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I'd like some help in my attempt to phisically disable a wireless module and prevent it from emitting RF, or at least reduce them.

The module in question is part of a gaming console (Playstation 4) and works as a Wi-fi and BT transmitter/receiver. Neither of them I actually need because I'm using a Lan cable for internet and a wired controller instead of the original wireless BT one. On the other hand I'd like to reduce RF output from console to minimum because I'm affected by recurrent dermatitis due to proximity RF (iPad and wi-fi computers primarily) and would like not to give up using devices.

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The chipset is a Marvell Avastar, soldered on the PCB, with three antenna traces leaving it, two of which lead to integrated Wi-fi antennas (in red), while the third and shorter trace (in blue) leads to a U.FL connector. This U.FL is connected to a cabled BT antenna.

I removed the BT antenna and actually I could notice the original wireless controller now works only within a shorter range (1-2 meters instead of previous 7-10). I don't even know if it means the RF output decreased at all or, as I read somewhere else, I ended up concentrating the output in a closer range, thus making it more harmful.

What could I do next to get a better and definitive result? Unsoldering the module should be my last resort because I can't know if the console will keep working after that. I read about:

  1. Cutting the BT antenna trace as close to the module as possible
  2. Connecting the antenna trace to ground (to dissipate the current originated by the module?)
  3. Any other options?

Would be really grateful if any expert could help me out, taking in mind I'm no engineer unfortunately. Thanks a lot!

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  • \$\begingroup\$ "as I read somewhere else, I ended up concentrating the output in a closer range" Urf. Be careful with what you read. Physics isn't so flexible as to be "concentrated". \$\endgroup\$ – Ignacio Vazquez-Abrams Oct 2 '16 at 12:27
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    \$\begingroup\$ Fiddling around with the antenna will only distort the signal and weaken the range. You'd need a dummy load connected instead of the antennas to "eat up" the radiation. Alternatively, I'd try to cut the power supply to the chipset. \$\endgroup\$ – Felix S Oct 2 '16 at 12:29
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    \$\begingroup\$ Build a Faraday cage and put the PS4 inside it. \$\endgroup\$ – Captainj2001 Oct 2 '16 at 14:32
  • \$\begingroup\$ @Captainj2001 would you address me any internet source for a proper way of building an effective Faraday cage by myself please? \$\endgroup\$ – Giuseppe Spera Oct 5 '16 at 8:44
  • \$\begingroup\$ Wrap conductive sheet/foil/mesh all round. Keep any gaps less than about 5mm. thats a faraday cage good to a few GHz. Simple, cheap and effective. \$\endgroup\$ – Sean Houlihane Oct 5 '16 at 22:51
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Your dermatitis is not caused by the WiFi. The radiated power emitted by these devices is far too low to cause physiological effects. The most discomfort these electronics would cause would likely be due to thermal effects.

Instead, look for other sources of your rash. Certain metals may cause an allergic reaction in some people; nickel and chromium are common sources of problems. There are some plastics that also cause rashes in some people (Fitbit learned this with their first release of their Flex tracker; more recently McDonald's recalled a bunch of plastic toys for the same reason.) Reactions to plastics are sometimes due to outgassing, so it might not even have to make direct skin contact to cause the rash.

It's also possible your device's finish is harboring bacteria or fungus, which remain alive in tiny pores in the surface, living off of your sweat and dead skin cells. These could re-infect you every time you play.

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  • \$\begingroup\$ This answer does not help anyone with the same problem. Just because OP mentioned recurrent dermatitis does not mean not answering the actual question is the solution \$\endgroup\$ – divB Jan 14 '18 at 9:59
  • \$\begingroup\$ Destroying hardware for invalid reasons is pointless. I'll agree that I did not answer the question about disabling the RF, but only because in that context his solution is invalid. \$\endgroup\$ – John Deters Jan 15 '18 at 2:58
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I'm rather dubious about how much this will help, but the least intrusive thing to do would be buy some 51 ohm 0603 (I think thsat is the size on your board) surface mount resistors, and connect 3 of them from the stripline to the groundplane. This will absorb the transmitted power quite effectively (not 100% for the two wifi antennas, you need to cut the track on the antenna side). There are already pads in a suitable position for each of the 3 locations you marked.

These are tricky to solder, but not really dificult. If you terminate the striplines cleanly like this, the short lengths of track won't radiate (and the radio won't know its been disabled).

Disabling the module might cause a fault to be detected by software.

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