enter image description hereThis has been driving me crazy for several years now -- my soft touch lamp has been turning itself on most mornings. Some details:

It is definitely tied to sunrise/dawn, as the time each day varies along with the sunrise. This makes me think it could be related to some voltage/current fluctuations that could occur at that time each day -- perhaps street lights turning off? But it does not happen EVERY day.

Also, a second lamp will USUALLY turn on at the same instant, but not always. Note we live in Mexico and line voltage fluctuates more than is normal in the U.S. If I turn it off immediately it will turn itself on again either immediately or within 10 - 15 seconds. This window during which this occurs is 2 - 3 minutes long.

I hope someone can explain this, because my fallback answer is that it's haunted...

[Edit]I'm attaching a photo that shows the lamp just after it went on at 7:20 one morning. The alarm clock is NOT connected to the lamp. The lamp is just a simple almost spherical shape. Unfortunately it does not have any model number or manufacturer information.

  • \$\begingroup\$ Are you sure it doesnt have an alarm clock? What is this lamp anyway? \$\endgroup\$ – Eugene Sh. May 1 '19 at 18:48
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    \$\begingroup\$ Your question would be interesting if you gave a make and model for the lamp, a photo of it and the PCB, details of the type of bulb you are using and your best effort at a schematic. There is an edit link under your question ... \$\endgroup\$ – Transistor May 1 '19 at 19:00
  • \$\begingroup\$ Here is the edit link. \$\endgroup\$ – Eugene Sh. May 1 '19 at 19:02
  • \$\begingroup\$ How do you switch the lamp ON/OFF usually? How does it behave if unplugged/plugged into the wall? \$\endgroup\$ – Eugene Sh. May 1 '19 at 19:23
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    \$\begingroup\$ It's a crappy design. Give it away. It appears to be RF noise sensitive which may be coincident with changing AC Line levels in the morning, your mobile phone or even plug orientation sensitive or even proximity of a noisy RF clock. It's like guessing what caused stack overflow on some random embedded product or where's Waldo. My guess is it is supposed to sense an increase in stray line noise when you touch or get near the globe. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 1 '19 at 20:02

Since I can not comment I will post my comment as an answer.

I have a very similar sight (same?) and I have tried many things to 'fix' it. Finally one day I discovered that at the same time I pulled my back door closed (well, sort of slammed it) the light turned ON. Then the same action would also turn it Off.

I knew both the lamp and the back door light were on the same circuit. I discovered that a few of the wires in both the light switch, back door light and where the lamp where plugged in were loose. (my house is 70 years old). After tightening all of the wires my lamp has never malfunctioned again.

  • \$\begingroup\$ thanks for your thoughts -- it seems like in your case mechanical vibrations and loose wires could interact, but there are no mechanical vibrations going on in this scenario. \$\endgroup\$ – ckapilla May 1 '19 at 20:22

There's been some detailed analysis of similar problems - for example here

Summary - RF energy gets into the switch IC and causes random ON/OFF.

The solution is to wire inductors or resistors in series with the touch connection to the lamp metal housing to isolate the control from a hostile EMC environment. See the link for details, but the values are around the 1k - 5kohm mark.

Note that working on such a lamp and modifying it may be hazardous if you're not familiar with mains electrical work.

  • \$\begingroup\$ thanks for the interesting link. I'm not really looking to fix the problem (it's not a big bother since it just happens once a day), I just want to understand what could possibly be the source of this that is tied to the sunrise somehow. \$\endgroup\$ – ckapilla May 2 '19 at 21:18

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