LED Lights and Garage Door Opener???
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From: Hammy on 13 Apr 2010 20:14 On Tue, 13 Apr 2010 16:35:48 -0700, dplatt(a)radagast.org (Dave Platt) wrote: >I found that the remote-control fob for my car would not work at all >reliably in a local mall's parking lot. Sniffing around with a >hand-held receiver led me to a local Chinese restaurant, which uses a >wireless order-taking system that operates near 433.920 MHz... it's >not Part 15 certified, and as I read Part 15 it's operating in a way >which is quite illegal (tranmissions are much too frequent and >probably too powerful). This happens to me in parking lots as well. I just assumed that it was the RF from the cameras that the business had installed outside swamping my little FOB.
From: Sjouke Burry on 13 Apr 2010 21:38 mrjb1929 wrote: > This may not be appropriate for this site or this section of the site so > forgive me in advance if it doesn't belong here. We have a unique problem > that for the life of my electronics background, doesn't make sense but its > real and strange at the same time... and it's driving us bonkers! > > I have two garage door openers as I have two separate garage doors. The > remotes mysteriously do not work sometimes.... BOTH of them. Our > alternatives are to unlock the house front door and go through the house to > the garage and push the manual button. It doesn't matter which car, or > remote we use, they all work or don't work at the same time (with either > door). > > So we were thinking it was rather odd, but both garage door openers are > failing at the same time. Or something worse. > > Then I realized last night that the problems occur mostly at night or > specifically between dusk and dawn. Around the time that my landscape > lighting comes on. The system has been in use for a couple of years but > just recently I replaced all of the quartz hallogen bulbs with LED to > conserve energy and cut down on bulb replacement. All of the bulbs were > purchased over the internet from a variety of sources (ebay). Some of the > spot lights are up to 6 watts of consumed powere so I suspect there is some > circuitry involved internally. BUT it appears that once I've swapped out > all of the bulbs and the system comes on at dusk, the garage door opener > remotes just do not want to work. Freaky - almost like the aluminum foil > hat type of thing. Can anyone explain this to me or am I thinking > something that just can't happen this way. > > Any advice would help - even those that think I must be smoking something > (I'm not... but hey... it's still advice), Some of those lights have a very cheap switching supply system, merrily transmitting a broad spectrum of radio waves, blocking your transmitter. I see two options, one, to trace-down and/or replace lights, another is to increase the antenna quality of the receivers, by using a parabolic reflector behind the antennas, or give the antennas sideways shielding, or both. Those transmitters are very low-power, and can easily be overruled by interference.
From: Dave Platt on 13 Apr 2010 21:13 In article <322as51u5bbo6mddcp2d1rtd936kpsrm1s(a)4ax.com>, Hammy <spam(a)spam.com> wrote: >>I found that the remote-control fob for my car would not work at all >>reliably in a local mall's parking lot. Sniffing around with a >>hand-held receiver led me to a local Chinese restaurant, which uses a >>wireless order-taking system that operates near 433.920 MHz... it's >>not Part 15 certified, and as I read Part 15 it's operating in a way >>which is quite illegal (tranmissions are much too frequent and >>probably too powerful). > >This happens to me in parking lots as well. I just assumed that it was >the RF from the cameras that the business had installed outside >swamping my little FOB. Entirely possible, I suppose. As I read it, Part 15 intentional-radiator transmissions in the 433.920 MHz range are supposed to be both brief, and occasonal... continuous transmission isn't allowed. A camera would probably be a serious violator, as it would likely be transmitting a large fraction of the time (perhaps continuously). In the case of the restaurant system I found, it has a "polling" behavior - the base station sends out an inquiry transmission several times per second, and any hand-held order-taking terminal with data to send will respond. On an FM or SSB receiver, it puts out a distinctive "pokka pokka pokka" sound, with two or three reps per second. The brand name? "Pokky" :-) -- Dave Platt <dplatt(a)radagast.org> AE6EO Friends of 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!
From: PeterD on 14 Apr 2010 08:31 On Tue, 13 Apr 2010 17:13:16 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Tue, 13 Apr 2010 19:15:30 -0400, Spehro Pefhany ><speffSNIP(a)interlogDOTyou.knowwhat> wrote: > > >Good grief, I've been having the same erratic problem: the garage door >will go up but won't close. I overhauled all the mechanics, cleaned >the limit switches, tweaked the big nasty dangerous spring, all that. >It appears to be a control problem, not a mechanical one. And after a >while it started working again. The receiver/motor box is straddled by >two light sockets on the ceiling, with CFs, drived from a motion >sensor. The bulbs inside the Genie housing are still incendescents. > >Next time it acts up, I'll try incandescents for the ceiling lights. > >John > And sweat the day when you can't get incandescent light bulbs any more because you've been told that they are too inefficient! I'm sure we're going to see a sharp rise in residential fires in the next 10 years, too... Mostly due to cheap chinese CFL lamps failing when used in locations that are totally inappropriate, a move forced by those who "think" they know best for everyone.
From: John Larkin on 14 Apr 2010 10:04
On Wed, 14 Apr 2010 08:31:44 -0400, PeterD <peter2(a)hipson.net> wrote: >On Tue, 13 Apr 2010 17:13:16 -0700, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Tue, 13 Apr 2010 19:15:30 -0400, Spehro Pefhany >><speffSNIP(a)interlogDOTyou.knowwhat> wrote: >> >> >>Good grief, I've been having the same erratic problem: the garage door >>will go up but won't close. I overhauled all the mechanics, cleaned >>the limit switches, tweaked the big nasty dangerous spring, all that. >>It appears to be a control problem, not a mechanical one. And after a >>while it started working again. The receiver/motor box is straddled by >>two light sockets on the ceiling, with CFs, drived from a motion >>sensor. The bulbs inside the Genie housing are still incendescents. >> >>Next time it acts up, I'll try incandescents for the ceiling lights. >> >>John >> > >And sweat the day when you can't get incandescent light bulbs any more >because you've been told that they are too inefficient! I'm goint to order a few cases of them, a lifetime supply, before they become illegal. I suspect there will always be an ebay black market, too. CFs don't work in cold locations, and most can't be dimmed, and most won't work with 2-wire motion sensors. > >I'm sure we're going to see a sharp rise in residential fires in the >next 10 years, too... Mostly due to cheap chinese CFL lamps failing >when used in locations that are totally inappropriate, a move forced >by those who "think" they know best for everyone. I recently replaced one that had failed after a few months. As I was climbing down off the last rung of the ladder, the *new* one failed. I eliminated the timer to all the lights in our stairwells at work, so they stay on all the time. The CFs last much longer that way. The good ones last for years at 100% duty cycle. The bad ones get culled out in a few weeks or months. Next we'll have expensive LED bulbs that "last up to 100,000 hours" with crappy electronics. Nearly all the green LED traffic lights in San Francisco have failed, in interesting patterns, and had to be replaced. Only the greens, for some reason. John |