https://devzone.nordicsemi.com/f/nordic-q-a/8487/what-could-make-radio-peripheral-not-work-in-nrf51822Hello! Sorry for my English) My situation is next: I have a custom PCB with nRF51822 on it. And radio control application works fine on this PCB. I don&#39;t know which of radio protocols this PCB uses because I don&#39;t have source codes for it. But my tasken-USTelligent Community 13Fri, 11 Dec 2015 20:29:40 GMThttps://devzone.nordicsemi.com/thread/30968?ContentTypeID=1Fri, 11 Dec 2015 20:29:40 GMT137ad170-7792-4731-bb38-c0d22fbe4515:88d99705-bcc2-4c00-a37d-a287cdc772e9Daniel<p>Why in the photo of your board the caps C5 and C6 are missing? I suppose they are the caps for the 16Mhz crystal. Without them, the cristal won&#39;t start at all. Try this:</p> <pre><code>Cload = 2*CL - Cpcb - Cpin </code></pre> <p>Where Cpcb = 4 and Cpin = 2.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/30966?ContentTypeID=1Sat, 08 Aug 2015 10:23:10 GMT137ad170-7792-4731-bb38-c0d22fbe4515:6f261e80-06d2-495d-8160-20f6da89defeQuangca<p>You show me all PCB parameter material. Maybe i can help you to design PCB antenna</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/30967?ContentTypeID=1Mon, 03 Aug 2015 11:42:22 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c1517ac1-2a4b-4583-97b1-ceaca1c12e65Susheel Nuguru<p>When you said that another board work fine with your code, do you mean that your notebook and tablet were able to find it?</p> <p>Then , on your custom board, are the pin mappings to UART same as the other? Are you using same clocks on the board that is working?</p> <p>The antenna on this board is ok, should be make the packets disappear atleast.</p><div style="clear:both;"></div>