The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 21, 1999
Filed:
Feb. 18, 1997
Norris M Clubb, Asheville, NC (US);
Tandy Corporation, Fort Worth, TX (US);
Abstract
A tunable capacitive coupling to a monopole antenna is provided which integrates the tuning mechanism into the supporting structure for the antenna. The base of the antenna is insulated from and supported by a cylindrical clamping assembly such as a metal compression ferrule in cooperation with an adjustment collar. This clamping mechanism enables the ferrule to be tightened like a drill bit in a chuck at any position along the base of the antenna. The coupling capacitance formed between the antenna radiator and the compression ferrule is proportional to the insertion depth of the antenna into the compression ferrule, thereby enabling the antenna to be tuned. The coupling method of the present invention enables repeatable tuning of the antenna either upward or downward in frequency within the band of frequencies accommodated by the particular antenna. The invention works especially well with so-called fiberglass antennas but is adaptable to metal elements having a lumped inductance and suitable insulation around the end of the antenna supported in the clamping assembly.