My aunt, who lives in So. Calif., along with two close neighbors, is
suddenly having problems with garage door openers. Won't open. Stop
part way down, etc. I haven't heard of amateur radio having an effect
on modern garage door remote receivers. How about BPL? Don't know if
it can effect things in the 900 Mhz region, but thought I would ask if
anyone else has seen this.

Dick - W6CCD

My aunt, who lives in So. Calif., along with two close neighbors, is
suddenly having problems with garage door openers. Won't open. Stop
part way down, etc. I haven't heard of amateur radio having an effect
on modern garage door remote receivers. How about BPL? Don't know if
it can effect things in the 900 Mhz region, but thought I would ask if
anyone else has seen this.


I'd be surprised at BPL causing this, given its low signal strength,
but I suppose something to consider. I recall hearing of some new
military "secure" communications system having such effect on garage
doors.... but occurs over many square miles, not just one small local.
The problem I read about was back in the South East, I think.

I guess if just a couple houses next to each other are having issues,
one would begin to look in that vicinity.


Ed K7AAT

In article ,
Dick LeadWinger wrote:

My aunt, who lives in So. Calif., along with two close neighbors, is
suddenly having problems with garage door openers. Won't open. Stop
part way down, etc. I haven't heard of amateur radio having an effect
on modern garage door remote receivers. How about BPL? Don't know if
it can effect things in the 900 Mhz region, but thought I would ask if
anyone else has seen this.

BPL would not, I think, as all of the BPL systems I've heard of use HF
and lowband VHF on the power lines (and some use 2.4 gig or other
ISM-band frequencies for uplink to the ISP).

I have heard of people having serious problems with Part 15 devices
which operate in the 433 MHz region (as many garage door openers do).
The primary user of this slice of spectrum is the U.S. government...
it's allocated for radiolocation (radar) and there may be other
government communications in that band as well, I suspect. Some
months ago there were reports of people living around certain
government air bases and other installations began having
garage-door-opener blackouts, because some new radar systems had gone
into use and were interfering with the Part 15 receivers.

There might be similar problems in the 900 MHz ISM band, I suppose.

A local amateur radio operator transmitting in either the 70 cm or 33
cm amateur band might cause transient overload of a Part 15 receiver
using these frequencies. I'd expect this to be a relatively
short-lived phenomenon, unless somebody's operating a popular repeater
in your neighborhood.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

There have been problems with military use of the 300 MHz band for new
radio systems, but this would not cause the door to work only half way.

Assuming the neighbors problems are coincidental, check the
counterbalance spring for the door. They wear out or break and the
opener does not have enough power to work on irs own. By the way this is
not a DIY project because of safety concerns with the springs and the
repairs can be about $300.

Dick wrote:

My aunt, who lives in So. Calif., along with two close neighbors, is
suddenly having problems with garage door openers. Won't open. Stop
part way down, etc. I haven't heard of amateur radio having an effect
on modern garage door remote receivers. How about BPL? Don't know if
it can effect things in the 900 Mhz region, but thought I would ask if
anyone else has seen this.

Dick - W6CCD



--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

There have been problems with military use of the 300 MHz band for new
radio systems, but this would not cause the door to work only half way.

Assuming the neighbors problems are coincidental, check the
counterbalance spring for the door. They wear out or break and the
opener does not have enough power to work on irs own. By the way this is
not a DIY project because of safety concerns with the springs and the
repairs can be about $300.

Dick wrote:

My aunt, who lives in So. Calif., along with two close neighbors, is
suddenly having problems with garage door openers. Won't open. Stop
part way down, etc. I haven't heard of amateur radio having an effect
on modern garage door remote receivers. How about BPL? Don't know if
it can effect things in the 900 Mhz region, but thought I would ask if
anyone else has seen this.

Dick - W6CCD



--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

In article ,
**THE-RFI-EMI-GUY** wrote:

Assuming the neighbors problems are coincidental, check the
counterbalance spring for the door. They wear out or break and the
opener does not have enough power to work on irs own. By the way this is
not a DIY project because of safety concerns with the springs and the
repairs can be about $300.

Good point!

I recently had a spring break in our 1960-vintage rolling door
setup... the door wouldn't even start to roll up with only one spring
out of two providing proper tension.

The repairman who came out and replaced it, said that he gets a
significant percentage of his business from people who first tried to
do the repair themselves... and decided to call him after they got out
of the hospital. The most common injury seems to be a broken
collar-bone. Those springs are under a *lot* of tension.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

This garage door and opener system are not more than a year old. I
don't know the brand name, but it was not inexpensive. The door does
operate perfectly with the wall button. The service people have been
out and changed out both the receiver and the remotes. Still will not
operate. That's why the serviceman thinks it has to be some kind of
RF interference. Apparently he didn't have the equipment to trace it
out.

For the record, this home is in an older residential area near the
University of California Fullerton. No military installations that I
am aware of. Something at the University or local high school might
be doing it, but the high school is a couple of blocks away, and the
University is about 1/2 mile. If I were near there, I could bring one
of my receivers and trace it down pretty quickly, but I'm 500 miles
away.

Dick

On Thu, 26 Jan 2006 23:54:07 GMT, **THE-RFI-EMI-GUY**
wrote:

There have been problems with military use of the 300 MHz band for new
radio systems, but this would not cause the door to work only half way.

Assuming the neighbors problems are coincidental, check the
counterbalance spring for the door. They wear out or break and the
opener does not have enough power to work on irs own. By the way this is
not a DIY project because of safety concerns with the springs and the
repairs can be about $300.

Dick wrote:

My aunt, who lives in So. Calif., along with two close neighbors, is
suddenly having problems with garage door openers. Won't open. Stop
part way down, etc. I haven't heard of amateur radio having an effect
on modern garage door remote receivers. How about BPL? Don't know if
it can effect things in the 900 Mhz region, but thought I would ask if
anyone else has seen this.

Dick - W6CCD

"Dave Platt" wrote in message
...
In article ,
**THE-RFI-EMI-GUY** wrote:

Assuming the neighbors problems are coincidental, check the
counterbalance spring for the door. They wear out or break and the
opener does not have enough power to work on irs own. By the way this is
not a DIY project because of safety concerns with the springs and the
repairs can be about $300.

Good point!

I recently had a spring break in our 1960-vintage rolling door
setup... the door wouldn't even start to roll up with only one spring
out of two providing proper tension.

The repairman who came out and replaced it, said that he gets a
significant percentage of his business from people who first tried to
do the repair themselves... and decided to call him after they got out
of the hospital. The most common injury seems to be a broken
collar-bone. Those springs are under a *lot* of tension.


A long time ago someone told me about the problems that can be caused by a
garage door spring breaking under tension. There is a simple safety
measure. Get some of the 3/16-inch stranded cable that is commonly sold at
Lowe's, Home Depot, etc. Get four cable clamps. Run a length of cable
through the center of each coil spring, the length of the spring. At each
end, loop the cable through something -- there are usually holes in the door
mounting frame -- and secure with the cable clamps. This way, if the coil
spring snaps, it will not go anywhere because the cable will catch it.
Otherwise, you'll have a big piece of coil spring shooting through the
garage at almost the velocity of a bullet. Trust me, I know.





--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

I once made a service call to Automatic Door in Chicago. They had a
newspaper article on their bulletin board about some unlucky guy who
came home to find his garage door spring unwound. It seems he decided to
fix it himself and while up on the ladder he got his necktie (another
good reason to ban them) caught in the spring as it wound itself up. His
wife tried to cut him down with scissors but was too late..

Dave Platt wrote:

In article ,
**THE-RFI-EMI-GUY** wrote:



Assuming the neighbors problems are coincidental, check the
counterbalance spring for the door. They wear out or break and the
opener does not have enough power to work on irs own. By the way this is
not a DIY project because of safety concerns with the springs and the
repairs can be about $300.



Good point!

I recently had a spring break in our 1960-vintage rolling door
setup... the door wouldn't even start to roll up with only one spring
out of two providing proper tension.

The repairman who came out and replaced it, said that he gets a
significant percentage of his business from people who first tried to
do the repair themselves... and decided to call him after they got out
of the hospital. The most common injury seems to be a broken
collar-bone. Those springs are under a *lot* of tension.




--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

Read the installation manual for the opener. I installed a "Genie" at my
last house. The logic for the wired button and the remote control are
quite different. The door adjusts its speed and torque by learning from
using the wired control. There is a torque sensor which detects
blockage of the door as well. Again read the manual, it could be the
installer does not RTFM!

Dick wrote:

T(snip) The door does
operate perfectly with the wall button. (snip)
Dick




--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P