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i am currently building a device that requires a NRF24L01 module to send radio waves to another NRF24L01 to be picked up and interpreted. This is a using an arduino running a code to transmit data via NRF and another arduino above it to receive those signals as seen below. enter image description here Everything works perfectly until the wireless charging coil which is in between the 2 NRF modules is turned on. After supplying power to the coil which powers the arduino above to receive NRF data from below no data is being perceived at all. Normally colors are supposed to change when the mouse moves, but instead the same color from what was left when other experimenting took place is the only color lingering as seen below. enter image description here After doing some experimenting and moving the arduino away from the coil and plugging it in all signals were being sent successfully. As long as the receiving end of the coil (or receiving end of the NRF module i'm not sure which one) wasn't too close to the transmitting end of the coil. Seen below are positions of the receiving NRF module where signals send from the transmitter were received successfully. enter image description here enter image description here enter image description here I understand this may not make a lot of sense so here is a short video describing what is happening. Video about problem

My question here is mainly what can i do to fix this issue? will changing the radio frequency from 2.4 GHz to 2.5 GHz or anywhere in between make a difference? Can i mount the NRF transmitter module on the green wall seen in the pictures so that it is above the wireless power coils? or do i need to use a different method of communication?

Here is the coil in question Coil. With the current arrangement when measuring with my multi-meter the receiving end is getting 0.004A or 4mA and the transmitting end is taking 0.01A or 10mA all at 12V. The rated current for the receiving end is 600mA and im not sure how much is being taken in from the transmitting coil when 600mA is reached up top.

here is the data sheet datasheet. Apparently the coils operate at 0-5MHz

UPDATE: The NRF module isn't receiving data because of the data being obstructed by the magnetic field, but rather because the magnetic field is messing with the receiving module itself. In order to solve the issue im going to have to move the NRF module higher up from the circuit board and data sends perfectly.

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    \$\begingroup\$ Can you add some more information about the wireless charging coils? What frequency do they use? Is there any form of core material (like in a toothbrush) or are they air cored? How much power is being transferred through them? \$\endgroup\$ – Jack B Apr 3 at 15:33
  • \$\begingroup\$ Okay, I updates to add more information about the coil at the bottom of the post. \$\endgroup\$ – Reese Houseknecht Apr 3 at 15:39
  • \$\begingroup\$ also is there an equation to calculate the frequency the coils operate at? if so can you tell me i would like to learn it and try it out \$\endgroup\$ – Reese Houseknecht Apr 3 at 15:45
  • \$\begingroup\$ Is the LED bar going to spin? Is that why the coils are located where they are? \$\endgroup\$ – Aaron Apr 3 at 15:52
  • \$\begingroup\$ You seem to have good range on your NRF modules, have you tried placing them so that their fields are orthogonal to the power coils field? \$\endgroup\$ – Aaron Apr 3 at 15:56
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As an additional option for your design, consider adding blocking elements to separate the wireless transmission of power from signal transmission. These could be Faraday cage style meshing dumped to ground or (possibly) some nickel based sheet metal stock. If it's easier to just move the receiver for data transmission, do that. If not, or if for some other reason you'd rather not move that receiver then maybe you can corral your signals using metal.

Here's a (wikipedia) example of EM shielding inside an old cell phone: https://en.wikipedia.org/wiki/Electromagnetic_shielding#/media/File:Electromagnetic_shielding_inside_mobile_phone.jpg

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After struggling with what was truly going on for a couple of days it became apparent on how I need to fix this. At first it was thought that the message being transmitted from the NRF module was being messed up and therefor not being received. It is now known the coil was only messing with the receiving NRF module, but data could still be transferred through the magnetic field. This is because the frequencies both devices operate at are totally different. The solution here is to move the NRF module higher up relative to the wireless coils and everything works. Steel which is magnetic and could divert the magnetic field could have been placed around the coils, but because of the spinning that will soon happen the friction damage isn't really an option for me and was never tested.

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  • \$\begingroup\$ I think this is better suited as an update to the original question. \$\endgroup\$ – chamod Apr 5 at 1:04
  • \$\begingroup\$ Well since keeping the module around the coil and just changing frequencies didnt work this is my only option and therefore best solution if this happens to anyone else \$\endgroup\$ – Reese Houseknecht Apr 5 at 5:57

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