Anyone use Telezapper?

This telezapper device is supposed to reduce calls from telemarketers. Does anyone use it? I didn’t see much discussion through a search at SDMB.

The Do Not Call list is more effective. And it’s free.

      • It has been discussed, somewhere here (and elsewhere) a while ago–apparently right after the phone is picked up, it plays the 3-note signal that signifies that the number you have called has been disconnected. Automated dialing systems assume the number is disconnected and hang up immediately.
  • You can do the same thing with an ordinary answering machine if you just record the 3-note signal before you say your usual message, but the problem is that this has no way to discriminate between telemarketers and any automated messages you may have wanted to get.

The Do Not Call list worked for us. And is free.

The more modern telemarketers are all using software that depends on the phone company trunking signals (like the ones that do called id) rather than listening for the recorded tones. So the telezapper has no effect on them; the phone company has already signaled to them that yours is a working number. On the other hand, these telezapper tones are probably pretty annoying to any of your friends who try to call you.