James A Cross

US Patent:

43522076, Sep 28, 1982

Filed:

Apr 18, 1980

Appl. No.:

6/141603

Inventors:

James A. Cross - Azusa CA
John E. Snyder - Diamond Bar CA

Assignee:

R.F. Technical Products, Inc. - Diamond Bar CA

International Classification:

H04B 110

US Classification:

455223

Abstract:

A noise-suppressing circuit suitable for insertion between a receiving antenna and an RF receiver to suppress noise in the RF signal received by the receiving antenna includes a bandpass filter circuit connected to receive as an input the RF signal received by the antenna, and connected in series to a blanking circuit which employs a JFET to remove from the filtered RF signal the unwanted noise spikes. The bandpass filter attenuates the components of the RF signal that have frequencies outside of the passband, and after the blanking circuit has removed the noise spikes, it passes the remainder of the filtered RF signal to the RF receiver. In a preferred embodiment, the bandpass filter circuit includes a parallel resonant circuit, and the blanking circuit includes a series resonant circuit connected between the drain and the gate of JFET of the blanking circuit.