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BELL SYSTEM TECHNICAL JOURNAL 



The Whippany Station, 3XN 



A general view of the station site at Whippany is shown in Fig. 1. 

 The property consists of some 47 acres. The main laboratory building, 

 which is located near its center, is a two-story structure affording 

 approximately 18,000 square feet of floor space. The principal 

 antenna system involves two 250-foot steel towers with a suitable 

 buried ground system, which is placed some 500 feet out in front of 

 the building in order that the latter may be clear of the denser portion 



Fig. 2 — Operating room at 3XN. Transmitter for television channel on the 

 right. Power supply unit and radio transmitter for the speech channel in the 

 center and on the left, respectively. 



of the electric field. This antenna was assigned to the picture channel. 

 For the voice channel, a separate structure located 500 feet in the 

 rear of the laboratory building or approximately 1000 feet from the 

 other was employed. The original supports in this second case 

 were 60-foot wooden masts but subsequently metal topmasts were 

 added, bringing the total height to 100 feet. Both antennae were 

 energized by means of radio-frequency transmission lines. The 

 antenna tuning and coupling apparatus was housed in small buildings 

 placed under the center of each antenna, that for the larger structure 

 having a copper roof which was securely connected to the ground 

 network. 



This type of installation is thought to afford a number of advantages. 

 By separating the building and the antenna it becomes a much simpler 

 matter to control the electrical factors which enter into the design of 

 the latter. Removing the building from the field tends toward 



