Programmable call signal accessory for telephone handset

摘要

The call signal accessory acts as a sound effect device, which is programmed by the user, e.g. via an input keyboard, to deliver a required noise, in place of the standard telephone ringing signal. The accessory is provided as a separate unit, or as a circuit board incorporated within the telephone handset and provides suppression of the normal ringing tone for replacement by the stored information representing the required sound effect.