[jimf15e]

Your "jammer" didn't save you. If the only alert you received was Ka then your *detector* warned you. However, you also hit on the reason why those who think detectors won't help you in instant-on encounters are wrong. If your detector went off when you were abeam the LEO, then he was likely targeting someone else and your detector sensed the signal. There's no way he could get your speed abeam you - there's no range change to derive speed off of. You need closing or opening range to accurately measure velocity.