Wednesday, April 15, 2009

Jam.

This is coolbert:

Here, today, from South Africa:

"News - South Africa: Mystery signal leaves suburb in a jam"

"A signal-jamming problem has left thousands of residents in the Blairgowrie, Randburg, area battling to work the remote control devices that operate their gates, garage doors, car alarms and security systems."

"Independent Communications Authority of South Africa (Icasa) spokesperson Sekgoela Sekgoela said they had suspicions about what was causing the signal jam but would be able to confirm the source only after further inquiries."

"Sekgoela said the interference was on a frequency reserved for industrial, scientific and medical use. It is exempt from licence requirements but still needs Icasa approval."

And here, from the U.S., dated 2004:

"Military Jams Garage Doors Openers"

WASHINGTON, Dec. 6, 2004

"Coming soon to dozens of military bases [U.S.] around the country: radio signals strong enough to jam nearby garage-door openers."

"Between now and 2008, the military [U.S.] is supplying a new radio system to roughly 125 bases that uses the same frequency as the one relied upon by more than 90 percent of the remotely operated openers, Pentagon and industry officials say."

"The garage-door opener frequency at issue -- 390 megahertz -- has belonged to the military [U.S.] since around 1950."

"U.S. law allows low-power electronic devices to operate on military frequencies if they don't cause interference. It was a good frequency for garage-door openers because transmissions can penetrate the doors"

This is the same phenomenon at work? Military transmitters, causing interference to garage door openers and other remotely operated devices?

In the case of the U.S. - - the frequency is around 390 MHZ. IN the case of South Africa, the frequency is around 433 MHZ. So not the same. And that frequency in the U.S. HAS ALWAYS BEEN RESERVED FOR THE MILITARY. NOT SO IN SOUTH AFRICA!

coolbert.

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