This is a replacement for the $50 Telezapper. Working very similarly to the Privacy Box above, it plays one of the special information tones (SIT) - that is the bee-bee-BEEP tones you hear before a US not-in-service recording. The telemarketing dialer hears the tone, assumes the line is out of service, and your number gets taken off their list.


Great, now there are only 9,999 telemarketers lined up to interrupt you screwing your girlfriend.


The Telezapper Box is not really a box, it's just the idea of putting that same tone in the outgoing message of your answering machine. That might actually work, as long as your answering machine isn't such total crap that it actually distorts the tone to the point where the dialer cannot hear it. Some answering machines really do suck that badly.


Early in 2003, a new predictive dialer called DirectQuest was introduced that gets its call progress information from a separate digital channel that you, as the telemarketer's mark, don't have access to. As DirectQuest and its inevitable imitators gain a foothold in the telemarketing industry, the Telezapper will gradually become less and less useful. In addition, some telemarketers are aware of the Telezapper and have disabled the call progress detection in their dialers. Why they would do this is baffling as the presence of a fake SIT tone should be a dead giveaway that no matter what the telemarketer is selling, you don't want it. Even minimum-wage telemarketing droids aren't free, and that affects the bottom line which is the only thing telemarketers give a hump about.

Plausibility

Very feasible, in fact I'm amazed the Telezapper device is still being sold when people can get the tones for free on the web.

Obsolescence

On its way out, thanks to modified practices by telemarketers, and predictive dialers such as DirectQuest(tm) that get call progress information from a separate, digital line provided by the telco instead of from tones you can spoof. Eventually the company that makes Telezappers may find itself forced to resort to telemarketing to sell them...

Skill

Very little, but best results involve hacking some kind of direct connection to the microphone of the answering machine, so skill needed varies depending on how good you want the tone to sound.

Risks

None, it's legal (althought the DMA would certainly like to make you a criminal for trying to avoid them...)


Description from The Fixers Box Review @ ArtofHacking.com