https://devzone.nordicsemi.com/f/nordic-q-a/23550/is-it-possible-to-set-tx-between--20-and--30-dbmWe have a project which need to control the distance between the slave and the master to be less than 10m, say 5m. We tried -20 and found it a little longer than we expected and also tried whisper mode, -30, than it can work when the module stands aloneen-USTelligent Community 13Sun, 16 Jul 2017 12:12:37 GMThttps://devzone.nordicsemi.com/thread/92502?ContentTypeID=1Sun, 16 Jul 2017 12:12:37 GMT137ad170-7792-4731-bb38-c0d22fbe4515:84097ab3-61cd-4dc7-aebd-e3f1d8b1e7deendnode<p>No, all nRF5x chips support only values listed in <code>RADIO-&gt;TXPOWER</code> register of respective Product Specification. In general just values between -20 and +4dBm with 4dBm steps are usable. However what makes precise location impossible are neither TXPOWER values neither receiver&#39;s sensitivity (they typically work with 1dBm resolution in -90~+10dBm range so it doesn&#39;t matter if you transmit at 0dBm or -12dBm it should be the same usable effect in close range of 10-20m) but terrible dependency of 2.4GHz radio on surrounding topology. In other words even small variations like micro movements of transmitter and objects around can change it by +-10dBm (or even more) in next TX burst so you believe that device move quickly but it&#39;s staying on the spot, just shaking a bit.</p><div style="clear:both;"></div>