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Electronics/Smartphone activates dimmer lights


The lights in my girlfriends room are the type that can be dimmed and have never had any problems. No all of a sudden they started blinking and going on and off every now and then and getting dimmed and brighter on again. This usually happened in the evening and if i ignored it the lights kept living their own life but if i got up to check it (was kind of scary) it stopped. Today i for some reason noticed that it happens when I'm on the Internet with my smartphone. it never happened before but with my new galaxy S4 all of a sudden this happens. Now i can do it at will because it always happens when i turn on the internet. The only thing this phone has that my previous did not is a 4g connection. What is happening with the lights and how can a internet connection from my wireless phone make a light that isnt automated all of a sudden make it function automatically? The lightswitch has a buzzing sound every time before this happens.

I can send you a film so u can better se what is happening if you want to

I also wonder if phones should once again be banned from airplanes... :O

It looks like you are having rfi (radio frequency interference)!  It is very common when there are high frequency devices around each other.  Either the phone or the internet connection to the wi-fi modulator/transceiver are getting a high frequency signal into the dimmer circuit.

You might experiment with going a greater distance from the dimmer control. Determine how far before the interference is gone.  Then you know it is the phone function that is the greatest influence.  Then, next, try reorienting the wi-fi router by turning it or moving its antenna about to see if that influences the interference pattern.

You can probably find some way to eliminate the interference by the distance factor and the router box.  

Another solution may be to replace the dimmer switch in the wall with that of another manufacture which may not be so sensitive to interfering frequencies.

Hope this helps.  


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Graduate electrical engineer with over 40 years in electronic design, manufacturing, project organization and patent review. Experience in fields of industrial and consumer electronics (audio, video, acoustics, etc.)

IEEE (Institute of Electrical and Electronics Engineers); Senior Life member AES (Audio Engineering Society), Fellow Life member

BSEE University of North Dakota

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