The application discloses receive first detection device includes: the rotor, be equipped with on the rotor and be used for the fixed installation clamp of receiving the head, strutting arrangement, the rotor through the pivot install in strutting arrangement is last, strutting arrangement can rotate, just strutting arrangement's center of rotation line with the center of rotation line of rotor is non -parallel. According to the configuration, the utility model provides a receive first detection device, it can realize detecting the received signal angle of receiving the head.