This question was posted on e2e.ti.com:

I have a CC2500EMK (old design:Chipcon 1.0) the firmware runs perfectly well when this emk is attached with the module(performace is good) but when attach my own emk using the new CC2500EMK 062 reference design from the ti user guide  the performace is really is causing concern with high PER.

I have tried to maintain all precautions mention in the guide.

Can anyone please suggest what might be causing this performance issue with my design.

What is the performance difference between the 2 designs available on the ti website.which one should be referred for production use.

Pinter Electronics Consultants’ answered:

Chris Pinter answers, “The EM board provided by TI is designed to give you the best possible performance.  The board you designed might not work as well.   Depending on your schematic, PCB layout and even other wires and parts not related to the radio can affect the performance.   Based on the information you provided I strongly recommend you take a look at the layout of your board and make sure signals are not interfering with the SPI lines and the RF lines.”

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