From million miles. It actually can detect aircraft flying in Mars orbit.
The Russian radars are not capable to do that, but of course the US military doesn't know the meaning of impossible : )
they write about the capability of Hawakeye :
“It is the physics of longer wavelength and resonance that enables VHF and UHF radar to detect stealth aircraft,” Westra wrote in his article, titled “Radar vs. Stealth.”
UHF-band radars operate at frequencies between 300 MHz and one GHz, which results in wavelengths that are between 10 centimeters and one meter long. Typically, due to the physical characteristics of fighter-sized stealth aircraft, they must be optimized to defeat higher frequencies in the Ka, Ku, X, C and parts of the S-bands.
So, just to compare: the hawkeye has a 7.3*0.7 meter big radar, the NEBO-M 60*6 meter big.
The Nebo 70 times bigger than the hawkeye radar.
Feel the difference?
so either the US military lie , or the NEBO-M can detect the f-22/35 from extreme distances : )
Pick your choice.
You can trash now the US military, and bragging about the incapability of them : ) and how rubbish the US navy and the hawkeye.
But the principle of operation to detect stealth is simple, and using the same principle like this antenna: