| Name | 1A1 Fortress |
| Date | 1965 |
| Manufacturer | Western Electric |
Development of the
| Fortress Style Pay Phones – The More Modern Pay Phone The WE 1A1 single slot dial phone was the first of the Fotress style payphones (the design that was later to become the US standard). “Fortress” is a nickname for the single-slot pay phone developed by the Bell System in the late 1960s. The name now applies to any style of single-slot, coin line controlled pay phone. There are 3 main variations of the “Fortress” pay phone. The original Western Electric model, used only by Bell System companies, the Automatic Electric (GTE) model, used by many independent companies, and the Northern Electric (Nortel) Centurion model, used by Canadian companies and by some USA independent companies. 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 the local rate has been deposited. When a sufficient deposit is made, the pay phone completes a path to ground so that the phone will pass the coin ground test. After a phone number is dialed, the central office conducts the coin ground test, which consists of sending an electrical current to the pay phone and measuring the resistance to ground. If the resistance is infinite, the call is considered unpaid and routed to a recording telling the caller to hang up and pay before dialing again. If the resistance is around 1000Ω or less, the call is considered paid and it is put through. Below- Bruce Springsteen 1978 |
Leave a Reply