Hi All:
To someone new with Single Slot Payphones, it is common for them not to understand what a dumb payphone is, and what a COCOT phone it, and also to understand some phones may have been converted from dumb to COCOT. Both can appear identical as viewed externally.
A dumb phone is a phone whose rates are set by the CO via signalling on the line. This is the simplest explanation I can think of. This would include all 3 stots, and any original 1A, 1B and 1C Western Electric and AE 120a and b phones. These phones if stock, do not require external power. However, these phones can be modified to become COCOT phones, and you will have to determine which they are currently set up as.
COCOT (Customer Owned Coin Operated Telephones) are smart phones. Meaning, they do not require a dedicated payphone line. Rates are set by rate tables contained within the phone itself, and no interactions with the CO is required.
Rate tables set how much is charged for different types of telephone calls and are contained on a ROM or Eprom inside the phone. These are loaded before the phone is originally placed in service.
Many WE and AE single slot phones may have been converted to COCOT by removing the original board from them and replacing the board with COCOT components (Protel, Elcotel, Quortech, etc.).
An untouched dumb single slot is easy to use on a home line. Generally, all that is required is to connect the ring and tip connections of the line to the phone, and they will operate, but of course, not collect coins. Because of this, any coins which may be inserted will gather in the escrow portion of the coin path and jam up since the coin relay doesn't get a signal to dump the coinage in the path. The solution to that is as simple as tying the coin relay in, providing a straight path to either the coin box or to the coin return.
COCOTS are different. In order to use them on a home line, you will have to modify programming in the phone to allow free calls. Many will require external power supplies as well, to provide power for the microprocessor. Later boards generally operate off power from the telephone line. Without getting into a lot of details, in order to use these phones, you will have to have a means of changing the rate tables, and for that, you will require a manual and doing it yourself or have professional programming done. If you have professional programming done, you will tell the programmer how you want to phone to work, and they will call up your phone and load new data into your phone via its built in modem. If you opt to program by hand, it is a painstaking process with information programmed from the touch-tone pad - you will definitely need a manual for the board in the phone is you plan to do this.
It isn't my intent in this message to go further giving modification routines - just to make sure those reading it become aware of the differences.
The easiest phones to convert will be those without microprocessors. Other comments on the differences are encouraged.
Dave
