Abstract: A hunter safety system includes a plurality of highly visible signs that are deployed outward from a hunting spot. The signs include indicia which alerts others to the presence of a hunter to prevent them from shooting at the hunter and inform them of the location of the hunter. In this manner, others may position themselves on the backside of tree to avoid being inadvertently shot by the hunter who isn't aware of their location. The signs preferably include bright colors to contrast them from the foliage.

Abstract: A freezeless animal waterer has a vertical container having a top, bottom, sidewalls and an interior compartment. A vertical tube is located within the compartment and extends upwardly from the bottom to the top of the container with both the top and the bottom of the vertical tube being open. A pressurized water supply pipe extending from a riser tube in the ground extends through the vertical tube, and upwardly out of the upper end thereof, and thence downwardly back into the container and into the interior compartment, and terminates in an outlet opening. The cross sectional area of the pressurized water supply pipe is less than that of the vertical tube or the riser tube. An electrical heating element is positioned in the compartment to warm the water therein. At least one animal operable watering valve is located in the sidewall of the container to permit animals to selectively withdraw water from the compartment.

Abstract: A direction sensitive optical shaft encoder includes an optical shutter disk mounted to a shaft for rotation therewith, the optical shutter disk bearing at least first and second radially concentric tracks having alternating light transmissive and light blocking areas formed thereon. The light transmissive and light blocking areas of one track are angularly offset with respect to the light transmissive and light blocking areas of an adjacent track. A pair of light emitters and light detectors are disposed on opposite sides of the optical shutter disk and aligned with the first and second concentric tracks, respectively. Because the pattern of light transmissive and light blocking areas on the two tracks are angularly offset, the output of the light detectors follows a unique pattern which is dependent upon the direction of rotation of the optical shutter. The frequency of repetition of the pattern of outputs by the light detectors is indicative of the speed of rotation of the optical shutter.