Can a 3V/m Electric Field Detector Detect Someone on the Other Side of a Wall?

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Discussion Overview

The discussion revolves around the capabilities of a 3V/m electric field detector, specifically its ability to detect human presence through walls and the nature of electric fields emitted by the human body. Participants explore the sensitivity of the detector, the conditions under which it operates, and its application in various contexts, including detecting geomagnetic storms and potential paranormal phenomena.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • One participant questions how the human body can emit an electric field and whether a 3V/m detector is sensitive enough to detect it through a wall.
  • Another participant suggests using a 9V battery for experimentation.
  • Some participants express skepticism about the existence of an external electric field generated by the human body, noting that any significant electric field typically dissipates quickly unless in dry conditions.
  • Details are provided about the Trifield Natural EM meter, including its sensitivity to electric fields and its ability to detect human presence, though it is noted that it may not always be reliable.
  • Concerns are raised about the manual's language regarding the emission of electric fields by humans, with suggestions that it may be misleading.
  • Participants discuss the variability of electric fields in real-life situations and the limitations of measuring at a single point in space.
  • Some mention that electric fields from electrified individuals can reach hundreds of V/m depending on proximity.
  • Questions arise about the meter's ability to measure the Earth's magnetic field and the necessity of rotating the device to obtain readings.
  • A participant shares a theory involving dark matter and its potential electric charge, linking it to experiences of seeing figures in haunted locations.
  • Technical explanations are provided regarding the operation of meters in relation to induced electromotive force (emf) and the challenges of measuring static magnetic fields.
  • Inquiries are made about where to purchase Hall Effect devices and particle beam tubes for further experimentation.

Areas of Agreement / Disagreement

Participants express a mix of skepticism and curiosity regarding the electric field detection capabilities of the meter, with no consensus on the nature of electric fields emitted by the human body or the effectiveness of the detector in various conditions. The discussion remains unresolved on several technical points and theoretical implications.

Contextual Notes

Participants highlight the inhomogeneous nature of electric fields in real-life situations, the potential for misleading language in the meter's manual, and the challenges associated with measuring static magnetic fields. There are also references to the limitations of the detector's sensitivity and the conditions under which it operates.

jlcd
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I bought this electric field detector that can detects minimum of 3V/m. It said the human body can emit electric field.. so the detector can detect the presence of someone on the other side of a wall. May I know how the human body can emit electric field.. and is a detector with a 3 V/m really sensitive? what other devices can detect such low reading too?
 
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Experiment ! Use a 9V battery or something.
 
External human generated electric field? I don't think so. In so far as the human body can accumulate an external static charge you could have a significant electric field but it usually dissipates except in dry conditions. The internally generated voltages are only of the order of 10's of millivolts
 
gleem said:
External human generated electric field? I don't think so. In so far as the human body can accumulate an external static charge you could have a significant electric field but it usually dissipates except in dry conditions. The internally generated voltages are only of the order of 10's of millivolts

I bought this Trifield Natural EM meter. https://www.amazon.com/dp/B00H4CXUWC/?tag=pfamazon01-20

I brought it to a mall. When set to Electric Field. The needle can indicate reading when people walk 1 to 2 meters in front of it. The manual inside says:

"When the dial is set to ELECTRIC, the meter is sensitive to electric fields as weak as 3 V/m (volts per meter). To illustrate just how feeble a field this is, a 10'x10'x10' room filled with a field of this strength has a total amount of energy equivalent to that required to lift a single grain of table salt 1/50th of an inch. Indoors, electric fields typically fluctuate 1 or 2V/m. By settting the minimum sensitivity to change at 3 V/m, we have designed the meter to disregard this "background noise". Human beings and animals usually emit an electric field which is easily detectable using the Natural EM Meter. In fact, the meter can be used as a motion-activated intruder alarm, depending on the type of wall and the charge on the person. It is so sensitive that it can detect the presence of an person through a wall. Though it is not foolproof in this capacity, (sometimes a person will carry no electric charge and thus be "invisible" to the meter), it's sensitivity is of interest to researchers."

My question, does it mean my meter is detecting the total 3 V/m in a room or from a particular source? I use the meter to detect geomagnetic storm, etc.
 
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Does you ghostmeter show approximately half a Gauss (50 ##\mu T##) for the Earth magnetic field ?
 
jlcd said:
My question, does it mean my meter is detecting the total 3 V/m in a room or from a particular source? I use the meter to detect geomagnetic storm, etc.

It is detecting the electric at that point in the room. the electric field in a real life situation is very inhomogeneous so measuring at one point does't tell you anything about the field elsewhere. The use of the term 'filled with a field of this strength" is meaningless the total the electric field content of a room is immaterial to the value at a given point and the force that it can exert on any electrified object.

In the manual states that the instrument has a built in threshold set to disregard electrical field noise of up to 2 M/m and will give no reading less than 3 V/m I believe that the manual is using misleading language in stating that people "emit" an electric field. They correct this misstatement later by more correctly attributing the electric field to the electric charge that they might be carrying.

Electric fields of an electrified person can be hundred of V/m depending on how close you are to them.

Its ability to detect electrical storm is due to the electromagnetic field pulse sent out by the lightning discharge. AM radios receive this as loud static.
 
gleem said:
Electric fields of an electrified person can be hundred of V/m depending on how close you are to them.
Absolutely true. It could be exactly the same for a damp mattress or a log, placed in the same place as the human.
The biggest electromagnetic effect that a human is likely to produce will be the dreaded Mains Hum, which you can get when touching the input to an audio amplifier. In a world with no mains electricity, your meter may not be quite as lively.
 
BvU said:
Does you ghostmeter show approximately half a Gauss (50 ##\mu T##) for the Earth magnetic field ?

This is also the part I want to know. The manual states "On MAGNETIC, the meter reads any change in the magnetic field caused by rotating the meter in the Earth's magnetic field, by a moving magnetic object, or by DC currents carried by wires or the atmosphere. The Earth's field strength is about 50 microteslas (500 milligauss), so rotating the meter from north to south rapidly (within a 0.5 second interval) causes a momentary reading of about 100 (a change from -50 to +50). If subsequently held still, the needle will settle back to zero. For the best readings of transient fields, the meter should be placed on a stationary platform because of sensitity to slight rotations while hand-held."

So why does the meter not show the approximately half a Gauss (50 ##\mu T##) for the Earth's magnetic field? Why do you have to rotate it to measure the Earth's magnetic field??

About it's being a ghostmeter. Well. I'm testing the theory that some dark matter configuration can emit slight electric charge. I have a friend who has developed the brain sensitivity such that when he closes his eyes. He can still see images.. in haunted house.. he can see figures moving around.. some researchers who use the meter on the figures has detected reading. I am thinking if its related to some kind of synesthesia.. where instead of people see colors.. they can map the electricified dark matter object in their brain and track it around. On living people. my friend can also track this thing around the body. So after death, the thing has simply separated and there is lesser cohesion and they are simply what you may call "ghosts". Of course I bought the meter to test the theory and debunk it. But first I need to learn how to detect normal objects electric field and Earth magnetic fields.
 
jlcd said:
So why does the meter not show the approximately half a Gauss (50 μTμT\mu T) for the Earth's magnetic field? Why do you have to rotate it to measure the Earth's magnetic field??
Good question. We'll have to ask the maker, for I have no idea.

About it's being a ghostmeter.
Just joking :rolleyes: .
 
  • #10
jlcd said:
So why does the meter not show the approximately half a Gauss (50 μTμT\mu T) for the Earth's magnetic field? Why do you have to rotate it to measure the Earth's magnetic field??
A simple meter will work on induced emf whilst the magnetic field changes. One way to change the field is to change the direction of the coil. Measuring a static field without moving a test coil is much harder and would require a Hall Effect device or an electron beam tube where charges are deflected..
 
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  • #11
sophiecentaur said:
A simple meter will work on induced emf whilst the magnetic field changes. One way to change the field is to change the direction of the coil. Measuring a static field without moving a test coil is much harder and would require a Hall Effect device or an electron beam tube where charges are deflected..

Do you know where to buy these Hall Effect device or particle beam tube?
 
  • #12
jlcd said:
Do you know where to buy these Hall Effect device or particle beam tube?

You can buy all sorts of Hall Effect units (try Google) but you would need to know the specification that you require.
There are many electron tubes available (like CRT TV tubes and school demonstration equipment) but they would need to be part of a whole set of gear. Or you can buy a Magnetometer, which will cost you an arm and a leg, probably. Again, you would need to specify the performance you require. They are used all over the place to measure variations in the Earth's magnetic field, surveying archeological sites for instance. This isn't a subject I have ever been involved in and you would need to get expensive specialist advice, to choose exactly what it is that you need. (If you have any idea, that is)
You say you have bought a device already but you don't exactly say what the application is. Some of your ideas are definitely not PF business. Your statement about "Dark Matter" is clearly nonsense as no one has actually laid their hands on a bucket of the stuff.
Have fun.
 
  • #13
BvU said:
Experiment ! Use a 9V battery or something.

I tried a 9V battery.. it can't seem to detect it.. it's just detecting my fingers when I hold the battery close to the detector.. why.. what is the magnitude of electric field created by a 9 volts battery? I tried a comb in my hair and there is a reading as it has detected the electric charge in my comb.
 
  • #14
jlcd said:
I tried a 9V battery.. it can't seem to detect it.. it's just detecting my fingers when I hold the battery close to the detector.. why.. what is the magnitude of electric field created by a 9 volts battery?

there won't be any externally detectable electric field until the battery is powering a circuit
 
  • #15
Thread closed for Moderaton...
 
  • #16
jlcd said:
About it's being a ghostmeter. Well. I'm testing the theory that some dark matter configuration can emit slight electric charge. I have a friend who has developed the brain sensitivity such that when he closes his eyes. He can still see images.. in haunted house.. he can see figures moving around.. some researchers who use the meter on the figures has detected reading. I am thinking if its related to some kind of synesthesia.. where instead of people see colors.. they can map the electricified dark matter object in their brain and track it around. On living people. my friend can also track this thing around the body. So after death, the thing has simply separated and there is lesser cohesion and they are simply what you may call "ghosts". Of course I bought the meter to test the theory and debunk it. But first I need to learn how to detect normal objects electric field and Earth magnetic fields.
We don't discuss nonsense here. Thread will remain closed.
 
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