David L Farnsworth

US Patent:

56253486, Apr 29, 1997

Filed:

Aug 30, 1995

Appl. No.:

8/521612

Inventors:

David F. Farnsworth - Forest Grove OR
Larry A. Park - Manning OR

International Classification:

G08B 2100

US Classification:

340690

Abstract:

A method and apparatus for sensing one or more physical parameters, including acoustic waves having frequencies from approximately 0 Hz to 15 Hz, electromagnetic waves having frequencies from approximately 0 Hz through 35 Hz and seismic waves having frequencies from approximately 0 Hz through 15 Hz, and detecting precursor seismic activity indicated therein. Acoustic waves are sensed using an infrasonic transducer that produces an electrical signal representative of such waves. Electromagnetic waves are sensed using a suitable antenna, the antenna preferably comprising AC power lines. The antenna produces an electrical signal representative of such waves. Seismic waves are sensed using an accelerometer that produces an electrical signal representative of such waves. In one embodiment of the invention, the electrical signals are routed to a signal conditioning mechanism that converts the signals into detect signals suitable for detection of precursor seismic activity, the detect signals being, in turn, routed to a processing unit for detection of precursor seismic activity. In another embodiment, the electrical signal representative of the electromagnetic radiation is passed in parallel through a filter function to isolate one or more detect signals having predetermined bandwidths, and through a comparison function to produce a rejection signal that indicates the presence of noise.

US Patent:

57571775, May 26, 1998

Filed:

Apr 26, 1995

Appl. No.:

8/424407

Inventors:

David F. Farnsworth - Forest Grove OR

Assignee:

OTW LLC - Paradise Valley AZ

International Classification:

G01V 312
G01V 100
H04B 1100
H01Q 146

US Classification:

324 72

Abstract:

An infrasonic frequency resonant circuit and method for use thereof. An electric power distribution system is employed both as antenna for ISF signals and as a source of inductive reactance for a resonant circuit tuned to a band within the ISF spectrum. A capacitor is placed from the neutral conductor to the ground conductor at an ac power outlet in a structure to form a resonant circuit ordinarily tuned to a band within the ISF spectrum. An ISF spectrum analyzer is connected to the neutral and ground terminals of the resonant circuit to visualize ISF electromagnetic signals induced on the electric power distribution system in both the frequency domain and the time domain and so as to be more readily evaluated.