Some 1.5 million people a year receive calls that are not welcome
A device which claims to alleviate the problem of cold calling has been launched by two British inventors.
The TrueCall device acts as a buffer between the phone and the outside world and learns to distinguish between welcome and unwelcome callers.
It is estimated that the British public receive 1.5 billion silent calls and 1.5 million malicious calls each year.
According to a recent Ipsos MORI survey, 70% of UK phone owners say they have been victim of a phone scam.
The most common scam tries to get the receiver to call a premium rate phone line while another - known as vishing or voice phishing - tries to collect personal information over the phone.
Both rely on getting through to speak to a person, which gave inventors and ex-telemarketers Steve Smith and John Price the idea for a blocking device.
"TrueCall is designed to give people control of their landlines," said Mr Price.
"You can bolt the door and close the curtains but your landline is the weak link in your privacy," he said.
The system basically intercepts all calls. If it recognises them as a friend or a member of the user's family - numbers on the so-called star list created by the user - it lets them through as normal.
If the caller's number is on a zap list - numbers of telemarketers or other nuisance callers - the device answers it, and all future calls from that number, with an automated message which means the phone does not ring at all.
If the system doesn't recognise the caller's number, or the caller withholds their number, it asks them who they are, puts them on hold and then rings the user's phone.
The user has the option of taking the call, having the system take a message, or they can reject the call and add the number to the "zap" list.
Users can add callers to their "star" list by pressing the star button on their phone at any point during a call.
In future, there are plans for the device to be able to download a list of blacklisted numbers from a central database, which can be dialled into via a modem inside the box.
This will transmit information about each call that was made, if this is requested by the user.
But there are "legal issues" that need to be resolved before this "telephonic neighbourhood watch" can be put into action, said a spokesman for the company.
COMBATTING NUISANCE CALLS
Phone companies have teams that can advise on nuisance or malicious calls
They may put a trace on your line if you receive a large number
You may also be offered call rejection, but it could reject legitimate calls, for example from overseas
Registering with the Telephone Preference Service makes it illegal for companies to call you for marketing purposes
It takes 28 days for the TPS calling ban to take effect
David Hickson is a veteran campaigner on the issue of silent calls and, was, partly, the inspiration for the system.
"The device is a great idea for people who are bothered by a lot of nuisance calls and want to have a virtual receptionist in their home to manage their calls," he said.
But he doesn't think it alone will solve the problem.
"There is a lot more that Ofcom can do. It has powers but it could use these much more effectively," he said.
Ofcom is tackling the problem and recently fined Barclaycard £50,000 for silent calling thousands of people.
It fined Abbey National earlier in the year and said that other investigations were ongoing or pending.
But, said Mr Hickson, more needs to be done to make sure the technology behind silent calling is used more responsibly.
Some 60% of UK households are signed up to the Telephone Preference Service, set up to reduce the number of nuisance calls received.
But telemarketers are finding new ways of getting around the service with so-called robo-calls which use automated system to deliver millions of pre-recorded messages.
Most silent calls are caused by such systems and it is estimated that the public receive 1.5 billion silent calls per year.
"We welcome anything the industry does on its own initiative to reduce the problem of silent, abandoned or malicious calls," said a spokeswoman for Ofcom.
The TrueCall device is available from the maker's website for £99.99.
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