Since the noise source generates a very wide bandwidth signal, this causes the mirror suppression algorithm of the tinySA ULTRA mode to fail. When the scanning frequency is greater than 3GHz the IF frequency of tinySA ULTRA switches from IF=LO-RF to IF=RF-LO, but due to the failure of the mirror suppression algorithm the RF-2IF signal is still displayed and you can see that the signal strength at 3.2GHz is close to that of the signal strength at 1.3GHz.
This is why we require the user to enter the unlock CODE in order to turn on ULTRA Mode, and we hope that the user will fully read the restrictions on the ULTRA Mode page before turning on ULTRA Mode.
The ULTRA mode of the ZS407 uses the same technology and is subject to the same limitations, except that this step occurs at a higher frequency.
