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First time poster here on electronics, so please excuse any big mistakes.

I'm working on a project that uses the NRF24L01+ chip for radio communication between an arduino uno and a raspberry pi. It sends a simple ascii char array which is interpreted by the pi as a string. The radios are being supplied with 3.3v from the boards.

I'm having a serious range issue, though. Everyone I've spoken to has said that they have had little problem having them work up to 100 meters apart. My units, while they work in the same room, loose connectivity immediately after walking around a corner, even if I'm less then 15 feet away. It seems to be a line-of-sight issue, but it's odd to me that the drop off is so fast.

I'm currently using the "naked" chips, which look like this: naked
I've seen them with "rubber-ducky" antennas before, though: antenna
(source: wikispaces.com)

My question: Would adding an antenna on top of the flat antenna help with my propogation issues? If so, how would I go about attaching the antenna? Would standard leaded solder do the trick?

Thanks in advance for any answers.

Resources:

Data Sheet Schematic

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  • \$\begingroup\$ Have you considered getting an nrf24 that includes a PA/LNA and antenna connector? Adding an antenna by hand is not easy. I've done exactly what you're talking about. It worked, but not well. \$\endgroup\$
    – curtis
    Commented Jan 19, 2015 at 20:08
  • \$\begingroup\$ @curtis: I would totally consider it, but I'm just doing a proof of concept for a project. All I need is a few extra feet of range to get around that corner—if and when I actually deploy the project, I would invest in some new RF24's, but for now I'd like to use what I've got. Would you mind going a little in depth about how you attached the antenna? Thanks! \$\endgroup\$
    – afischer
    Commented Jan 21, 2015 at 12:19
  • \$\begingroup\$ I cut the trace where I thought the 50ohm interface was and the antenna started. On the naked nrf24, my guess would be right after the shorted stub, but that's just a guess. Then I soldered the center conductor of the whip antenna the the trace and the braided shielding to a ground pad. Performance will depend on selecting the correct spot to cut and how clean you can solder the new antenna without peeling the ground back very far. Mine was ugly and didn't work well. Good luck \$\endgroup\$
    – curtis
    Commented Jan 21, 2015 at 22:05
  • \$\begingroup\$ The ground pad is barey a ground. Just find out the wavelength and cut a (half-wavelength) dipole for it. Each leg is a quarter wavelength then. The dipole will provide a far better ground than some tiny pcb tracks. For best reception make sure the ends of the dipole are not pointing to where you want to communicate to. \$\endgroup\$
    – captcha
    Commented Mar 1, 2015 at 21:30

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I cut the trace near that resistance and soldered a +- 10cms,1.5mm copper wire. its working since 2 weeks ago perfect on Arduino with reed switch at 60m distance from the other Arduino.

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