US2836819A - Ultra-high frequency television antenna - Google Patents

Description

J. ARVAY, JR 2,836,819

May 27, 1958 ULTRA-HIGH FREQUENCY TELEVISION ANTENNA Filed Aug. 2'7, 1954 l6 n n T19: i L 112! C /4 /9 I /Z Y INVENTOR. John A r'l/czg Jr.

United States Patent ULTRA-HIGH FREQUENCY TELEVISION ANTENNA John Arvay, J12, Plant City, F13.

Application August 27, 1954, Serial No. 452,612

3 Claims. '(Cl. 3431-802) This invention relates to antennas, and more particularly to an improved ultra-high frequency television antenna.

A main object of the invention is to provide a novel and improved antenna especially suitable for use in ultrahigh frequency television reception, said antenna being simple in construction, being easy to install, and being substantially nondirectional.

A further object of the invention is to provide an improved ultra-high frequency television antenna which is inexpensive to fabricate, which is rugged in construction, which has high sensitivity in all directions, and which is especially resistant to wind and adverse weather conditions.

A still further object of the invention is to provide an improved ultra-high frequency television antenna which is relatively compact in size, which involves only a few parts, which may be rapidly set up, and which will not short out in wet weather conditions.

A still further object of the invention is to provide an improved ultra-high frequency television antenna which has high gain and which is especially suitable for fringe reception.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure l is a front elevational view of an improved ultra-high frequency television antenna according to the present invention, shown schematically connected to the input circuit of a television receiver.

Figure 2 is a transverse vertical cross sectional view taken on line 22 of Figure 1.

Referring to the drawings, the improved television antenna is designated generally at 11.

Designated at 12 is a suitable vertical support, such as :a metal mast which may be grounded, and secured to the top end of the mast 12 is a collar member 13 provided with the oppositely projecting horizontal stud elements 14, 14 of insulating material. The collar 13 and oppositely projecting stud elements 14, 14 may be integrally formed of suitable insulating material, such as plastic material or the like, and the collar member may be secured to the mast by means of suitable fastening means, such as the bolts 15, 15, as shown.

Designated respectively at 16, 16 are a pair of opposed tubular metal di-pole elements which receive the end portions of the studs 14, as shown, and which are secured to said studs, by the transversely extending terminal bolts 17, 17. The di- pole elements 16, 16 are of equal length, and may be suitably dimensioned in accordance with the television frequencies to be received, for example, may be each approximately four inches in length. The dipole elements 16, 16 extend substantially horizontally as shown and extend in opposite directions.

Designated at 18, 13 are respective director coils which concentrically surround the outer end portions of the di- pole elements 16, 16, the coils 18, 18 being of suitable conductive material, such as metal tubing, and being integrally connected to a horizontal intermediate section 19 which is secured and electrically connected at its intermediate point to the mast 12 below the collar element 13, as by the transversely extending securing bolt 26?.

pThe horizontal intermediate section 19 is downwardly offset a short distance below the director coils 18, 18, whereby it is in capacitive relation to both dipole elements 16, 1n, the compacitances 55 being connected respectively in circuit with the inductances defined by'the coils '18, 18. Thus, the coils 18, 18 forming the inductive portions of the director assembly, may comprise two turns each, said turns having a diameter of approximately two and one-half inches, each coil 18 extending longitudinally for a distance of approximately two and one-half inches. Thus, the intermediate capacitive portion 19 of the director assembly has a length of approximately four and one-half inches. The horizontal intermediate portion 19 of the director assembly may be spaced downwardly from the di-poles 16 by a distance of approximately two and one-'half'inches,

The capacitances between the respective dipole elements 16 and the intermediate element 19, and the inductances defined by the coils 13 define respective tuned circuits which are substantially resonant in the ultra-high frequency range and thus provide a maximum signal voltage across the television receiver input circuit 22.

As shown, the outer portions of the di-poles 16 extend concentrically through the coils 18, namely, approximately the outer halves of the respective dipoles, and the inner halves of said di-poles extend parallel to the horizontal intermediate portion 19 of the director assembl, as shown.

As above stated, the director coils 18 have a diameter of the order of one-half the length of the respective dipoles 16, and the longitudinal length of the coils substantially of the same order as one-half the length of said di-poles.

As shown in Figure l, the terminal bolts 17, 17 are respectively connected by transmission line wires 21, 21, forming part of a conventional television transmission line, such as a three-hundred ohm twin lead transmission line, to the input terminals of the television receiver, such as to the respective terminals of the television receiver input circuit 22.

The antenna above described may be easily installed, and is suitable for the reception of television signals from various directions, since it is substantially non-directional.

As shown in Figure l, the director coils 13 are preferably wound in the same direction. Thus, since the director assembly 19 is grounded by the connection of the center of element 19 to the grounded mast 12, the respective director coils 18 set up two separate electrical fields which are opposite in polarity, with respect to the desired frequency, and enable the array to be resonated to said desired frequency with maximum gain.

While a specific embodiment of an improved ultrahigh frequency television antenna has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore it is intended that no limitations be placed on the invention except those defined by the scope of the appended claimsv What is claimed is:

1. An ultra-high frequency antenna comprisin a vertical support, a pair of opposed horizontal di-pole elements secured to said support and having respective tern1i nals at their inner end portions, a straight conductive rod secured to said vertical support adjacent and parallel to both said di-pole elements, and respective director coils supportingly secured on the end portions of said conductive rod surrounding the outer end portions of the respective di-pole elements, said straight rod member being in capacitive coupling relation to both of said dipole elements and the director coils being in inductive coupling relation to the outer end portions of the respective di-p0le elements, said straight rod member and director coils defining a resonant'array with respect to said dipole elements. Y

nals at their inner end portions, a horizontal conductive 7 rod secured at its intermediate portion to said vertical 7 support below and extending parallel to both of said di- 2. An ultra-high frequency antenna comprising a verti- 1 cal support, a pair of opposed horizontal di-pole elements secured to said support and having respective terminals at their inner end portions, a horizontal conductive rod secured at its intermediate portion to said vertical support below and extending parallel to both of said di-pole elements, and respective director coils integrally formed on the end portions of said conductive rod surrounding the outer portions of the respective di-pole elements, said outer portions of the di-pole elements extending axially through said director coils, said straight rod member fbeing in capacitive coupling relation to both of said dipole elements and the director coils being in inductive coupling relation to the outer end portions of the respective .dipole elements, said straight rod member and director coils defining a resonant arraywith respect to said dipole elements.

3. An ultra-high frequency antenna comprising a vertical support, a pair of opposed horizontal di-pole elements secured to said support and having respective termipole elements, and respective director coils integrally formed on the end portions of said conductive rod surrounding the outer portions of the respective di-pole elements, said outer portions of the di-pole elements extending axially through said director coils, said straight rod member being in capacitive coupling relation to both of said dipole elements and the director coils being in V di-pole elements.

References Cited in the file of this patent UNITED STATES PATENTS Grimditch July 15, 1941 Ferris et al. Jan. 24, '1950 Miller Ian. 29. 1952

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