https://devzone.nordicsemi.com/f/nordic-q-a/62458/nrf52-ble-radio-doesn-t-visible-on-custom-board-any-ideasHi, We made a custom board with nRF52 and it&#39;s BLE radio doesn&#39;t advertising, not visible on nRF connect APP. I tested a lot of example, like uart_peripherial,heart rate and nothing happens (the code runs normally). I tested this example too withen-USTelligent Community 13Wed, 17 Jun 2020 06:21:20 GMThttps://devzone.nordicsemi.com/thread/255391?ContentTypeID=1Wed, 17 Jun 2020 06:21:20 GMT137ad170-7792-4731-bb38-c0d22fbe4515:f271030d-f105-4dce-961e-ddef959a4668Susheel Nuguru<p>If your application is working only in debug mode, then it seems that the debugger is forcing the available clock ON. In the absence of external oscillator (or some fault) the debugger still forces internal RC to start.</p> <p>There are many such cases here in devzone, for example <a href="https://devzone.nordicsemi.com/f/nordic-q-a/17829/application-does-not-start-without-debugger-connected">this </a>one. Please check if your external oscillator is starting properly when not in debug mode.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/254829?ContentTypeID=1Sat, 13 Jun 2020 11:05:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d356eafc-e74c-42ba-9f52-eb3b5ee51340kurta999<p>The debugging works without any problem with J-Link, I can debug the application and it doesn&#39;t stop anywhere, it&#39;s running on both boards.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/254640?ContentTypeID=1Fri, 12 Jun 2020 09:15:28 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c9c0db6b-a615-4bec-9180-e39d55d13644Susheel Nuguru<p>It does not look like your custom chip has powered up correctly. Do you have any mechanism to debug your application like logs or debug port etc?. If so, I recommend you to debug to see if the application is starting at all and if starting, where is it failing.</p><div style="clear:both;"></div>