Abstract: A tennis net tightening assembly adapted for installation as a unit inside the upper end of an existing tennis net post and which comprises an elongated threaded shaft journaled between a pair of support plates, one of which contacts a portion of the lower inner wall surface of the net post while the other support plate is fitted to the lower portion of a collar which is adapted to seat on the top of the net post and extends upwardly therefrom. A captured nut is located on the threaded shaft and includes a hook for engaging one end of the net support cable. The support cable passes through a slot in the upper portion of the collar, which additionally includes a semi-circular cable guide element adjacent the slot. The elongated threaded shaft is journaled between the support plates and includes a shank at its upper end which passes through the collar and is protected thereby.

Abstract: An underground watering system for an athletic facility such as a tennis court, comprising a plurality of select equally spaced shallow water reservoir trenches having rounded surfaces over which is applied a waterproof liner. A water distribution pipe is located on the lining at the bottom of such trench and extends the entire length thereof. The trenches are filled with fine stone aggregate over which is laid a water permeable fabric which covers the whole area to be watered. A relatively coarse layer of aggregate is placed over the fabric followed by an upper layer of relatively fine aggregate. A layer of playing surface material overlays the fine aggregate layer. Water supplied to the trenches via the distribution pipes will saturate the permeable fabric and will be drawn up to the playing surface by capillary action.