GB1036158A - Improvements in aerials - Google Patents

Abstract

1,036,158. Aerials. NORTH WESTERN SPECIALITIES Ltd. Aug. 18, 1964 [May 20, 1963], No. 19901/63. Heading H4A. In an aerial assembly of a kind suitable for U.H.F. TV a boom 10, Fig. 1 (not shown), carries an active element F, directors D, and a slotted or perforated reflector plate R, the latter being so mounted that it may be folded down for transit (Fig. 2, not shown). As described, the boom 10 is made of square cross-section metal tubing, the directors are carried by insulators I secured to the boom by bolts 11 and the active element F is a folded dipole, stamped from metal in strip form with strengthening flanges f, which is bolted to the boom at the centre of its closed side, the ends of its open side being connected to one part of a junction box 12, the other part of which carries the feeder cable. The reflector plate R has two series s, s<SP>1</SP> of slots parallel to the aerial elements and separated by a portion of plate in which is another slot S, at right-angles to them, through which the boom 10 passes. A channel-shaped bracket 14 containing a channel-section insert is fastened to the reflector plate R and is pivoted to the boom by a pin P, its ends being formed so as to clip around the boom and hold the reflector when in its operating position at right-angles thereto. In another embodiment (Fig. 3, not shown) two aerial assemblies of this kind are stacked, insulating blocks being used to secure the open ends of each folded dipole, which are connected by two metal tubes carrying a central cable junction-box. Instead of the bracket 14 being formed with clips to grip the boom 10 it may be held in position by a hook bolt which passes through holes in the boom. The active element may be of other than folded dipole form, e.g. a " bow-tie " or " batswing." The insulators I may be omitted, and the directors and the active element may be arranged to fold against the boom 10 for transit.