Advances in telecommunications systems have provided more services to telecommunications users. For example, telecommunications device for the deaf (TDD) and text telephones (TTY), hereinafter both referred to as TTY devices, allow users to communicate with non-speech sound on a telephone network. Such users include those users who cannot hear and those who cannot speak. Another service, such as Prompted Automatic Callback (PAC), provides users with a voice message informing the user that the line they are calling is busy. For example, the PAC system may provide a message that states “the number you have dialed is busy.” The PAC system may also ask the user if the user wishes to invoke an automatic call back feature to automatically call back the number when the line becomes available.
Prior to the development of automatic callback services, TTY users could recognize a busy signal by observing a determined pattern of flashes of a signal strength light of the TTY device that are produced by the busy signal. When a telecommunications provider provides an automatic callback service such as the PAC service, however, the busy signal is replaced with the announcement stating that the line is busy. Absent the busy signal, TTY users may no longer be able to recognize a busy line. The announcement produces intermittent flashes of the TTY signal strength light indicating that words are being spoken and does not produce the patterned flashes of the busy signal. The intermittent flashing light conveys no specific information to the user, thus the TTY user would be unaware that the line is busy.
Thus, there is a need for an improved communications system that can aid a TTY user in identifying a busy condition even when the communications system uses an announcement service such as the PAC service instead of the busy signal.