Patent ID: 6275195
Filing Date: 2001-08-14
Classification: H01Q

Abstract:
A frequency adjustable antenna for transceivers operable at different radio frequencies comprising:m. a lower electrically conductive base mast section with a radio frequency connection thereto,n. an upper electrically conductive extensible mast section insulated electrically from said base mast section and adapted to hold in electrical contact therewith an elongated conductive whip,o. an elongated hollow cylindrical housing made of an electrically non-conductive material and having formed in an inner cylindrical wall surface thereof a longitudinally disposed helical groove,p. an electrically conductive loading coil comprised of a conductor formed into spaced convolutions comprising a helix of the same pitch as said helical groove in said housing, and fitting within said groove with an inner cylindrical surface of said helix located radially inward of said inner cylindrical wall surface of said housing,q. a contactor means carried by and electrically connected to said upper mast section for commutation with said spaced coil convolutions, said contactor means comprising a disk of electrically conductive material affixed to said upper electrically conductive mast section, said disk having protruding radially outwardly thereof a circumferential spring member comprised of a pair of axially spaced apart circumferential supporting band members having disposed axially therebetween a plurality of circumferentially spaced apart, adjacent arched tabs resiliently biased radially outwardly to contact a substantial sector of at least one coil convolution, andr. elevator means for raising and lowering said extensible mast section and said contactor means for selective commutation with said coil convolutions, thereby increasing and decreasing the tuned frequency length of the combined coil and two mast sections.