Antenna On Empire State Building

Fig. 6 A detailed view of the upper portion of the Empire Land Building showing locations of transmitting antennas.

1967 Facilities

Today the Empire Slate Building occupies a unique position in the circulate manufacture. It furnishes leased vertical space of 317 feet for the antennas of 22 stations. Between the 80th and 85th floors arc housed 35 separate broadcast transmitters with a combined total RF output power of over 400 KW. The Empire land Building Co. owns the master FM antenna and leases it to individual FM stations � perhaps the just such state of affairs in the globe. The visitor also has responsibility for general maintenance of the TV lower.

The tower is provided with a code beacon, and at that place is obstruction lighting at 3 lower levels. The mooring-mast section of the building is illuminated by alluvion-lights. FCC rules with respect to belfry painting are waived in favor of tower lighting 24 hours per day.

Stations� currently¹� transmitting from the edifice are listed below in order of their position from the meridian of the tower (Fig. 6).

WNBC-TV (ch. 4): 25.7 KW visual,

5,xiii KW audible at 1445 ft.* WNBC-FM (97.one MHz): one.1 KW at

1445 ft. WNBC visual, audible, and FM signals are triplexed into a single 4-bay superturnstile antenna 56 ft in length.

WPIX (TV) (ch. 2): 100 KW visual, 20 KW aural at 1400 ft, using a zigzag antenna 23 ft in length. (Also auxiliary antenna at 1325 ft level.)

WABC-TV (ch. 7); 110 KW visual, II KW aural at 1380 ft. using a Z-type antenna 25 ft in length.

WNEW-FM (102.7 MHz): 4.1 KW horizontal, 4.1 KW vertical at 1360 ft, A special single-bay antenna is used. It consists of 4 horizontal dipoles on the tower faces, and four vertical dipoles on the corners. All dipoles are positioned� between the upper two trophy� of the WNEW-TV array.

WNEW-Boob tube (ch. v): 37.one KW visual, � 5,5 KW audible at 1330 ft, A v-bay antenna 56 ft in length is� employed. The upper two bays | are used equally an auxiliary antenna,� while the lower three bays are� used as the main antenna,

WPIX (TV): This station also has a

single set of dipoles at the 1325- ft level equally an auxiliary antenna.

(Main antenna at 1400 ft.)

WCBS-Tv (ch. 2); 42 KW visual,

eight.32 KW aural at 1300 ft. A v-bay antenna 65 ft in length is used. The upper three bays are for visual, and the lower two bays for audible transmission.

WNYC-TV (ch. 31); 890 KW visual, 89 KW aural at 1290 ft. A special antenna, utilizing vertical slots in a collinear traveling wave array 40 ft in length is in service. There are 24 slots, or bays, in each element.

WABC-FM (95.5 MHz); 1.5 KW at 1270 ft.,

WCBS-FM (101.i MHz): one.5 KW at 1270 ft,

WABC-FM and WCBS-FM are duplexed into a single-bay antenna consisting of iv horizontal dipoles mounted on the tower faces between the two lower bays of the WCBS-Tv assortment.

WABC-TV and WNBC-TV: These stations have auxiliary antennas at the 1250-ft level (the very top of the mooring mast).

WOR-FM : An auxiliary antenna is located just beneath the base of operations of the Telly belfry.

WOR-TV (ch. nine): 155 KW visual, 31 KW aural at 1240 ft. A special two-bay antenna 8 ft in length is in use. Each bay consists of 24 dipoles as spaced around the top of the mooring mast, approximately 35 ft in diameter.

Primary FM Antenna: Each of the two trophy consists of xvi dipoles equally spaced around the mooring mast above and beneath the 102nd-floor observation deck. Peak is 1220 ft. Stations now using the array:

WBAI (FM) (99.5 MHz): five.iv KW horizontal, three.eight KW vertical

WHOM-FM (92.3 MHz): 5.4 KW horizontal, three.8 KW vertical

WLIB-FM (107.5 MHz): ii,0 KW horizontal, 1.45 KW vertical

WNCN (FM) (104.iii MHz): 5.4 KW 3.five KW vertical

WNYC-FM (93.9 MHz); 5.3 KW horizontal, three.7 KW vertical

WOR-FM 98.vii MHz): v.iv KW horizontal, 3.8 KW vertical

WPIX-FM (101.nine MHz): v.4 KW horizontal. 3.8 KW vertical

WQXR-FM (96.three MHz): 5.iv KW horizontal. 3,8 KW vertical

WRFM (FM) (105.1 MHz): five.2 KW horizontal, iii.vii KW vertical

WNDT (Tv set) (ch. 13): 178 KW visual,, 34.7 KW aural at 1180 ft. A stacked 6-bay Yagi, 27.5 ft in length, is employed.

WNJU-Television receiver (ch. 47): 234 KW visual, 46.8 KW aural at 1180 ft. In use is a special 4-bay vertical-slot antenna 52 ft in length. The antenna consists of two sections which are mounted on the north and south faces of the mooring mast.

The Time to come

Some time agone, a feasibility written report was conducted by a consulting engineering firm for the Empire State Building Co. This written report showed that the mooring mast could agree several more than UHF antennas. Currently a CP is held past WTVE (ch. 41). licensed to Patterson, Northward. J., which proposes another antenna on the building. Some other FM station is considering using the master FM antenna. Also, WABC-FM, WCBS-FM. and WNDT programme to install new antennas during the summer of 1967.

The world'southward nearly unusual antenna site may not exist much longer. Recently, the Port of Nov. York Authority has been planning the construction of twin 1 10-story skyscrapers in Lower Manhattan. Contained studies by Alford Manufacturing Co, and Jansky and Bailey take shown that the proposed towers would cause ghosting to some viewers watching some of the Television set stations presently on the Empire State Edifice. Several solutions to the programme have been advanced, ane being to relocate antennas from Empire State to the new. taller structures (to be known as the Earth Trade Center).

Any the future of the Empire Land Edifice antenna site. it remains a monument to the ability of broadcast engineers and stations to cooperate for their mutual welfare and for the public benefit.

Acknowledgements

The author wishes to give thanks the various engineers of the stations, networks, and companies mentioned for their assistance in preparing this report. He is peculiarly grateful to Thomas J. Buzalski of NBC. John F. Garrety of the Empire State Building Co., Dr. Frank G, Kear of Kear and Kennedy, Harold H. Leach of Alford Manufacturing Co., and Robert M. Morris, formerly of ABC and NBC.

¹ Power is ERP and superlative above average terrain, in all cases.

August-. 1967