LEC Phones LEC stands for Local Exchange Company and it means the local phone company in a given area. The following are descriptions of the most common phones used by LECs. The fortress phone is the most basic of all pay phones. The are three main variations of it, the Western Electric model, the GTE model, and the Nortel Centurion. Although the phones look quite different, they all operate the same way.
Fortresses require a special coin line to operate properly.
For local calls, the phone counts up the money until enough has been put in. When a sufficient deposit is made, the pay phone changes its grounding arrangement so that it will pass the coin ground test. After a phone number is dialed, the central office sends an electrical pulse to the pay phone to determine if the call is paid for or not. This is the coin ground test. If the call is paid for, it goes through.