https://devzone.nordicsemi.com/f/nordic-q-a/28650/nrf51822-frequency-errorI have some units that seem to have a frequency error. Please see image below from a spectrum analyser. It is the received signal from 2 units both transmitting a constant carrier on channel 10. The peak on the left is a little low - 0.8mHz Theen-USTelligent Community 13Tue, 19 Dec 2017 10:41:19 GMThttps://devzone.nordicsemi.com/thread/113577?ContentTypeID=1Tue, 19 Dec 2017 10:41:19 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b8febf88-ee8e-4b23-bfcf-6222a2a1c1fdElliott Makin<p>Thank you - forgot to initialise the crystal - quite obvious really. Works perfectly now.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/113576?ContentTypeID=1Mon, 18 Dec 2017 18:27:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b22e043a-999e-4c83-b5f8-7954ed9ad8a6AmbystomaLabs<p>I would guess that you are running the test to measure channel accuracy with some custom code and have failed to invoke HF_EXT and are instead trying to run the radio on HF_INT.</p><div style="clear:both;"></div>