Storm Watch / Tornado Radar
Storm Watch / Tornado Radar Customer Case On average, the United States experiences 100,000 thunderstorms each year, causing about 1,000 tornadoes. The customer is trying to determine what meteorological conditions enable a large rotating thunderstorm (a "supercell") to drop a dangerous tornado-funnel. By determining what conditions must exist for the formation of an especially fierce tornado, researchers hope to develop accurate predictions of when and where such a tornado may touch down, giving the people time to evacuate. The customer wants to study tornadoes and other severe-storm features with an X-Band polarimetric Doppler radar. This mobile cloud-profiling radar is [...]
Capacitance Sensors vs. Eddy Current Sensors Application Note
Capacitance Sensors vs. Eddy Current Sensors Application Note Capacitance sensors and Eddy current sensors are both used for non-contact measurements. Capacitive probes use electric fields to measure the distance from the sensor face to the surface of a target that is typically conductive and grounded. Eddy current probes use an alternating AC current to induce a magnetic field in a conductive target instead. In turn, the induced magnetic field produces a back magnetic field that is proportional to the gap between the probe face and the target. In a recent application note, MTI Instruments examines the differences between capacitance [...]
Atmospheric Remote Sensing
Atmospheric Remote Sensing Customer Case The customer requires a combination of hardware and software ("data system") to do live update sampling, processing, display, and archival of atmospheric measurements using an airborne Lidar system. This system, which continuously emits laser pulses, measures line-of-sight velocity and backscattered signals at a particular range from the aircraft. Real-time performance is necessary to observe the state of the atmosphere and to assess the performance of their instrument. Their requirement is similar to that of laser Doppler anemometry. The signal from the Lidar system will vary continuously with time and the signal waveform will be [...]
Nuclear Decay Experiment
Nuclear Decay Experiment Customer Case A customer wants to measure nuclear decay rates of various radioactive isotopes. With each nuclear decay, the isotope under study simultaneously emits a beta particle, which is a high-speed electron, and a gamma particle, which is a high-frequency photon of light. Beta particles are detected with an efficiency of over 90% by a proportional gas counter that surrounds the radioactive isotope. Surrounding only one quarter of the isotope, a sodium iodide scintillator crystal detects gamma particles with about 25% efficiency. When it impinges on the scintillator crystal, a gamma creates a flash of visible [...]
Electron Spin Resonance (ESR) Experiment
Electron Spin Resonance (ESR) Experiment Customer Case A customer has an Electronic Spin Resonance (ESR) experiment. ESR is based on the fact that the magnetic moment of an electron precesses in an applied magnetic field, not unlike a child's top in a gravitational field, at a well-defined frequency called the Larmor frequency. Electromagnetic radiation at the Larmor frequency, when impinging on such an electron, will be preferentially absorbed. This principle is identical to that employed in Nuclear Magnetic Resonance (NMR), where the atomic nucleus precesses. In NMR, Larmor frequencies are of order 100 MHz. Because the electron is 2000 [...]
Nuclear Ion Testing
Nuclear Ion Testing Customer Case This customer is involved in nuclear ion testing. The pulse amplitudes of nuclear ions from a detector must be measured and sorted into a histogram, which will show the number of times a given amplitude was received. The customer wants a "multi-channel analyzer" capable of analyzing 4,000 to 8,000 "channels." In the customer's terminology, "channels" are actually histogram bins. The customer has pulses coming in at 20 - 30 ms minimum interval and needs to peak detect (calculate the maximum value of the pulse). Then, based on peak height, each is stored in a [...]
White Paper: Hipot Testing of Military/Aerospace Interconnect Components
Introduction Operational performance and safety are paramount concerns when determining the acceptability of a range of interconnection products in military and aerospace applications. Connectors and relays, wires, wire bundled into cables and harnesses, all must be tested against stringent standards. The number and range of these standards is mind-numbing — and this paper makes no attempt to catalog them all. Rather, notable and salient MIL standards and similar aerospace standards will be used to site the key role that high-performance electrical safety testers, ancillary equipment and software play in effecting reliable and cost-effective compliance testing of components as [...]
Alpha Particle Counting
Alpha Particle Counting Customer Case A customer has to characterize a new design for a solid state alpha particle detector. The detector is essentially a silicon diode with a large area face. Because alpha particles, which are high-speed helium nuclei, are electrically charged, they interact strongly with matter and lose their energy quickly upon entering a solid. When an alpha particle decelerates within the depletion region of the diode, it creates electron-hole pairs. The carriers are collected by the diode's electrodes and create a measurable current pulse. The customer's experimental solid state detector has two implanted electrodes whose signals [...]
Laser Spectroscopy
Laser Spectroscopy Customer Case An academic researcher is studying the attenuation properties of different materials inside Laser cavities for applications in Laser Spectroscopy. The Laser pulses are generated by one Laser, and are then transmitted by mirrors into another cavity filled with gaseous material. In the second cavity, the light pulses are continuously reflected by opposite mirrors and their intensities are measured by a transducer which converts them into decaying pulses of 30 nanosecond width. The decay takes about 40 microseconds to settle. The researcher is required to capture the decaying pulses and save the captured data onto the [...]
Laser Transient Absorption Spectroscopy
Laser Transient Absorption Spectroscopy Customer Case The customer's setup is a scientific application in which transient signals from a Laser Absorption Spectroscope are transferred to a computer. The laser power is modified in steps and the process is repeated. The measurement sensitivity is limited by noise generated by the current digitizer. The customer wants to capture and continuously average very small pulse responses. The lowest signal pulse height is 0.5 milliVolts and can range up to 2 mV. The duration of each response pulse is 1 to 10 microseconds. The Pulse Repetition Frequency (PRF) is 10 Hz. The customer's [...]