Abstract: A power regulating ballast for gaseous discharge lamps operated from a source of high-frequency power incorporates a method in an apparatus which utilizes a distributed capacitance in combination with an inductor and includes a current feedback derived from charges in the current flow through the lamp.

Abstract: A portable spa having a vertically rigid side wall, and a flexible inner including inflatable seat chambers which may be connected in series for filling with a fluid and inflatable backrest chambers which are partially filled with fluid and air.

Abstract: A high frequency system for gas discharge lamps includes a method of, and apparatus for, controlling the operation of a plurality of gas discharge lamps and provides; a reduction in starting and operating voltage and current; an increased range of dimming; and improved efficiency and reliability.

Abstract: A connector for tubes of square cross-section comprises an elongated hollow metallic member of such size and shape in external cross-section as to be insertable within an end length of a tube for connection therewith. The member has at least two external longitudinal surfaces of minor width on opposite sides thereof. Spaced integral transverse teeth are provided on at least one of the longitudinal surfaces, the transverse distance between the surface of the teeth and the opposite longitudinal surface being greater than an internal transverse dimension of a tube to be connected to the member. Relative rotation between a tube and a member inserted therein causes the teeth to bite into an internal surface of the tube and thus establish secure connection. The connector may have teeth on both opposite longitudinal surfaces of minor width, and there may be a second pair of toothed longitudinal surfaces of minor width in quadrature relation with the first pair.