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    Kirt Blattenberger,


RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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Remote Garage Door Openers Stop Working in Neighborhood - RF Cafe Forums

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Kirt Blattenberger
 Post subject: Remote Garage Door Openers Stop Working in Neighborhood
Posted: Tue Jan 13, 2009 4:36 pm 
Site Admin
User avatar

Joined: Sun Aug 03, 2003 2:02 pm

Posts: 676

Location: Erie, PA


I just posted an interesting video on the RF Cafe homepage about a community in Virginia where most of the garage door opener remotes stopped working at the same time - around Christmas Eve. Unless there is a Y2008XMAS bug in the systems, then it is doubtful that there is a systemic problem involved. Besides, not all of the openers are made by the same manufacturer nor were they all installed by the same company.

The locals tried to blame the nearby military base, but the spokesman denied any responsibility, and I believe it. Any interferer powerful enough to caused widespread failure of the garage door openers would almost certainly manifest itself in other very noticeable ways.

My guess is that someone attempt a mass hijacking of the garage door opener codes. I have read of drive-by schemes where a person is successful at running through codes fast enough to lock in. The only thing that might disqualify that possibility is some of the remote controllers supposedly will work while within the confines of the garage.

There really was not a lot to go on in the TV report, and I have not seen a follow-up report on what, if anything , was discovered to be the cause.

Have you got any theories, or ever heard of a similar occurrence?


- Kirt Blattenberger :smt024

RF Cafe Progenitor & Webmaster

 Post subject: RE garage door openers
Posted: Tue Jan 13, 2009 5:23 pm 

Joined: Tue Jan 13, 2009 5:01 pm

Posts: 1

Location: Toronto ON Canada

Yes, I've heard of this before. A few years ago the US military was developing a new radio system that works at about 390 MHz, around the same freq as the door openers. They were doing some testing in I believe Florida when locals started complaining that their doors stopped working. After a while, the problem disappeared. The military said "no, not us causing it". A few months later it started happening somewhere out west. Again after numerous complaints the problem disappeared and the military said no not us. A few months after that, is started happening up in Ottawa, Canada. Before anyone got out to investigate, some reporter who remembered hearing what happened down in Florida, called up the US embassy to ask if they were testing a new radio system. They said no but then the problem went away. I'm sure if you do a google, you'll find something like http://www.homelandstupidity.us/2006/12 ... r-openers/

Kirt Blattenberger
 Post subject: More evidence
Posted: Tue Jan 13, 2009 11:07 pm 
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Joined: Sun Aug 03, 2003 2:02 pm

Posts: 676

Location: Erie, PA

Thanks to Dave Rickmers for e-mailing this information:

PUBLIC NOTICE Federal Communications Commission 445 12 th St., S. W. Washington, D. C. 20554 News Media Information 202 / 418- 0500 Internet: http:// www. fcc. gov TTY: 1- 888- 835- 5322

PRESS CONTACT: DA 05- 424 Bruce Romano: 202- 418- 2124 February 15, 2005

Consumers May Experience Interference To Their Garage Door Opener Controls Near Military Bases

Consumers near certain military installations have recently experienced interference to their garage door opener controls that may reduce the operating distance or cause the device to stop operating. This public notice is issued to explain the cause of the interference and the steps being taken to alleviate this problem. The vast majority of consumers will not experience any interference to their garage door opener controls.

Garage door openers operate, legally under Part 15 of the Commissions rules, at very low power on an “unlicensed basis,” and have been permitted to operate on frequencies that have been reserved for the federal government since WWII for air/ ground communications systems, but received limited use by the government for many years. As unlicensed devices, there is no right to protection from interference. However, because of this limited use, the risk of interference was similarly limited, so manufacturers of garage door openers chose these frequencies for their transmit and receive devices. In response to the increased needs of homeland security, the Department of Defense now must make more use of these frequencies to deploy new mobile radio systems on and around certain military bases.

Some consumers near these bases may experience interference to their garage door openers that can reduce operating range or cause the remote control to cease functioning. This interference will not cause the garage doors to open or close on their own. Inside the garage, wall- mounted push buttons will not be affected by any interference that might occur, and will continue to operate normally.

It is not possible to predict in advance which specific users or locations near military bases may experience interference, because of the variety of technical characteristics of garage door controls and configuration of the mobile radio systems. The Department of Defense is working with the National Telecommunications and Information Administration to make reasonable effort consistent with their mission requirements, and the Federal Communications Commission is working with the garage door opener industry to make every effort on their part, to minimize the impact to consumers.

For security reasons, the Department of Defense cannot make information broadly available in advance as to the deployment of the new mobile radio systems. Individual base commanders may make some information available to their local communities when appropriate.

Garage door opener manufacturers stand ready to help consumers resolve any interference to their systems, including, in some cases, making available for purchase, a replacement transmitter and receiver that operate on a different frequency that is not used by the new mobile radio systems.

Consumers experiencing interference should contact the manufacturer of the door opener control or their local installer for information on available immediate solutions.

For further information on this Public Notice, please contact the FCC Call Center at 1- 888- CALL- FCC (1- 888- 225- 5322).

Dave Rickmers


RF Technician

+1 661 705 3700


- Kirt Blattenberger :smt024

RF Cafe Progenitor & Webmaster

 Post subject:
Posted: Fri Jan 16, 2009 3:40 pm 
User avatar

Joined: Mon Nov 24, 2008 2:28 pm

Posts: 2

I was only aware of the interference occurring in the 390mHz range when the military made a switch to the 390mHz range for a new trunked radio system, the Land Mobile Radio System (LMRS). To solve the problem, newly made garage door systems now operate at 315mHz.

1st, i would make sure this guy doesn't live in the area... (biff44)


But seriously,

Next, I would consider possible interference from a nearby UHF SATCOM system.

Posted  11/12/2012

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