John C Hudson, Age 43South Houston, TX

4405033, Sep 20, 1983

Jan 26, 1981

6/228432

Lloyd E. Elliott - Houston TX
John L. Hudson - Houston TX

Texaco Inc. - White Plains NY

G01V 138
G01V 114

181120

New methods are disclosed for detecting the instant of firing of a gas exhausting gun such as an air gun which reduce plating action on two closely spaced apart electrodes submerged underwater very close to the gas exhausting gun exhaust comprising the basic steps of passing a current through the two electrodes, and periodically reversing the current to the two electrodes responsive to a polarity reversing circuit means after (1) a predetermined period of time or (2) after each firing of the gas exhausting gun. Likewise new methods for forming and assembling a fail-safe gas exhausting gun firing detection circuit are set forth in detail.

4427091, Jan 24, 1984

Jan 26, 1981

6/228433

Lloyd E. Elliott - Houston TX
John L. Hudson - Houston TX

Texaco Inc. - White Plains NY

G01V 138
G01V 114

181120

A new circuit is added to the old electrical circuit including two electrodes underwater positioned very close to a gas exhausting gun gaseous exhaust such as an air gun, wherein the exhaust from the firing gas exhausting gun momentarily blows away the conductive sea water from one or both of the electrodes to produce a high voltage pulse due to the large increase in resistance in the circuit indicating the precise moment of firing of the gas exhausting gun. This new circuit added to the above circuit is a circuit polarity reversing circuit which includes particularly a positive current generator, a negative current generator, and a sea ground for forming a third electron source when any of the two electrodes becomes defective, thus forming a fail-safe system. Further, the resultant circuit changes polarity of the electrodes after each firing of the gas exhausting gun and periodically reverses the current to the electrodes for reduced plating action on the electrodes, for reduced cross coupling between other channels, and for providing a fail-safe system.

4243116, Jan 6, 1981

Jul 23, 1979

6/059792

Lloyd E. Elliott - Houston TX
John L. Hudson - Houston TX

Texaco Inc. - White Plains NY

G01V 138
G01V 114

181118

A new circuit is added to an electrical circuit including two electrodes underwater positioned very close to an air gun gaseous exhaust wherein the exhaust from the firing air gun momentarily blows away the conductive sea water from one or both of the electrodes to produce a high voltage pulse due to the large increase in resistance in the circuit indicating the precise moment of firing of the air gun free of any uncertainty and mechanical noise which normally affects conventional transducers. This new circuit added to the above circuit is a circuit polarity reversing circuit which includes particularly a positive current generator, a negative current generator, and a sea ground for forming a third electron source when any of the two electrodes becomes defective, thus forming a fail-safe system. Further, the resultant circuit changes polarity of the electrodes after each firing of the air gun and periodically reverses the current to the electrodes for reduced plating action on the electrodes and for reduced cross coupling between other channels.