Cell Phone/Network and Equinox Compatibility

Very interesting post, Joe - thanks for that input. All of that is starting to get above my pay grade! I know nothing about the tolerances that cell phones or any other electronic equipment need to conform to in order pass muster with FCC regulations, and I know even less about what happens with frequencies and harmonics when radio signals get transmitted.

I would guess that in the case of phones there must be some sort of low level harmonic that might be interfering? Would the FCC disregard those kinds of transmissions if it doesn’t transmit beyond a certain range? Do they even regulate very low frequencies at all? For example, I’ve heard plenty of people mention that most, if not all, metal detectors transmit harmonic frequencies along with the main frequencies - those frequencies just don’t get used for processing the data. If that’s true, the FCC hasn’t seemed concerned with it

AirmetTango said:

Very interesting post, Joe - thanks for that input. All of that is starting to get above my pay grade! I know nothing about the tolerances that cell phones or any other electronic equipment need to conform to in order pass muster with FCC regulations, and I know even less about what happens with frequencies and harmonics when radio signals get transmitted.

I would guess that in the case of phones there must be some sort of low level harmonic that might be interfering? Would the FCC disregard those kinds of transmissions if it doesn’t transmit beyond a certain range? Do they even regulate very low frequencies at all? For example, I’ve heard plenty of people mention that most, if not all, metal detectors transmit harmonic frequencies along with the main frequencies - those frequencies just don’t get used for processing the data. If that’s true, the FCC hasn’t seemed concerned with it

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Nearly every electronic device emits unintended emissions of some kind, and most are of no consequence. I have no doubt the Equinox emits out of band signals as well, but that's not the issue here. The issue is a cell phone several feet away from a receiver such as a metal detector is pretty consequential. As you describe "harmonics" would be acceptable if devices were within a few inches of each other, but not feet away.

The Equinox works in the VLF (although the 40 kHz frequency is technically LF) range and at very low levels of emitted radiation. There's not much down that low that will be an issue and I'm pretty sure the metal detector manufacturers certified Part B on a declaration basis... they don't have to be submitted for certification.

Cell phones operate in congested frequencies and are pretty tightly regulated. There are multiple certifications required and devices and specifications must be submitted for certifications. I don't know all the various rules, but I really doubt out of band VLF emitted radiation would be acceptable. There are a lot of medical and other critical devices that use VLF and you certainly wouldn't want a cell phone interfering from feet away from such a device.

For example, the walk-thru detectors at airports generally work way down below 3.5 kHz. They're designed to not interfere with pacemakers, etc. as long as it's very brief exposure (you wouldn't want to stand in one and read a newspaper with an implanted electronic medical device). Some of the hand held detectors use the same 20 kHz frequency as our detectors, but most are higher up in the LF band... but TSA agents are supposed to be trained to keep those devices away from pacemakers, etc. as they can cause interference.

Oh well, I could go on and on, but the bottom line is that a cell phone has no business emitting VLF out of band emissions that disrupt devices several feet away.

-Joe

I got a Samsung Android on MetroPC, (T-Moble), and no issues.

Samsung S9 Verizon 4G network no problems. I do get EMI issues but not from the phone. EMI is bad in only in certain parts of town.

The weird part is the wireless headphones are designed to take calls to your cell phone. At that point in time it says it will interrupt the detector.