It's biggest impact on post WW2 technology was (obviously) on radar technology. Technologies with broader application that were driven in part by radar research included electronics (driven by the development of smaller, lighter, more efficient, more robust radar systems, especially for aircraft radars (e.g., night fighters)), microwave technology (driven by the push towards shorter wavelengths), and analog computing (driven by the need for signal processing, and also automatic radar aiming of guns).

The impact on science (as opposed to technology) was important. Two major fields of physics were transformed from tiny fields with only a few pioneers working in them into major branches of physics: radio astronomy and ionospheric physics.

Both fields already existed, with pioneers such as Karl Jansky and Grote Reber working in radio astronomy, and Lloyd Berkner probing the ionosphere. After WW2, surplus radar dishes were turned into radio telescopes and ionosondes. This was not just a result of the technology having been developed, but also the result of unwanted (by the military) surplus hardware being readily available for re-purposing.

Radar technology was also important in meteorology, with weather radars using new techniques such as Doppler radar to provide unprecedented information about weather as it happened. Meteorology was perhaps the highest-impact scientific application of radar technology due to the importance of weather and its prediction, but not the only one: radar mapping, radar vegetation mapping, and radar observation and mapping of objects in our solar system.

The technologies with the biggest everyday impact on most people, not counting general improvement in electronics, are perhaps the microwave oven and improved weather forecasting, and the most cursed technology police radar for measurement of car speeds.

For an inside look at the transformation of radio astronomy, see R. Hanbury Brown, Boffin: A Personal Story of the Early Days of Radar, Radio Astronomy and Quantum Optics, Taylor and Francis, 1991.