Dale, hello. I may be able to help out. I too had that problem at first on this mod.
I have two questions for you. First, did you load the raduino firmware that ended with "_S", which denotes the signal analyzer...?
With V1.2, there are updated Nextion files which have the new features that you must load to your Nextion.
Lastly, be sure that you load the signal analyzer file v.07 file to your second nano you placed in the ubitx. There is a v.08, BUT that does not relate to THIS mod. Be sure to get the v.07. Hope that helps!