nrf24l01 module location on pcb.

[Fabio Fernandes]

I am using NRF24L01 modules sold on ebay. I have 3 boards where these modules are soldiers and notice a big difference in range. More distant of other components, better range. What is the safe distance to other components of the pcb? Thanks

[Asbjørn]

The antenna characteristics is dependent on the distance to other metallic object, but there's no clear guide to how far. You see yourself that when you have the module some distance away from the board, it performance better. It's difficult to make repetitive measurements like this as the angle between receiver and transmitter could affect the result quite a bit. On board 3 the antenna is placed right above the board and potentially other metal parts, this will most likely de-tune the antenna. So the recommendation is to keep the antenna in as free open area as possible.

If you move the three module between the three board, do the module perform equally? By that I mean, if you take the module from board 1 and place it in board 3, does it perform equally to the module 3 in board 3 do? I suspect all the module perform equally, it's just a matter on where they are placed on the board that makes a difference.

[Asbjørn]

I don't know what kind of modules you have or where you got them from, but we have seen other customers struggling with similar looking modules that was supposedly based on nRF24L01+, but in reality was fake/counterfeit versions of nRF24L01+. I don't know if that's the reality for the modules you have, but if you see different performance in the same setup with just changing the modules and you see some modules independently of placement performing worse than other, it could indicate that these are not the real deal.