Abstract: A 3-way valve for controlling the flow between first and second ports and a common port. The 3-way valve comprising a valve body having an integral flow portion and a valve stem having first and second valve members. The valve stem is pressfit assembled into the flow portion of the valve body where at least one of the first valve member and the flow portion momentarily deforms. The valve stem operates between a first position where fluid is allowed to flow between the common port and the second port and a second position where fluid is allowed to flow between the common port and the first port.

Abstract: In one embodiment, a sight tube flowmeter is formed of a plurality of fluoropolymer components welded together to form a unitary flowmeter body. The components can comprise a PFA upright sight tube having two end portions, a flow conduit extending therethrough and two fitting portions that are uniquely welded onto each end of the sight tube, and a fluoropolymer float device movable to various positions within the flow conduit depending on the flow level of the fluid flowing therethrough. The float device can be of conventional design or for those flowmeter embodiments where low fluid flow rates are to be measured, an elongate float can be utilized. The floats and, in particular, a designated portion thereof, are visible through the sight tube to provide visual indication of the position, and thus the flow rate of fluid flowing through the flowmeter. In addition, alternative embodiments include the implementation of the unique sight tube and elongate float design in conventional flowmeters.

Abstract: A valve made principally of plastic has a creep compensating features providing consistent engagement between valve members and their respective valve seats, minimizing creep, and compensating for any creep that does occur. The features compensate for compression of internal valve components as well as extension of the valve body. In a manually operated three way valve embodiment of the invention, a trapped spring mechanism inserted between an actuator portion and the upper valve member provides the closure force for the upper valve member on the upper valve seat. The first valve member and second valve member connect through a extensible portion. Valves according to the invention are particularly suitable for quarter-turn three-way manual diaphragm valves and for applications in the semiconductor industry.

Abstract: A 3-way valve for controlling the flow between first and second ports and a common port. The 3-way valve comprising a valve body having an integral flow portion and a valve stem having first and second valve members. The valve stem is pressfit assembled into the flow portion of the valve body where at least one of the first valve member and the flow portion momentarily deforms. The valve stem operates between a first position where fluid is allowed to flow between the common port and the second port and a second position where fluid is allowed to flow between the common port and the first port.

Abstract: A wide bandwidth frequency discriminator circuit (200) employs a wide bandwidth limiting amplifier (202) to amplify the IF signal portion of a received RF signal. A frequency-to-voltage circuit 208 is provided having a bandwidth substantially greater than the bandwidth of the IF signal. This discriminator (200) operates to form a detection system capable of discriminating between desired and undesired components of the received RF signal even when said desired and undesired components are nearly identical in amplitude. This is due in part to the enhanced frequency response provided by the discriminator (200).

Abstract: The invention comprises a three-way diaphragm valve. The valve has a housing having three flow ducts each leading into an open interior chamber. The open interior chamber is divided into a central chamber, an upper chamber and a lower chamber. A first valve seat is positioned between the central chamber and the upper chamber. A second valve seat is positioned between the central chamber and the lower chamber. A central valve stem assembly is slidably mounted in the valve and has a first valve member and a second valve member positioned to alternately engage the first valve seat and second valve seat respectively, to direct flow from one passageway to another. A spring bears against the valve stem assembly to bias the relative position of the valve members and valve seats in a first predetermined position.

Abstract: A frequency-locked loop (100) employs a controllable oscillator (102) for generating an output signal having a frequency, optional sampler (104), coupled to oscillator (102), for sampling the frequency of the output signal, a divider (106), coupled to optional sampling circuit (104), for dividing the output signal frequency to generate a prescaled signal and a microprocessor (108), coupled between the divider 106 and oscillator (102), for comparing the prescaled signal to a reference signal and generating a control signal for correcting frequency shifts based upon the comparison. The control signal generated by microprocessor (108) is non-continuous. During that time when microprocessor (108) generates no control signals, power is removed from various frequency-locked loop circuitry.

Abstract: An intelligent communcations node is capable of dynamically selecting frequency and time slot assignments for communications with remote communication devices having different communication protocols including different available frequencies and time slots in a TDMA system. A frequency agile transmitter and receiver combined with an adaptable time slot selector enables communications with remote devices utilizing different protocols. The time and frequency management capabilities of the node makes greater spectral efficiencies possible.

Abstract: A displacement transducer comprises a charge coupled device having a plurality of light sensitive stages arranged in a line. An obturating member connected to a member whose displacement is to be transduced is disposed between the charge coupled device and a light source. As the obturating member is moved, it varies the amount of light received by the respective stages of the charge coupled device, so that the charge distribution in the charge coupled device is representative of the position of the obturating member and therefore of the member whose displacement is to be transduced.

Abstract: Apparatus for measuring the phase difference between two electrical signals Asin (wt+.theta.), Bsin (wt+.phi.), given a reference signal Vsin wt generated by the apparatus, comprises a phase lock loop for generating a clock frequency f = 360F where F is the frequency of the reference signal. This clock frequency f is then used to tune a 360 stage CCD transversal filter which is used to filter successively the two first-mentioned signals, whose phase difference is then measured by a zero intercept system. The clock frequency f is used to give phase difference in degrees.The phase lock loop comprises a 90-stage CCD to which the reference signal is applied. The output of the CCD is applied to one input of a phase sensitive detector whose other input is connected to receive the reference signal, and the control signal produced by the phase sensitive detector controls a voltage controlled oscillator whose output is applied to the clock input of the CCD.

Abstract: In a spectrum analyzer, the analogue signal to be analyzed is periodically sampled and digitized, and the digit samples are formed into R successive arrays each containing 2N successive samples and each overlapping the previous array by 50%. The forward Fourier transforms of each array are then successively formed, and an array of 2P complex points is formed from the result of each transform, where L-P/2 and L+P/2-1 are the points which represent the upper and lower limits of a Vernier band to be studied in detail and each array extends from points L-P to L+P-1 (i.e. each array is twice the width of the Vernier band, and the Vernier band is symmetrically disposed therein): additionally, each array for which L and R are odd is complemented. The arrays thus formed are then each multiplied by a window function (effectively equivalent to a band pass filter), and the result is subjected to the inverse Fourier transform to form respective further arrays of 2P points.

Abstract: The analogue storage circuit includes a charge transfer device such as a charge-coupled device (CCD) and a quantizing circuit. The charge transfer device is arranged to shift an analogue signal from its input to its output, the analogue signal being subject to a change in magnitude during such shifting.The quantizing circuit receives the analogue signal from the output of the charge transfer device and quantizes that signal at a respective one of several substantially discrete levels. The quantizing circuit is arranged to apply the quantized analogue signal to the input of the charge transfer device, whereby in operation the analogue signal is circulated round the loop defined by the charge transfer device and the quantizing circuit. The quantizing circuit is further arranged to quantize the analogue signal, upon each subsequent receipt thereof, at the same one of the discrete levels.