Abstract: A frequency source for providing a desired source frequency has a direct digital synthesis circuit having a DDS output including a desired DDS frequency, a plurality of low-level spur frequencies and a plurality of high-level spur frequencies; a first clock input for the direct digital synthesis circuit; a second clock input for the direct digital synthesis circuit; a DDS filter in communication with the DDS output; and a controller. The controller selects one of the clock inputs to avoid having a high-level spur in an output of the DDS filter. The source frequency is provided at the DDS filter output.

Abstract: A temperature stabilization scheme reduces the effects of temperature variations on the performance of an electronic system that is implemented on a circuit board. In the temperature stabilization scheme, the circuit has an isolated region that is coupled to a remainder ofthe circuit board by one or more electrical pathways. Associated with each of the electrical pathways is an incidental thermal conduction path between the isolated region and the remainder of the circuit board. A temperature sensitive component ofthe electrical system is coupled to a mounting site on the isolated region and interfaces with the remainder of the circuit board through the one or more electrical pathways. A series of heaters, thermally coupled to the isolated region provides a compensating thermal profile that opposes thermal instability caused by the incidental thermal conduction paths, where the opposition is over a portion of the isolated region that includes at least the mounting site of the temperature sensitive component.

Abstract: A method of installing a floatable pump apparatus and an anti-erosion plate at a selected location in a bounded water treatment basin wherein the floatable pump apparatus includes a float having a central opening therethrough and a motor and axial flow propeller-type pump. A winch is temporarily mounted on the upper side of the float and one end of the winch cable is extended downwardly through the central opening in the float and attached to the anti-erosion plate. The float and winch with the anti-erosion plate suspended from the winch cable is then lifted by a shore based crane and deposited in the water treatment basin adjacent the boundary of the basin. The float with the anti-erosion plate buoyantly supported thereby, is moved to the desired location in the basin and the winch then operated to lower the anti-erosion plate onto the bottom of the basin. The float is thereafter moved back to the boundary of the basin.