[InterceptPoint]

I helped MAKE Radars that can detect stealth jets! How do you think we knew they were stealth jets?

I think you are correct about that. Stealth aircraft are designed to minimize signal reflection in the direction of a received radar signal. They accomplish this by deflecting and/or absorbing these radar signals. But accomplishing that performance over all possible radar operating frequencies is, if not impossible, extremely difficult. I vote for the impossible option.

As a result it is inevitable that radar systems will be developed to detect stealth aircraft. I'm sure they already exist and more are certainly on the drawing board and coming soon.

[Robert A Cook PE]

One way is to use a very high power emitter that slightly changes frequencies constantly.
Then pepper your expected approach rout with (multiple mobile or fixed) receivers. The signal is reflected away from the target but not towards the emitter receiver. Instead, any other receivers each get a tiny part of the signal. Use the outside separate receivers to build uo a path over time.

[PapaBear3625]

If you can locate a stealth plane to within a cubic mile, that means you can vector planes to them, even if you can't get missile lock. And the closer you get, the less stealthy the target is.

A missile with its own active radar that gets close enough, would likely acquire a stealth aircraft.