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:
Jul. 23, 1991
Filed:
Jun. 09, 1989
Applicant:
Inventor:
Leopold J Johnson, Valley Center, CA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
330 63 ; 455121 ; 455127 ;
Abstract
A magnetic amplifier switch is connected to a transmitter and antenna of a LF transmitting system. The transmitter is operable to produce a signal which is modulated to first and second frequencies, for example 'mark' and 'space' frequencies, at different times. The magnetic switch is connected with inductors which are also connected with the transmitter and antenna. Opening and closing of the magnetic amplifier switch changes the inductance of the antenna such that the antenna is automatically tuned to resonance at the one or the other of the modulated frequencies being transmitted at a given time.