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Back to Home Page   01/04/03

This note tells how the Te1eZapper™ device stops telemarketers - and shows you how you can accomplish the same thing for free by using your answering machine or voice mail.

Telemarketing Scheme - how it works

Telemarketers use "Predictive Dialer" computers (PD) which call all the numbers it can until someone picks up.

Lets say a PD calls your number. You answer. You may notice there is a slight delay and the line appears dead just after you answered. Their computer is listening for a short burst of audio, your "HELLO", followed by a period of silence. With this heard, it will log your phone number as valid and transfer the call to a telemarketer. That is the reason for the delay before someone comes on the line.

If you have an answering machine, the PD hears your recorded message, then it will disconnect, but it will remember your phone number as a possible target for a future call.

In all of the above situations the computer remembers your number and the telemarketing company may even sell your number to other marketing companies.

How the Te1eZapper™ - and you - can "beat" the Telemarketer's PD

The PD also listens for Special Information Tones - a series of three tones you have probably heard when you dialed a number "not in service". When a PD hears the Special Information Tones, it will usually conclude the number is invalid, end the call, and drop you from their list - never to call you back.

Here is how YOU can do it for free.

MAC users, download Special Information Tones "sound" file from here. (Decode and unstuff with Stuffit Expander 4.0 or higher.)

PC users, download Special Information Tones ".wav" file from here. (You may need to right click and "save as" in order to save the file to a convenient folder for future use)

Play the Special Information Tones on your computer's speaker using your favorite sound package (Mac users, just double click on the sound file) and record it at the beginning of your outgoing message -  just before your record your greeting on your answering machine or voice mail.

The next time you get a call, let your answering machine answer it first. Set it to answer on the first ring if you like.  Most PDs will be defeated - however, a real human will hear your message - then you can either pick up, or let it be recorded.