Dog crossbreed to by a type (not breed) name, such as Eurohounds (racing sled dogs) or Lurchers (hunting dogs). These dogs could be considered only as cross breeds, not as designer animals, since appearance is not the main reason for them to be bred. An exception to this is the Labradoodle, which although having a Portmanteau name, is often used as a Guide or Assistance dog as well as being popular family dogs. Although designer dogs are often selected by owners for their novelty, reputable breeders sometimes use crossbreeding in an attempt to reduce the incidence of certain hereditary problems found in
Low frequency can be received up to from the transmitting antenna. Low frequency waves can also occasionally travel long distances by reflecting from the ionosphere (the actual mechanism is one of refraction), although this method, called "skywave" or "skip" propagation, is not as common as at higher frequencies. Reflection occurs at the ionospheric E layer or F layers. Skywave signals can be detected at distances exceeding from the transmitting antenna. In Europe and Japan, many low-cost consumer devices have since the late 1980s contained radio clocks with an LF receiver for these signals. Since these frequencies propagate by ground wave only, the