With radar, new and old don't necessarily mix. For decades, radar had analog signal processors. In recent years, the industry has switched to digital signal processing, which tends to enhance radar echoes and produce a more detailed picture. Unfortunately, analog radars are not compatible with displays designed for digital radars. If you upgrade your navigation display, you will most likely need to upgrade your radar antenna dome or scanner as well. However, older analog radar antennas that are operational are often in demand by boat owners looking for a replacement radar antenna and usually sell well on the Internet.