Why does my TV turn on by itself sometimes?

  • Thread starter DaveC426913
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In summary, the TV in the speaker's bedroom occasionally turns on spontaneously, even without any lightning storms. This was discovered to be caused by a passing streetcar which emitted a strong electromagnetic pulse (EMP) that triggered the remote sensor on the TV. The speaker also mentions their cordless phone being affected and questions how an infrared (IR) signal could pass through walls. However, it is determined that it is not the IR signal causing the TV to turn on, but rather a spike in the IR detector circuit due to a possible loose wire or mains spike in the household wiring. This is similar to a small EMP from a nuclear bomb.
  • #1
DaveC426913
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I just found out why the TV in my bedroom will very occasionally spontaneously try to turn itself on. I've experienced this before, during a lightning storm. A good close hit will sometimes cause the TV to try to come to life (it's twenty years old and makes a loud piercing twang upon turning on). There's no mystery that it's coming to life because remote sensor is being triggered by the same frequency as the remote. (The TV doesn't actually turn on, it just goes through the motions of doing so. It will also do this if you don't properly press the button, or double-press it.)

Last night, though there was no lightning storm, it tried to come on spontaneously anyway. It's done this before. This time I was able to identify the cause: a passing streetcar. My bedroom window is about 50 yards down a sidestreet from the main streetcar line in our Toronto satellite town. The spark from the cable must have sent out a sort of EMP, including the freq used by my TV remote.


Funny thing though, while the TV is now 20 years old, I presume it still operates on an IR signal. How could an IR signal pass through my walls? Or could it be strong enough to bounce in my window through a 90 degree angle?


Oh yeah, the cordless phone also tried to come to life.
 
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  • #2
That reminds me of the movie: "The Ring".
 
  • #3
IR imaging devices can see through walls, but a TV sensor can't (unless it's one bloody powerful burst). Anyhow, that's not something that one would expect from a tram. Also, I assume that the Transit Authority has RF emission rules that prevent radio interference, the same as any other consumer situation. That aside, though, a remote control uses a coded pulse sequence, not just a flash of light.
A 20-year-old TV pretty certainly uses IR for the remote; the old ones were ultrasonic, with a different pitch of tuning fork for each function. When you push a button, a little hammer hits the appropriate fork and an accoustic sensor in the TV detects it. I've never heard of a radio-control for that.
I think that you're just haunted.
 
  • #4
It's not the IR that is turning it on - it is spike in the IR detector circuit.
For some reason I never understood TVs tend not to be separately grounded (once got a nasty shock off a metal screen inside one) so they are sensitive to any ground spikes.
 
  • #5
mgb_phys said:
It's not the IR that is turning it on - it is spike in the IR detector circuit.
That makes more sense.

So, it really is an EMP then? Much like from a nuclear bomb, writ small.
 
  • #6
Possibly if there is a loose wire or unterminated track acting as an antenna, but more likely to be a mains spike.
 
  • #7
mgb_phys said:
Possibly if there is a loose wire or unterminated track acting as an antenna, but more likely to be a mains spike.
Oh, you mean through my household wiring?
 

1. Why does my TV turn on by itself?

There could be several reasons for your TV turning on spontaneously, including a faulty remote control, a power surge, or a software glitch. It is best to troubleshoot the issue by checking your remote control batteries, power outlet, and TV settings.

2. How can I stop my TV from turning on randomly?

If your TV is turning on by itself, you can try unplugging it from the power outlet for a few minutes and then plugging it back in. This can help reset the system and resolve any software issues. You can also check your TV's settings and disable any automatic power-on features.

3. Can a power outage cause my TV to turn on spontaneously?

In some cases, a power outage or power surge can cause your TV to turn on by itself. This could be due to a power surge damaging the TV's internal components or a temporary spike in electricity causing the TV to turn on. It is recommended to use a surge protector to protect your TV from power surges.

4. Why does my TV turn on at the same time every day?

If your TV is turning on at the same time every day, it could be due to a scheduled programming feature. Some TVs have a setting that allows you to set a specific time for the TV to turn on automatically. Check your TV's settings to see if this feature is enabled and adjust it accordingly.

5. Is my TV possessed if it turns on by itself?

No, your TV is not possessed. In most cases, there is a logical explanation for why your TV is turning on by itself. However, if you have ruled out all possible causes and your TV continues to turn on spontaneously, it is best to consult a professional technician to check for any hardware issues.

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