Spivver, I have a tradesman's knowledge of radar (at least where...

Spivver, I have a tradesman's knowledge of radar (at least where it was 30yrs ago) but nothing specific on radar detectors, hence I have kept my comments very general.
Your explanation of the local oscillator freq being radiated is what I was trying to explain in my first post. The problem is that you can't make a conventional (cheap) superhet reciever to work at these super high frequencies. As an example of the problem, the wavelength of 33ghz is approx 1cm, so a tuned half wave dipole is 1/2cm long. Any piece of wire 1/2cm long with this freq applied is a resonant circuit, or tuned antenna, NOT a piece of wire. Impossible!
The mixing of the local oscillator and recieved frequency MUST therefore happen at the antenna. Ergo, the LO freq is being applied to the antenna. With an aerospace budget the problem can be overcome.
Gotta go to work.....Momma