ganymede
Enlightened
As titled, does strong EMF and/or RFI has any effects on LED flashlight's onboard circuit board whether they are current limiting or PWM type?
Thanks.
Thanks.
Way too many threads been made on this topic and they all get closed.
As titled, does strong EMF and/or RFI has any effects on LED flashlight's onboard circuit board whether they are current limiting or PWM type?
Thanks.
1) Find a portable AM radio.
2) Tune it to an empty spot at the low end of the band.
3) Turn on the flashlight and hold it up to the radio's antenna.
If you hear the flashlight's PWM circuit buzzing in your radio, EMF is getting out. And if EMF can get out, it can also get in.
More food for thought -
One point of ingress and egress for EMI/RFI is directly through the lens, which by definition is not made of metal. While a thin coating of a conductive material can be vapor-deposited onto the lens, this will only provide very weak protection against electromagnetic fields. Anything that has a lens is vulnerable because of the lens.
As an example, many years ago I was running a video camera at a live event on an outdoor stage. It just so happened that the event was being held a half mile away from a radio station's transmitter tower. While the camera's body was very well shielded and did a great job of deflecting RFI, any time I pointed the lens in the direction of the tower I got a screenful of hash. There was no way to shield the optics from the RFI.
Guys,
Thank you all for the great inputs, the main reason I am asking this question is because some flashlight manufacturers advertise their lights as designed to "Mil-Spec", so I am assuming a piece of equipment designed and tested to military specifications generally speaking are shielded against some EMP and RFI no?
LED flashlights are great, great runtime and super bright but if a burst of EMP or RFI can potentially fried out the circuit board are they (LED) still the preferred choice? Quoting Murphy's law here, things that can fail will fail. Keeping things simple, any assault rifles can fail but not a bayonet.
LOL , mil-spec , i can just imagine a "opposition" parked away from a base with a Df directional antenna with a receiver that tunes from 30khz to 400khz or so listening out for those on low power or moonlight mode using PWM .
Positioning! :naughty:
So than an emf resistant light may also be ghost resistant? :naughty: