Abstract: High efficiency, low noise frequency tripler and method that generates an enhanced third harmonic of a frequency and suppresses the fundamental frequency component in the tripler output. The method comprises multiplying a constant plus a twice frequency component by a square wave at the fundamental frequency, such as by a modulator. The amplitude of the twice frequency component relative to the constant and the phase of the twice frequency component relative to the phase of the square wave are chosen to reduce the fundamental frequency component and enhance the third harmonic in the tripler output. An implementation using a differential Colpitts oscillator is disclosed.

Abstract: High efficiency, low noise frequency tripler and method that generates an enhanced third harmonic of a frequency and suppresses the fundamental frequency component in the tripler output. The method comprises multiplying a constant plus a twice frequency component by a square wave at the fundamental frequency, such as by a modulator. The amplitude of the twice frequency component relative to the constant and the phase of the twice frequency component relative to the phase of the square wave are chosen to reduce the fundamental frequency component and enhance the third harmonic in the tripler output. An implementation using a differential Colpitts oscillator is disclosed.

Abstract: An RF conductive shield can be fabricated from, and adhered to, a nonconductive substrate in the following manner. The RF conductive shield is fabricated in a predetermined geometric shape on the nonconductive substrate. Once the RF conductive shield is fabricated, it is cut from the nonconductive substrate to produce a separate RF shield. Having a separate RF shield, it can be placed on the nonconductive substrate in a predetermined location and adhered thereto.

Abstract: Optical filtering elements having two opposed surfaces and including at least one thin layer of stable non-reflective fluorescent material provide transparent articles which, when exposed to incident electromagnetic radiation at one surface of the fluorescent layer, absorb certain wavelengths within the fluorescent layer and emit other wavelengths at the opposed surface of the fluorescent layer. In preferred embodiments, when radiation (light) in the visible range (about 400 nm to about 700 nm) is incident on the element from one side, certain wavelengths of radiation which transverse the element are absorbed in the fluorescent layer and other radiation of greater, but also visible wavelengths are emitted from the opposed side without fluorescent light being reflected by the fluorescent layer at the incident side.

Abstract: Optical filtering elements having two opposed surfaces and including at least one thin layer of stable non-reflective fluorescent material provide transparent articles which, when exposed to incident electromagnetic radiation at one surface of the fluorescent layer, absorb certain wavelengths within the fluorescent layer and emit other wavelengths at the opposed surface of the fluorescent layer. In preferred embodiments, when radiation (light) in the visible range (about 400 nm to about 700 nm) is incident on the element from one side, certain wavelengths of radiation which transverse the element are absorbed in the fluorescent layer and other radiation of greater, but also visible wavelengths are emitted from the opposed side without fluorescent light being reflected by the fluorescent layer at the incident side.

Abstract: A conventional grain storage bin is equipped with means for ventilation and curing the stored grain by inducing air flow through the grain in response to a pressure differential existing between the interior of the bin and the outside atmosphere. The invention provides a break-away screen at the vent constructed to break away when the pressure differential exceeds a predetermined value, thereby preventing damage to the structure; e.g., collapse of the roof, walls, etc. when the pressure differential is created by a lower pressure inside the bin.