Well a radar detector is kind of like an eye. If you have your eyes looking through the windshield, it is easy to see what is ahead of you. If you have your eyes between the seats in the console, it is much harder and you will crash
Radar itself is slightly different as the waves have a tendency to bounce (which is how radar works in the first place). As you drive there will be some radar that will go into the car and ricochet all around the interior and probably go into the detector sitting in the console.
That said, this will happen MUCH later than it would happen if you had it looking through the window.
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