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:
Oct. 09, 1984
Filed:
Mar. 15, 1982
Yukinari Fujiwara, Musashimurayama, JP;
Hitachi Denshi Kabushiki Kaisha, Tokyo, JP;
Abstract
A system for detecting an abnormal condition of a high frequency output signal in its power level, comprising: a variable gain power amplifier which receives a high frequency input signal and produces an amplified high frequency output signal; a negative feedback control loop connected to the power amplifier, for automatically setting the power level of the amplified high frequency output signal to a desired one of a plurality of predetermined power levels, the negative feedback control loop being so arranged as to produce a DC signal which is constant in its magnitude so far as the power level of the high frequency output signal is maintained at its set value whichever one is selected from the plurality of predetermined power levels, the gain of the power amplifier being controlled on the basis of the DC signal; and a comparator which compares the DC signal with a reference signal to judge as to whether the high frequency output signal is abnormal or not in its power level.