US2471256A - Radio antenna - Google Patents

Description

V. M. WINTERMUTE May 24, 1949.

RADIO ANTENNA Filed May 22, 1948 Patented May 24, 1949 RADIO ANTENNA Vern M. Wintermute, North Plainfield, N. J.,. as-

signor to Lyte Parts Company, Plainfield, N. J a corporation of New Jersey Application May 22, 1948; Serial No. 28,712

1 Claim. 1

Thisinvention relates to improvements in antenna structures. It is particularly directed to an improved antenna for the reception of signals of frequencies associated with" television and frequency modulation broadcasting.

It is the primary object of the present invention to provide an antenna which will accommodate all of the presently designated television channels and frequency modulation bands.

A further object of my invention is to provide a directional dipole antenna arranged for the higher frequencies and lower frequencies in television broadcasting, with which is associated a novel and useful reflector assembly.

A still further object of my invention is to provide an antenna for television and frequency modulation signals which is complete with all necessary parts, which will give trouble-free service, and which is arranged for ready installation on a suitable antenna mast.

The antenna of the present invention is similar in some respects to that which is shown in an earlier application, Serial Number 20,618, for Television antenna, filed April 13, 1948; in which application I am a co-inventor with George E.

Zellinek, now abandoned.

In the drawings,

Figure 1 is a perspective view showing the antenna structure of my invention supported on an antenna mast, shown fragmentarily, and

Figure 2 is a cross-section view taken on the lines 2-2 of Figure 1.

Referring to the two views of the drawing, the antenna of my invention includes a pair of reversely folded tubular conducting metal dipole elements it, coplanar in part with respect to each other on an electrical insulating panel II, the latter of which is affixed by means of a flat bracket I2 to one end of a horizontal tubular cross-arm or stand-off tube I3. Cross-arm i3 is, in turn, pivotably fixed to the top end of a suitable antenna mast I4, as by the use of T bracket I5 located approximately midway of the length of the cross-arm. A reflector assembly designated generally at I6 is affixed to the end of the cross-arm I3 opposite to that of the dipole assembly.

The folded dipole loops Iil are engaged by and held in rolled edges of thin flat sheet metal mounting plates II for fastening with machine screws, to panel H, and they are of suitable combined length for optimum reception of signals in the lower frequency channels assigned to television and to frequency modulation in the frequency range between 44 and 108 megacycles.

Loops II] are, additionally, angularly bent and staggered whereby their free, inwardly directed, open ends cross each other infront. of panel- II to form, in efiect, a V type antenna for the reception of signals in the higher frequency television channels in the frequency range between 174 and 216 megacycles. Separation of the free open ends of loops I0 is maintained by the engagement therewith of suitable strips of insulating material l8.

Three parallel tubular multiple piece metallic reflector rods 20, 2D, and 20 constitute the principal elements of the rejector assembly I6, which rods are centrally secured to a bracket l2 fixed to the end of cross-arm I3. The rehector elements are co-planar and horizontally disposed corresponding in elevation with the dipole; and it will be noted that they are graduated in length with the longest rod 20 in the topmost position. Stability for the free ends of the reflector rods is maintained with insulating strips M which are drilled to fit over the rods and serve to tie them together and thus assist in preventing sagging and bending.

I prefer to make the folded dipole of a length which is approximately one-half wavelength at the geometric center of the lower frequency television band, and of suitable proportion so that I avoid any sharp peaks in a curve of signal response of my antenna compared with a tuned dipole. For the higher frequency channels, the combined length of the legs of the V corresponds approximately to one half wavelength at the geometric center of the band. The reflectors 20, 2B and 20 may each correspond in length to one half wavelength in a particular lower frequency channel, as for example in channels number 4, 5, and 6. Thus, as will be understood by those skilled in the art, I obtain maximum signal response over the range where it is most desired.

Transmission line lead-in wiring 25 of suitable characteristics is used, preferably comprising a co-axial cable and matching stub, with the shield of the co-axial cable terminating in the mounting plate I I for the dipole element on the left hand side and the hot wire of the co-axial cable crossing over for termination with the matching stub in the mounting plate I! for the right hand dipole element. An insulator 26 fastened to the depending end of bracket I2 and a second insulator 26' serve to position and insulate the cable and the matching stub as the wiring is directed downwardly from the antenna, and suitable provision is made immediately below insulator 26' to ground the shield of the co-axial cable and the matching stub to the antenna mast.

It will be appreciated by those who are skilled in the art that certain optional or necessary changes in the arrangement of parts and in their specifications may be substituted for those illustrated, depending upon the type and specifications of the receiving set with which my improved antenna is used. I do not, therefore, wish that the invention be limited to the specific apparatus other than as particularly pointed out in the subjoined claim.

Having thus described my invention in a preferred embodiment of the principles thereof, I claim:

In an antenna for the reception of television signals or the like, in combination, a pair of antenna elements; each element consisting of a linear conductor folded back on itself to provide a pair of parallel legs having a closed end and an open end and angularly formed so that the closed end with a substantial portion of the linear conductor lies in one plane While the open end and a substantial portion of the remainder of the conductor lies in an intersecting plane, the

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Carter Mar. 7, 1939 OTHER REFERENCES Tele-Tech for March 1947, pp. 58-62.

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