US Patent 7511672 Antenna frequency modulating equipment

A frequency modulating equipment (20) for being used in an antenna (10) for modulating frequency of the antenna (10) to achieve a desired operating frequency, comprises a slide block (30) attached to a radiating element (11) of the antenna (10) and being capable of moving freely and a plastic element (21). The slide block (30) comprises a contact portion (300) contacting a free end of the radiating element (11) of the antenna (10). The plastic element (21) is fixed onto the antenna (10). The slide block (30) is installed on the plastic element (21). The antenna (10) can achieve a desired operating frequency by moving the modulating befittingly the slide block (30).