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:
Feb. 03, 1981
Filed:
May. 07, 1979
Robert R Bell, Libertyville, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A frequency synthesizer for a citizens band transceiver is disclosed. The synthesizer utilizes a single master crystal oscillator whose output is coupled to a difference mixer that receives the output of a voltage controlled oscillator (VCO) and provides an input to a programmable frequency divider. This programmable divider provides an output to a phase-frequency comparator which commpares this signal to a reference signal supplied by a fixed divider coupled to the master crystal oscillator. The comparator output, through a low pass filter, controls the voltage controlled oscillator output. The VCO output signal is substantially higher than the maximum frequency capability of the programmable frequency divider, and the present invention by utilizing the master crystal oscillator and difference mixer provides an inexpensive frequency synthesizer utilizing a programmable frequency divider having relatively low maximum input frequency capabilities, and this accomplished without the use of costly multiplier circuits in the frequency synthesizer.