Garage door openers are under assault by military radios, and it?s no ones
fault. For over half a century, one of the radio frequencies reserved for
military use in the United States has been the 380 to 400 megahertz band (FM
radio, for example, broadcasts on the 88 to 108 megahertz frequencies). For
about two decades, manufacturers of garage door openers were allowed to use the
390 megahertz frequency, because the openers were very short range (low power)
and unlikely to interfere with military radios (or vice versa). But a new
generation of military radios has changed all that, by sending out powerful 390
megahertz signals.
The problem was first noted last Fall, as new radio
systems, using the 390 megahertz frequency, were installed on military bases. By
2008, some 125 bases will be using the new radio system. The Department of
Defense says that the new radios only make garage door remote control systems
inoperable. But thousands of users report that they have seen the garage doors
open and close by themselves. Since the garage door system manufacturers are
using the 390 megahertz frequency unofficially (but with the knowledge of the
government), they will have to change their equipment to use another frequency.
That could cost up to a hundred dollars, or more, per system. Garage opener
manufacturers, based on reports from their repair technicians, believe that the
new radios interfere with garage door controllers up to 80 kilometers from
military bases. That?s over 50 million garage door systems.
There will be
more problems like this, as more wireless equipment comes into use, and the
military makes more use of frequencies they have long ?owned.? It's not a new
problem, and was first noted on a large scale during the 1991 Gulf War. Here,
there was a large concentration of military equipment form all the American
military services, and foreign armed forces as well. There were several
unexpected incidents where frequencies collided in unexpected ways. There was
some of this again in 2003 in Iraq. There will be more, and some of it will be
deadly.
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