CFL/ zapper problems
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From: N_Cook on 10 Apr 2010 07:51 Nothing technical in this national newspaper article, anyone been there before ? poor/absent Hamming codes ? mains wiring interference, not IR ? (hallway lamp ref in the full article) http://www.guardian.co.uk/money/2010/apr/10/energy-saving-lightbulbs-virgin- media The strange case of the energy-saving lightbulbs and Virgin Media Got a Virgin set-top box with a mind of its own? And energy-saving lightbulbs? Then you might find there is a surprising connection o Graham Snowdon o The Guardian, Saturday 10 April 2010 Emma Clements was advised to switch bulbs when her TV kept changing channels. If your television or cable equipment seems to have a life of its own, why not get rid of your lightbulbs? It might sound like a joke, but that's the advice Virgin Media gave to Emma and Alistair Clements when their cable TV receiver started behaving oddly. .... continued ... -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://diverse.4mg.com/index.htm
From: Catwatcher on 10 Apr 2010 08:45 Had a similar problem with a dish network box about 2-3 years ago. The CFL was in a floor lamp line-of-sight about eight feet in front of the box. Pressing a key on the remote would yield unexpected results. After several days we correlated the problems with the light (which wasn't used all the time). I suspect the CFL emitted significant IR which confused the receiver in the box. Catwatcher "N_Cook" <diverse(a)tcp.co.uk> wrote in message news:hppolp$qnq$1(a)news.eternal-september.org... > Nothing technical in this national newspaper article, anyone been there > before ? poor/absent Hamming codes ? mains wiring interference, not IR ? > (hallway lamp ref in the full article) > >
From: sparky on 10 Apr 2010 09:39 On Apr 10, 8:45 am, "Catwatcher" <da...(a)alienos.com> wrote: > Had a similar problem with a dish network box about 2-3 years ago. The CFL > was in a floor lamp line-of-sight about eight feet in front of the box. > Pressing a key on the remote would yield unexpected results. After several > days we correlated the problems with the light (which wasn't used all the > time). I suspect the CFL emitted significant IR which confused the receiver > in the box. > > Catwatcher > > "N_Cook" <dive...(a)tcp.co.uk> wrote in message > > news:hppolp$qnq$1(a)news.eternal-september.org... > > > > > Nothing technical in this national newspaper article, anyone been there > > before ? poor/absent Hamming codes ? mains wiring interference, not IR ? > > (hallway lamp ref in the full article)- Hide quoted text - > > - Show quoted text - it is a well known problem ( to some of us anyway ) that CFLs produce massive amounts of IR radiation interference and will create havoc on some remote controls. For some reason not all remotes are affected. This is one of the prices we pay for cheaper lamps.
From: William Sommerwerck on 10 Apr 2010 10:09 > It is well-known that CFLs produce > massive amounts of IR radiation.. Many fluorescent lamps do. I had this problem some years ago with a Sony 8mm VCR. The reason this problem isn't common is because remote-control receivers recognize /specific/ pulse sequences, unique for each manufacturer and product. The probability that a particular fluorescent lamp will emit random IR bursts that match a particular code is small.
From: Phil Allison on 11 Apr 2010 01:23
"Catwatcher" > Had a similar problem with a dish network box about 2-3 years ago. The > CFL was in a floor lamp line-of-sight about eight feet in front of the > box. Pressing a key on the remote would yield unexpected results. After > several days we correlated the problems with the light (which wasn't used > all the time). I suspect the CFL emitted significant IR which confused > the receiver in the box. ** Ordinary incandescent lamps emit lots of infra-red energy and have no such effect - cos the IR is not modulated like the light coming from the LED in a remote. So, what is different about CFLs ? Well, the internal inverter circuit operates at around 40kHz, so that must be the culprit. But I see no way a CFL can generate MODULATED infra-red light - certainly the tiny filaments will not do it and the phosphors have little IR output and enough persistence to eliminate light modulation at such a high frequency. However, the high voltage, high frequency drive to the fluoro tubes IS radiated for several metres and can be picked up by sensitive electronic devices. Just wave a scope probe near one and you will see what I mean. The photodiode amplifier circuit in an IR receiver is very sensitive, operating down to the microvolt level, so it must be possible for a CFL radiating the same operating frequency to interfere with them. ..... Phil |