Block specific incomming call numbers on your home phone?

[neazoi]

Hello,
There are some annoying advertizing companies that keep calling my friend's home phone rudely. Hopefully their calling numbers are known and are always the same. His phone provider cannot block specific incomming call numbers, so I was thinking of a local way.

Is there any microcontroller project out there that will be able to identify the caller number (maybe a list of 2-3 numbers) and automatically and instantaneously hang on and then imediatelly off the phone, so that it appears to the caller that someone has answered the phone and imediatelly terminated the call?

I have not found such a project on the net but maybe I am not looking for the right thing.

 

[wp100]

Hello,
There are some annoying advertizing companies that keep calling my friend's home phone rudely. Hopefully their calling numbers are known and are always the same. His phone provider cannot block specific incomming call numbers, so I was thinking of a local way.

Is there any microcontroller project out there that will be able to identify the caller number (maybe a list of 2-3 numbers) and automatically and instantaneously hang on and then imediatelly off the phone, so that it appears to the caller that someone has answered the phone and imediatelly terminated the call?

I have not found such a project on the net but maybe I am not looking for the right thing.

Hi,

Fitting your own diy equipment to the telephone system can be illegal in some countries.

There are various ready made call blockers though no idea if these would be compatible with your telephone system.
**broken link removed**

Again here in the UK we have free services who will remove your number from the dialing lists circulated to these 'cold' calling companies.

 

[betwixt]

Such devices are available on the market but their usage depends on your Telco. The system used to identify the caller varies from one company to another so there is no universal way to do it. I'm not sure which system your country uses, in the UK we use a line polarity reversal followed by a pilot tone then a burst of V.23 FSK data, in some other countries the data is sent between the first and second ring voltage bursts. The format of the data varies too.

There may be legal implications of connecting home-made equipment to the line due to potential safety issues but building something sensibly with isolated circuitry should be fairly easy to do.

Brian.

 

[bigdogguru]

There are Caller ID boxes available which can block specific caller numbers as well as block unidentified caller numbers.

Sentry Call Blocker

You'll need to search for devices specific to your country and telco.

If you feel up to building a Caller ID box, blocking specific calls is secondary.


BigDog

 

[neazoi]

Thank you all for your replies!
I have just noticed that my friend's DECT phone is the Panasonic KX-TG6611 which supports up to 30 incomming calls automatic blocking, so I think this will solve his problem.
However it has been very usefull to now how this works.