Pulsed electromagnetic field indicator

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Discussion Overview

The discussion revolves around designing an indicator that lights up in response to a pulsed electromagnetic field, specifically for a medical application related to bone growth stimulation. Participants explore various methods to confirm the presence of the electromagnetic field using an LED housed in a small flashlight.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant seeks advice on creating an LED indicator that activates near a pulsed electromagnetic field, asking for necessary internal components.
  • Another participant inquires about the source, strength, frequency, and pulsing rate of the electromagnetic field, suggesting the use of an AM or FM radio to detect the pulses.
  • The original poster clarifies that the field strength is 790 milligauss, with a pulse frequency of 3.8 kHz and 350 pulses per second, and expresses interest in visually confirming the device's functionality.
  • A suggestion is made to use a pickup coil to generate a voltage that could be amplified, with a reference to EMF meters popular in ghost detection.
  • The original poster considers purchasing a gauss meter and questions whether a lower-cost model would suffice given the specific frequency of their device.
  • A participant expresses uncertainty about the effectiveness of the Elf Zone reader, noting its sensitivity and wideband capabilities.
  • The original poster reports that attempts to detect the electromagnetic field using both AM and FM radios yielded no interference, leading to a decision to try the gauss meter instead.

Areas of Agreement / Disagreement

Participants have not reached a consensus on the best method to detect the pulsed electromagnetic field, with various suggestions and uncertainties remaining about the effectiveness of different devices and approaches.

Contextual Notes

There are unresolved questions regarding the specific requirements for the LED indicator's design and the effectiveness of the suggested detection methods, including the limitations of the gauss meter and the radio experiment.

Trikemenace86
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I just found this forum and would love some help on creating an indicator that lights up when placed next to a pulsed electromagnetic field. I'm thinking a small LED that lights up when placed near a pulsed electromagnetic field to confirm the electromagnetic field is active.

How would I design this? I would like to use the housing of a small key ring flashlight with an LED in it.
My question is what internals would I need to create the LED to turn on simply by placing the unit near a pulsed electromagnetic field?

Thanks for the help guys
 
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Trikemenace86 said:
I just found this forum and would love some help on creating an indicator that lights up when placed next to a pulsed electromagnetic field. I'm thinking a small LED that lights up when placed near a pulsed electromagnetic field to confirm the electromagnetic field is active.

How would I design this? I would like to use the housing of a small key ring flashlight with an LED in it.
My question is what internals would I need to create the LED to turn on simply by placing the unit near a pulsed electromagnetic field?

Thanks for the help guys

Welcome to the PF.

What is the source of the field? How strong is it, and what is the center frequency? How often is it pulsed? If you hold an AM radio next to it, can you tune the radio to hear the pulses? Or maybe an FM radio?
 
It is a medical application for use as a bone growth stimulator to promote healing of bone fractures.
My interest is in proving that the unit is actually functioning and emitting a pulse. If I can show this visually by lighting an LED then I'm happy.

To answer your questions:
The pulsed electromagnetic field strength is 790 milligauss
The pulses are 3.8 kHz per pulse and 350 pulses per second

I havn't tried the radio experiment but that's a good idea and something I will try.

Let me know what you think
 
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Thanks for the help guys. I'm now considering buying a gauss meter. I noticed that most of them have a peak sensitivity in hertz- my device is putting out 3.8khz per pulse. Does this mean I'm going to need to purchase one of the more expensive units that reads kHz or will the $13 Elf Zone reader with LED's suffice?
 
Elf Zone reader: I have no idea what this will do. It could pick up stray fields in your environment or any local ghosts you may have (? :nb)). Or it may work fine.
It seems sensitive and wideband (to 10KHz)
 
I tried the radio experiment both AM and FM and there was no interference with either frequency. I suppose that's understandable since the frequency is 3.8khz
I guess I will buy the cheapest gauss meter (elf zone) and see if that picks up anything from the device
 

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