If you lock the target at 80nm with not A/A selected, when you select the A/A the Radar rage change to 40nm and the elevation antenna stuck and you are not able to move it.
as you can see in the picture the TDC is at the exact point the AWACS told me the enemies are, the altitude the radar is scanning is between -38 + 32 and the only aircraft spotted is the AWACS.
I've watched the Growling sidewinder's and RedKite's videos regarding how the radar works and I believe that i'm familiarized in how to lock targets in the radar. But seems that the TDC cursor altitude numbers are not corresponding correct with the increasing or decreasing of the antenna elevation.