Abstract: A portable gas chromatographic detector includes two identical platinum coils mounted on identically aligned conducting posts. One coil is placed in an occluded chamber; the other coil is placed in an identical isolated chamber. Both coils have connection to legs of a bridge circuit and have substantially identical current flow passed along their length. Both chambers are preferably identically dimensioned and are large enough not to interfere with the field of the coils. The occluded chamber communicates through a short passageway with a passing classified gas stream from a chromatographic column. It has been found that the motion with respect to one coil is compensated with respect to the motion with the remaining coil so that the only differential in electrical resistance measured across the bridge circuit is that induced by the cooling property of helium on the heated coil in the occluded chamber. Cycling of the portable chromatograph includes a first short cycle.

Abstract: Apparatus for attaching a multiconductor cable to a housing, such as the backshell of a connector, is disclosed that has a seal member located in the opening in the tubular section of the housing through which the cable extends into the housing to seal the space between the cable and the walls of the opening. A clamp is attached to the cable adjacent to the end of the tubular section. Washers are located on each side of the clamp and held in engagement with the clamp and the housing by a gland nut so that any forces imposed on the cable outside the housing will be transmitted to the housing by the clamp, the washers, and the gland nut and not be imposed on the section of cable in engagement with the seal member.

Abstract: A waterproof housing assembly for a geophone is disclosed that includes a housing having an elongated cavity. A geophone is mounted in the bottom portion of the cavity. A two conductor takeout cable extends into the cavity that has a first section where the outer sheath and insulation are stripped from the two conductors part of the way back from the end. A second section of the cable adjacent the first has the outer sheath removed from the insulated conductors. A body of elastomeric material is located in the cavity. It has a first pair of spaced openings through which the uninsulated first section of the cable extends to be connected to the geophone, a second pair of spaced openings connected to the first pair in which the second section of the cable is located, and a single opening connected to the second pair in which a portion of the sheathed cable is located.

Abstract: A method of plating simultaneously a large number of non-flat metal parts of very thin, easily bent material is disclosed. The parts of this type such as geophone springs are placed in a plating barrel in loose condition, and the barrel is submerged at least halfway into the plating solution. After a short period of time, rotation of the barrel is begun and allowed to continue for awhile before the electroplating current is turned on. The tumbling action imported to the geophone springs, which causes them to move into and out of electrical contact with each other and with the cathodes in the barrel, extends the time required to plate these very thin members with the desired coating of metal, usually silver or gold, thereby decreasing the criticalness of the length of time the plating current is on, thereby increasing the uniformity of the coatings obtained and reducing the number of rejects.

Abstract: A geophone comprising an annular coil-mass and a permanent magnet assembly positioned inside the annular coil-mass with their longitudinal axes generally coinciding to place the coil-mass in the magnetic field of the permanent magnet assembly. Spring spiders support the coil-mass on the permanent magnet assembly for axial and rotational movement relative to the permanent magnet assembly along and around the longitudinal axis thereof. Contacts extend outside the housing of the geophone to connect the geophone into an electrical circuit. Two axially spaced, parallel, spring spiders or diaphragm springs electrically connect the outside contacts to the terminals of the coils of the coil-mass.

Abstract: A waterproof multiple wire electrical cable connecting device is disclosed. The device includes two connector assemblies with each assembly adapted to be connected to the end of a multiple wire electrical cable. Each connector assembly is of the same construction and includes both a male pin type connector and a female socket type connector so that any two connector assemblies can be connected together to connect electrically the conductors in the cables to which they are attached. The male and female connectors of each assembly are mounted in a face plate in side-by-side position to mate with male and female connectors in another assembly. Seal means are provided to seal the connectors of each connector assembly, when assembled with the connectors of another connector assembly, from the ambient environment.

Abstract: The connector disclosed includes a body having a groove in which an electrical cable can be positioned. Electrical contacts are positioned in the groove with each contact having a sharp end for penetrating the insulation of the cable and engaging the electrical conductors of the cable. A movable cable clamping member is pivotally attached to the body to move the cable against the contacts to cause the contacts to penetrate the cable insulation and make electrical contact with the conductors. A cam arm is pivotally mounted on the body to move the clamping member. The arm has a cam surface in engagement with the clamping member that forces the member to force the cable into electrical contact with the contacts carried by the base member. When the cam arm has so moved the movable member, it is in an "over-the-center" position, which locks the clamping member in position holding the cable against the contacts and in the groove on the body.