Abstract: The output of a commercially available integrated high gain differential amplifier that already has reasonable linearity is connected back to the (?) input to obtain the well known circuit configuration for a non-inverting amplifier, whose gain may be unity or greater, and whose linearity in response to the (+) input is to be improved. We operate the part with power supplies that are dynamically varied to always be the amplifier input+N volts and that input?N volts. This allows the part to remain a low voltage swing part (±N volts) even though the actual output might swing several times that ±N volts. It improves linearity because the part is almost always operating at nearly ‘the same operating point’ relative to the perceived power supplies. The dynamically tracking power supplies maybe obtained from plus and minus higher voltage work supplies and the use of symmetrical current mirrors to produce matched ±N volt offsets that are referenced to the input of the amplifier.

Abstract: An electron impact ion source includes an ionization chamber in which a first rf multipole field can be generated and an ion guide positioned downstream from the ionization chamber in which a second rf multipole field can be generated wherein electrons are injected into the ionization chamber along the axis (on-axis) to ionize an analyte sample provided to the ionization chamber.

Abstract: The present disclosure provides an apparatus for handling a liquid sample, wherein the apparatus includes integrated sample processing and sample evaluating components. The sample processing and evaluating components can include solid matrices that allow for optical measurement of a sample, or for the removal of contaminants from a sample. Methods for using the apparatus to handle liquid samples and evaluate sample components are also provided.

Abstract: The present invention relates to an apparatus for delivering ions to a vacuum chamber. The apparatus comprises an ionization chamber, an ionization region within the ionization chamber, a vacuum interface at a vacuum interface voltage and a vacuum chamber, wherein the ionization chamber communicates with the vacuum chamber through the vacuum interface. Sample is introduced into the ionization chamber from an electrospray assembly at approximately ground potential. Two electrodes are provided within the chamber such that three electric fields are generated, a first field extending from the electrospray assembly to the first electrode, a second field extending from the second electrode to the first electrode, and a third field extending from the second electrode to the vacuum interface. Ions are forced to travel through the fields in order before entering the vacuum chamber. In addition, the invention provides a method of delivering ions to a vacuum chamber.

Abstract: An electronically controlled back pressure regulator comprises an analysis device having a vent coupled to the analysis device through a vent path, a pressure sensor coupled to the vent path, a proportional valve coupled to the vent path, the proportional valve configured to controllably alter pressure in the analysis device, and an electronically controlled closed-loop controller configured to control a flow through the vent based on a signal from the pressure sensor and an electronically controlled pressure setpoint.

Abstract: Methods and compositions for modifying a substrate surface are provided. In accordance with the subject methods, a substrate surface is contacted with a particulate-containing fluid. The fluid is then ultrasonically or sonically agitated to modify the substrate surface. In certain embodiments, the particulate-containing fluid has a pH above the isoelectric point of the substrate. Also provided are devices capable of providing ultrasonic and/or sonic energy and which include a non-acidic, particulate-containing fluid. The subject invention also provides systems and kits for use in practicing the subject methods.

Abstract: The apparatus measures timing variations, such as the jitter or wander in a timing signal (100) of a telecommunications network. A recovered clock signal is sampled and digitized to produce a series of digital clock samples which are then processed (135) with reference to a local digital reference signal to produce digital baseband frequency in-phase (I) and quadrature (Q) components (165, 170) these being further processed (145) to produce the digital phase information of said clock signal to determine (175) the required parameters of the network. The step of digitally processing said clock samples with reference to a local reference signal can be conveniently and cheaply implemented using a digital signal down-converter IC (135), for example of a type existing for digital radio receiver implementations. For jitter measurement, the local reference signal may be generated by a phase-locked loop (as in FIG. 2). For wander measurements an external reference clock is used (as in FIG. 3).

Abstract: A method of using at least a part of a cavity for a first and at least one second laser includes providing a first laser beam to the part of the cavity, splitting the first beam into a first and a second part, splitting the first part into a third and a fourth part, splitting the second part into a fifth and a sixth part, superimposing the third and the fifth part in a way causing extinguishing interference, superimposing the fourth and the sixth part in a way causing cumulative interference to provide a first resulting beam, and performing the above elements with at least one second laser beam provided to the same part of the cavity to provide a second resulting beam.

Abstract: A twisting fixture probe for cleaning oxides, residues or other contaminants from the surface of a solder bead probe and probing a solder bead probe on a printed circuit board during in-circuit testing.

Abstract: A description of signal behavior in the vicinity of a time and voltage of interest is produced by defining a region in the (time, voltage) plane that is a closed straight sided figure whose vertices are identified by threshold crossings offset for the voltage of interest and clocked by time delays offset from a clock time of interest. A first set of latches clocked by the time delays accumulates the state of signal behavior relative to the threshold voltages as it occurs, and their contents are subsequently transferred to a second set of latches at the start of a new clock cycle, allowing a new accumulation to begin and also allowing a detection logic circuit to operate on a unified and completed collection of indicators of what the just concluded description amounts to. The detection logic circuit responds to the combinations of latched indications to produce a signal corresponding to that description.

Abstract: An apparatus and method calculate a round-trip delay (RTD) between first and second endpoints within a network, where an intermediate point is selected between the first and second endpoints within the network. A network analyzer determines a first data transmission time from the intermediate point to the first endpoint and back to the intermediate point, determines a second data transmission time from the intermediate point to the second endpoint and back to the intermediate point, and adds the first and second data transmission times to determine therefrom the round trip delay between the first and second endpoints within the network.

Abstract: The invention provides an apparatus that produces analyte ions for detection by a detector. The apparatus includes a matrix based ion source having a target substrate including a carbon nanotube material for producing analyte ions, an ion transport system adjacent to the matrix based ion source for transporting analyte ions from the matrix based ion source; and an ion detector downstream from the ion transport system for detecting the analyte ions. The invention also provides a method for producing and detecting the analyte ions.

Abstract: A network analysis system and methods facilitate a match-corrected signal power measurement using a vector network analyzer (VNA). The network analysis system includes the VNA and a computer program stored in memory and executed by a controller. The computer program has instructions that implement one or both of calibrating a test port of the VNA to determine the match-corrected signal power measurement and correcting a power measured for a signal received at the test port of the VNA using corrected error terms of a port calibration of the test port to yield a corrected measured power. The corrected error terms are determined from error terms of the port calibration using a switch term and an incident power calibration, both of the test port. A method 100 determines the match-corrected signal power measurement and a method 300 calibrates the VNA test port to determine the measurement.

Abstract: An apparatus for packing a chromatography column with a granular packing medium is disclosed. The apparatus includes a chamber adapted to hold a mixture of the packing medium and a liquid. The chamber is in fluid communication with a pump and the column. A vibrator is positioned so as to agitate the mixture within the chamber. The invention also includes a method of packing the chromatography column by forming a mixture comprising the packing medium and the liquid, positioning the mixture within the chamber, agitating the mixture, and pumping liquid into the chamber thereby forcing the mixture through the column.

Abstract: Methods and devices for producing a polymer at a location of a substrate are provided. In the subject methods, a fluid droplet containing a first monomer labeled with a first detectable label is deposited from a fluid deposition device onto a location of a substrate surface having a second monomer labeled with a second detectable label. The first and second detectable labels are then detected to determine any misalignment between the fluid deposition device and the location of the substrate surface during deposition. Also provided are algorithms that perform the subject methods, as well as fluid deposition devices that include the subject algorithms. The subject invention also includes arrays produced according to the subject methods and kits that include the subject arrays.

Abstract: In one embodiment, a computer-implemented method 1) determines a current configuration of instruments which are connected in a user's test system; 2) retrieves an icon associated with each instrument (the icons being sized proportionally to the instruments they represent); 3) displays the icons within a GUI; and 4) graphically connects the icons within the GUI, in accord with the current configuration of instruments. In another embodiment, a computer-implemented method 1) determines a current configuration of instruments which are connected in a user's test system; 2) retrieves an icon associated with each instrument (the icons being pictures of the instruments); 3) displays the icons within a GUI; and 4) graphically connects the icons within the GUI, in accord with the current configuration of instruments. Other embodiments are also disclosed.

Abstract: A method and apparatus for maximizing the usage of a testhead of an in-circuit tester is presented. A testhead execution supervisor interfaces between a testhead controller and a graphical user interface used to enter manual tests. The testhead execution supervisor adds tests to be submitted to the testhead to one or more queues according to a priority scheme. Tests may be submitted to the testhead execution supervisor both as manual tests entered via the graphical user interface and as automatically generated tests generated by an automatic debug module. The automatic debug module may automatically generate tests for execution by the testhead that are executed when the testhead is idle, for example when no higher priority manual tests are scheduled.

Abstract: An interferometer is provided that minimizes the introduction of non-linear errors into displacement measurements. In one embodiment, non-linear errors are reduced by isolating reference and measurement beams over most of their respective optical paths leading to the detector, and by employing a separate amplitude-splitting non-polarizing optical beam splitter for each beam input into the interferometer. Additionally, the interferometer is scalable to an arbitrary number of optical axes or inputs.

Abstract: A distributed system with a timing signal path for increased precision in time synchronization among distributed system clocks. A distributed system according to the present teachings includes a master clock coupled to a timing signal path and a set of slave clocks coupled to the timing signal path. The master clock includes means for generating a timing signal on the timing signal path in response to time events associated with the master clock. The slave clocks include means for adjusting their local time in response to the timing signal received via the timing signal path.

Abstract: The present invention provides an apparatus and method for making an apparatus for sensing and/or characterizing a biopolymer translocating a nanopore. The apparatus of the present invention provides a first electrode, a first insulator, a second electrode, a optional insulator, a voltage source for applying a time varying potential difference between the electrodes, and a means of measuring the resulting current between the two electrodes. A method for making the apparatus is also disclosed.