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:
Jan. 06, 1981
Filed:
Jun. 19, 1979
Burtron D Schertz, Kokomo, IN (US);
Frederick A Aldridge, Russiaville, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A local oscillator suitable for integrated circuit construction in a radio receiver maintains low level voltage oscillations across a tank circuit which may include a varactor diode. An emitter-coupled pair of transistors with a small switch-over voltage has the collector of the second transistor connected to the base of the first. Third and fourth matching transistors have emitters connected to the bases of the second and first transistors, respectively, and grounded collectors. The base of the third transistor is connected through a diode to ground; while the base of the fourth transistor is connected through a matching diode and the tank circuit to ground. A source of electric power having a voltage greater than two diode drops above ground is effective to supply current through resistors to the bases of the first and second transistors. The small switch-over voltage of the emitter coupled pair and the current reduction from emitter to base of the fourth transistor provide for small voltage swings across the tank circuit to minimize mistracking with the RF tuned circuits.