Mystery signal blocking Ottawa door devices

Mystery signal blocking Ottawa door devices

Last Updated Fri, 04 Nov 2005 09:37:24 EST
CBC News

Many automatic garage doors in Ottawa have suddenly, and strangely, stopped working, due to a powerful radio signal that appears to be interfering with the remote controls that open them.

J.P. Cleroux of Ram Overhead Door Systems says the phenomenon began last weekend.

"It affects a 25-mile radius. That´s huge," said Cleroux.

Angolan Ambassador Miguel Puna´s operation is one of those affected by the problem. He can no longer open his embassy´s electronic gate.

"Not only in this gate, but even other gates, we are having a lot of problems," said Puna. "This could cause security concerns."

Two companies that have plotted the reported problems on maps say they appear to cluster in the Byward Market area just east of Parliament Hill, and a corridor leading southeast from there.

The Door Doctor has received more than 100 calls from irate customers who can´t operate their doors using the usual remotes.

The company installs and services Liftmasters, the most popular door opener in North America, which operates by radio frequency.

The signal is transmitted on the 390-megahertz band, which is used by virtually all garage door openers on the continent.

That´s the same frequency used by the U.S. military´s new state-of-the-art Land Mobile Radio System.

Cleroux said operators have already been warned of this phenomenon by service updates from U.S. manufacturers, who started seeing the same problem around military bases last summer. The strong radio signals on the 390-megahertz band simply overpower the garage door openers.

One technician likened it to a whisper competing with a yell.

"From what we hear, it is the American Embassy that´s operating on 390, and they´re the only ones who can block it. But I´m not 100 per cent sure, because we´re all kind of up in the air until we know exactly what´s going on," said Cleroux.

The U.S. Embassy denies any transmissions on that frequency. So does the Canadian military.