TeleZapper

The TeleZapper is a device designed to reduce the number of telemarketing-related phone calls a household receives by imitating the tone signal normally played by a phone company to indicate a line has been disconnected. The Telezapper was created by Privacy Technologies, Inc, a wholly owned subsidiary of Royal Appliance Mfg. Co.

Telemarketing companies typically use predictive dialers to place many calls simultaneously. When the equipment detects that someone has answered one of the many calls it has made, it quickly transfers that call to an available agent. Unanswered calls, or numbers that are disconnected, are not transferred to agents and the call is terminated automatically.

In this way, the agent is spared the time of dialing a call and waiting for an answer, and can simply speak to waiting calls that have been already set up. Additionally, if a number is determined to be disconnected, the equipment will usually mark that number as such and will not dial it again or as often.

The TeleZapper is an appliance that plugs into a consumer telephone line. On detecting a ring and answer of any phone on the line, the Telezapper will immediately play a sequence of Special information tones or "SIT": one of eight internationally standardized signals that indicate a call cannot be completed. Typically the "Intercept" or "IC" SIT is used, indicating the number called has been disconnected or changed.

IC SIT

Intercept tone played by The TeleZapper (2 times)