Abstract: A method and apparatus for sampling optical input signal is presented. The apparatus includes a split waveplate for spatially rotating polarization direction of a first portion (for example half, or 50 percent) of the input signal to a first rotated direction and spatially rotating polarization direction of a second portion (for example the other 50 percent) of the input signal to a second rotated direction orthogonal to the first rotated direction. The apparatus further includes a sum frequency generator, for example a PPLN crystal, aligned to the first rotated direction to sample the input signal. The rotation of the two halves of the input signal is achieved using a split half-waveplate.

Abstract: A nonpolarization-dependent method and apparatus for optical sampling of a user optical signal of a known frequency range (e.g., corresponding to 1550 nm wavelength) uses a probe signal in an unsplit form and applies a conversion {e.g., by sum frequency generation (SFG) }operation in a first stage to the probe signal and to a first polarization component of the user optical signal (e.g., ‘s’ component) to produce a first component of an output signal. In a second stage, a second polarization component of the user optical signal (e.g., ‘p’ component) is rotated by 90° to align with the first polarization component and then converted by mixing with the unsplit probe signal to produce a second component of an output signal. The first and second output component signals are both added and measured using a photomultiplier tube (PMT) or an avalanche diode.

Abstract: Repetitive sampling of a data signal is performed. A clock reference is generated. The clock reference has a known period relationship with the data signal. The clock reference and the data signal are simultaneously sampled. The sampled information from the clock reference is used to determine in what phase of the clock reference sampled values of the data signal occur.

Abstract: An insect repelling device including a mat portion having a recess formed within an upper surface thereof. An insect repellent is disposed within the recess.

Abstract: A two speed pulley assembly comprised of a sheave, a brake member, an output member, and a brake. The sheave receives a rotational input and also includes a series of carrier arms which cooperate to define a circle which is coaxially with the sheave. Rollers are rotatably supported on said carrier arms. A braking member is rotatably supported relative to said sheave and includes portions defining a first raceway in contact with the rollers. An output sleeve is also rotationally supported relative to the sheave. The output sleeve includes portions defining a second raceway in contact with the rollers. The brake inhibits rotation of the braking member when engaged while permitting rotation thereof when disengaged. Mounted between the sheave and the output sleeve is a one-way clutch bearing. The clutch bearing engages when rotation of the sheave attempts to or begins to overrun rotation of the sleeve.

Abstract: A variable speed drive device for mounting to a rotatable shaft and being driven by first and second belts. The device includes a first pulley of a first diameter and a second pulley of a second diameter, each engaging one of the belts. The first pulley mounts directly to the shaft via a mounting hub extending laterally therefrom. The second pulley is positioned radially outward of the hub and a bearing is located between the two. Also located between the two is a clutch mechanism that engages when the second pulley tries to rotates faster than the first pulley. In this manner, the first pulley drives the shaft at a first speed when the first pulley is rotating faster than the second pulley and the second pulley drives the shaft at a second speed when the second pulley is trying to rotate faster than the first pulley.

Abstract: A gate lifter for shifting a gate from a valve seat in a gate valve. The gate lifter is provided on the downstream, or low pressure side of a valve, and is a tubular structure that surrounds and is slidable relative to a tubular valve seat. Hydraulic or other pressurized fluid is adapted to be introduced between an end of the lifter and a flange carried by the valve seat to cause the parts to move in opposite directions, as a result of which the lifter operates by shifting the gate member away from the valve seat to avoid damage to the valve seat as the gate member is moved there across. The gate lifter includes a face that is adapted to engage with a corresponding face of the gate member, the gate lifter face preferably including a low friction coating, such as teflon, gearings or gearing type material.