https://devzone.nordicsemi.com/f/nordic-q-a/455/nrf51422-don-t-run-on-the-second-timeHi, I have a wired problem with the nrf51422, I&#39;m loading the code using the J-link into my board or the evaluation board (PCA10007) that I have, the code runs perfect without any errors/warnings. but after I disconnect the debugger, power offen-USTelligent Community 13Thu, 19 Sep 2013 11:42:37 GMThttps://devzone.nordicsemi.com/thread/2372?ContentTypeID=1Thu, 19 Sep 2013 11:42:37 GMT137ad170-7792-4731-bb38-c0d22fbe4515:5a72daa3-d710-4c5f-bc84-a0e651d93091Hung Bui<p>Hi,</p> <p>ANT stack would not work if the LF clock tolerance is higher than +-50ppm (page 18 in nRF51422 Product Spec). You would need to use an external crystal with tolerance of &lt;+-50ppm for ANT protocol.</p> <p>Do you have the same issue with our PCA10007 ?</p><div style="clear:both;"></div>