The mid-1990s marked the development of smaller more efficient marine radars. While such marine radars are illegal if used in land-mobile situations, a number of chasers were quick to adopt them in an effort to have mobile radar. These radars have been found to interfere with research radars, such as the Doppler on Wheels (DOW) utilized in field projects. The first personal lightning detection and mapping devices also became available and the first online radar data was offered by private corporations or, at first with delays, with free services. A popular data vendor by the end of the 1990s was WeatherTAP.