgoing call when the phone is hung up. 12-The main purpose of this controller is to animate the payphone`s coin mechanism. Really making the phone into - A PAY PHONE! Due to the characteristics of the double coil coin relay used in early model payphones, it`s not possible to power them from the phone line. You can however replace the old style hopper and double coil relay with a...

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    Simple Amplified Field Strength Meter Circuit
    simple common emitter amplifier
    CSC231 Homework
    Long Range FM Transmitter
    servo motor tester circuit
    Esposito Wang
    Battery operated mini night lamp
    Some interesting Projects
    16F54 fickle!
    Toggle Switch No.1 - Cmos 4013